Compare Claude Sonnet 4.6 and DeepSeek V4 Pro: Agentic Coding vs Reasoning Math
Claude Sonnet 4.6 vs DeepSeek V4 Pro: which should I use?
Claude Sonnet 4.6 delivers industry-standard agentic tool call reliability ($3.00/$15.00 per million tokens), while DeepSeek V4 Pro provides deep mathematical reasoning and 1M context at budget rates ($0.55/$2.19 per million tokens). Verified 2026-09-07.
Verified 2026-09-07
Where can you find price, speed, and task evidence for Claude Sonnet 4.6 and DeepSeek V4 Pro?
Which tasks fit Claude Sonnet 4.6 and DeepSeek V4 Pro?
Best-fit task signals from the published model strengths; this is not a substitute for a controlled benchmark.
| Fact | Claude Sonnet 4.6 | DeepSeek V4 Pro |
|---|---|---|
| Best fit | Enterprise workloads that need Opus-adjacent quality at Sonnet pricing. | Rigorous math, proofs, and hard algorithmic problems on a budget. |
| Reasoning mode | Available | Available |
What does a Coding Agent workload cost with Claude Sonnet 4.6 and DeepSeek V4 Pro?
Modeled for Coding Agent: 20,000 input + 2,000 output tokens per task, 1 turn. This is a workload model, not a provider quote.
| Fact | Claude Sonnet 4.6 | DeepSeek V4 Pro |
|---|---|---|
| Coding Agent / task | $0.09 (modeled) | $0.03 (modeled) (winner) |
| Input / output rate | $3.00 / $15.00 per M | $1.32 / $3.96 per M |
How fast are Claude Sonnet 4.6 and DeepSeek V4 Pro?
Only non-estimated benchmark results are shown as measured.
| Fact | Claude Sonnet 4.6 | DeepSeek V4 Pro |
|---|---|---|
| Measured throughput | 76 tokens/s (winner) | 68 tokens/s |
| Time to first token | 360 ms | 480 ms |
How compatible are Claude Sonnet 4.6 and DeepSeek V4 Pro with APIs?
Provider-level wire-format and SDK facts; model-specific parameter differences may still apply.
| Fact | Claude Sonnet 4.6 | DeepSeek V4 Pro |
|---|---|---|
| OpenAI SDK | Not drop-in | Usable |
| Request shape | Messages API — system prompt is a top-level field, not a message role, and max_tokens is required on every call. | OpenAI-compatible chat/completions; set model to a deepseek-* id and point base_url at api.deepseek.com. |
| Streaming | SSE (Anthropic content-block events) | SSE (OpenAI delta) |
What are the privacy and retention policies for Claude Sonnet 4.6 and DeepSeek V4 Pro?
Provider policy and residency facts from the verified provider registry. A missing retention policy is not treated as a guarantee.
| Fact | Claude Sonnet 4.6 | DeepSeek V4 Pro |
|---|---|---|
| Provider says API data trains models | No | Unavailable |
| Published retention period | Unavailable | Unavailable |
| Data residency | Unavailable | Unavailable |
How much effort does it take to migrate between Claude Sonnet 4.6 and DeepSeek V4 Pro?
Direction is from each displayed model to the other. Effort is derived from provider compatibility and published parameter maps.
| Fact | Claude Sonnet 4.6 | DeepSeek V4 Pro |
|---|---|---|
| Move Claude Sonnet 4.6 → DeepSeek V4 Pro | config; 3 breaking parameter differences | Target: DeepSeek V4 Pro |
| Move DeepSeek V4 Pro → Claude Sonnet 4.6 | Source: DeepSeek V4 Pro | code-change; 3 breaking parameter differences |
| Why | Keep the `openai` SDK; change `baseURL` and the API key. | Messages API — system prompt is a top-level field, not a message role, and max_tokens is required on every call. |
Batch 53 · exact pair cross-provider decision contributions. Surface verification: 2026-09-02. These three boards are server-rendered from frozen scenarios; assumptions and unavailable joins are not observations.
Exact pair boundary: requested models are claude-sonnet-4-6 and deepseek-v4-pro. Provider, pricing, task, and rate-limit pages remain fact owners.
Sonnet-to-V4 request/response portability compiler
Frozen Batch 53 scenario board. Formula / decision rule: portability = every required semantic mapped ∧ validation probe passes; dropped or unknown semantics block migration Boundary: Wire-shape similarity is not semantic parity; this module owns only exact Sonnet-to-V4 replacement.
| Frozen scenario / field ID | Joined fields and evidence | Output | State |
|---|---|---|---|
batch53-claude-sonnet-4-6-vs-deepseek-v4-pro-m1-r1system instruction | pair=claude-sonnet-4-6 vs deepseek-v4-pro; surfaces=Anthropic Messages@api.anthropic.com / DeepSeek API@api.deepseek.com; requested IDs=claude-sonnet-4-6,deepseek-v4-pro; effective IDs=claude-sonnet-4-6,deepseek-v4-pro; source=Anthropic Messages; target=DeepSeek API; hosts=api.anthropic.com/api.deepseek.com; field mapping=system→system; prompt hash=port-001 | Map only after both response and instruction semantics are probed. | CONDITIONAL — validation probe required |
batch53-claude-sonnet-4-6-vs-deepseek-v4-pro-m1-r2extended reasoning | pair=claude-sonnet-4-6 vs deepseek-v4-pro; surfaces=Anthropic Messages@api.anthropic.com / DeepSeek API@api.deepseek.com; requested IDs=claude-sonnet-4-6,deepseek-v4-pro; effective IDs=claude-sonnet-4-6,deepseek-v4-pro; source control=thinking; target control=thinking; reasoning usage fields=required; config hash=port-002; exact IDs pinned | Unavailable — control semantics and usage accounting are not joined | UNAVAILABLE — reasoning mapping unknown |
batch53-claude-sonnet-4-6-vs-deepseek-v4-pro-m1-r3strict JSON | pair=claude-sonnet-4-6 vs deepseek-v4-pro; surfaces=Anthropic Messages@api.anthropic.com / DeepSeek API@api.deepseek.com; requested IDs=claude-sonnet-4-6,deepseek-v4-pro; effective IDs=claude-sonnet-4-6,deepseek-v4-pro; source schema=structured; target schema=JSON; parser=source/target; result hash=port-003; validation=field checker | Require a target parser/field probe; HTTP success alone is insufficient. | CONDITIONAL — parser change required |
batch53-claude-sonnet-4-6-vs-deepseek-v4-pro-m1-r4parallel tools | pair=claude-sonnet-4-6 vs deepseek-v4-pro; surfaces=Anthropic Messages@api.anthropic.com / DeepSeek API@api.deepseek.com; requested IDs=claude-sonnet-4-6,deepseek-v4-pro; effective IDs=claude-sonnet-4-6,deepseek-v4-pro; tool IDs/order=required; source/target call schema; side_effects=contained; config hash=port-004 | Unavailable — parallel event ordering and result association are not evidenced | UNAVAILABLE — tool trace missing |
batch53-claude-sonnet-4-6-vs-deepseek-v4-pro-m1-r5image input | pair=claude-sonnet-4-6 vs deepseek-v4-pro; surfaces=Anthropic Messages@api.anthropic.com / DeepSeek API@api.deepseek.com; requested IDs=claude-sonnet-4-6,deepseek-v4-pro; effective IDs=claude-sonnet-4-6,deepseek-v4-pro; source modality=image; target modality=text; artifact hash=port-005; preprocessing owner=required; information_loss=unknown | Do not silently turn an image into text and call it native parity. | BLOCKED — preprocessing semantic loss |
batch53-claude-sonnet-4-6-vs-deepseek-v4-pro-m1-r6streamed tool-call fixtures | pair=claude-sonnet-4-6 vs deepseek-v4-pro; surfaces=Anthropic Messages@api.anthropic.com / DeepSeek API@api.deepseek.com; requested IDs=claude-sonnet-4-6,deepseek-v4-pro; effective IDs=claude-sonnet-4-6,deepseek-v4-pro; stream events, call/result IDs, stop/usage fields=required; prompt hash=port-006; response parser=changed | Unavailable — joined stream export and usage settlement are absent | UNAVAILABLE — stream probe missing |
Provenance: Batch 53 claude-sonnet-4-6-vs-deepseek-v4-pro; first-party source Anthropic Messages API; surface verification date 2026-09-02. Missing joins fail closed.
Host-qualified replacement prerequisite ledger
Frozen Batch 53 scenario board. Formula / decision rule: eligible = exact host/ID + region evidence + credential owner + required capability + lifecycle join; unknown => Unavailable Boundary: Capabilities do not transfer between direct, cloud, gateway, or private hosts without host-qualified evidence.
| Frozen scenario / field ID | Joined fields and evidence | Output | State |
|---|---|---|---|
batch53-claude-sonnet-4-6-vs-deepseek-v4-pro-m2-r1Anthropic direct | pair=claude-sonnet-4-6 vs deepseek-v4-pro; surfaces=Anthropic Messages@api.anthropic.com / DeepSeek API@api.deepseek.com; requested IDs=claude-sonnet-4-6,deepseek-v4-pro; effective IDs=claude-sonnet-4-6,deepseek-v4-pro; provider=Anthropic; host=api.anthropic.com; requested/effective=claude-sonnet-4-6; region=provider-documented; credential=Anthropic key | Baseline host is retained for fallback; target prerequisites are not inferred from it. | BASELINE — fallback retained |
batch53-claude-sonnet-4-6-vs-deepseek-v4-pro-m2-r2Bedrock | pair=claude-sonnet-4-6 vs deepseek-v4-pro; surfaces=Anthropic Messages@api.anthropic.com / DeepSeek API@api.deepseek.com; requested IDs=claude-sonnet-4-6,deepseek-v4-pro; effective IDs=claude-sonnet-4-6,deepseek-v4-pro; provider=Anthropic; host=Bedrock; exact Sonnet ID=required; region/residency=required; credential owner=AWS; tools/schema=probe | Unavailable — paired target host and residency evidence are not joined | UNAVAILABLE — cloud prerequisite gap |
batch53-claude-sonnet-4-6-vs-deepseek-v4-pro-m2-r3Vertex | pair=claude-sonnet-4-6 vs deepseek-v4-pro; surfaces=Anthropic Messages@api.anthropic.com / DeepSeek API@api.deepseek.com; requested IDs=claude-sonnet-4-6,deepseek-v4-pro; effective IDs=claude-sonnet-4-6,deepseek-v4-pro; provider=Anthropic; host=Vertex; exact Sonnet ID=required; region/residency=required; credential owner=Google; lifecycle=dated | Unavailable — Vertex lifecycle and exact response contract are absent | UNAVAILABLE — host lifecycle gap |
batch53-claude-sonnet-4-6-vs-deepseek-v4-pro-m2-r4DeepSeek direct | pair=claude-sonnet-4-6 vs deepseek-v4-pro; surfaces=Anthropic Messages@api.anthropic.com / DeepSeek API@api.deepseek.com; requested IDs=claude-sonnet-4-6,deepseek-v4-pro; effective IDs=claude-sonnet-4-6,deepseek-v4-pro; provider=DeepSeek; host=api.deepseek.com; requested/effective=deepseek-v4-pro; region=declared; credential=DeepSeek key; schema/tools=required | Direct V4 is eligible for probing only after exact model and request contract settle. | CONDITIONAL — target probe required |
batch53-claude-sonnet-4-6-vs-deepseek-v4-pro-m2-r5shared gateway | pair=claude-sonnet-4-6 vs deepseek-v4-pro; surfaces=Anthropic Messages@api.anthropic.com / DeepSeek API@api.deepseek.com; requested IDs=claude-sonnet-4-6,deepseek-v4-pro; effective IDs=claude-sonnet-4-6,deepseek-v4-pro; provider/host=gateway; requested=V4 alias; effective ID=unknown; region=unknown; credential owner=shared gateway | Do not call a gateway alias a replacement while effective identity is unknown. | BLOCKED — identity unresolved |
batch53-claude-sonnet-4-6-vs-deepseek-v4-pro-m2-r6private-deployment candidate | pair=claude-sonnet-4-6 vs deepseek-v4-pro; surfaces=Anthropic Messages@api.anthropic.com / DeepSeek API@api.deepseek.com; requested IDs=claude-sonnet-4-6,deepseek-v4-pro; effective IDs=claude-sonnet-4-6,deepseek-v4-pro; artifact/revision=required; tokenizer=required; region/residency=required; credential owner=private operator; lifecycle=required | Unavailable — deployment right, artifact, and lifecycle evidence are not joined | UNAVAILABLE — private path unproven |
Provenance: Batch 53 claude-sonnet-4-6-vs-deepseek-v4-pro; first-party source DeepSeek API documentation; surface verification date 2026-09-02. Missing joins fail closed.
Quality-floor and rollback release gate
Frozen Batch 53 scenario board. Formula / decision rule: promote = paired acceptance ≥ floor ∧ critical cohorts pass ∧ failure delta within bound; otherwise retain Sonnet fallback Boundary: Retry, reviewer, and rate inputs are assumptions unless observed for this exact pair, host, and workload.
| Frozen scenario / field ID | Joined fields and evidence | Output | State |
|---|---|---|---|
batch53-claude-sonnet-4-6-vs-deepseek-v4-pro-m3-r1supervised coding | pair=claude-sonnet-4-6 vs deepseek-v4-pro; surfaces=Anthropic Messages@api.anthropic.com / DeepSeek API@api.deepseek.com; requested IDs=claude-sonnet-4-6,deepseek-v4-pro; effective IDs=claude-sonnet-4-6,deepseek-v4-pro; cohort=code; prompt/config/result hashes=required; floor=tests+review; retry/reviewer=declared; rates=dated links | Unavailable — matched local cohort and failure delta are missing | HOLD — critical cohort untested |
batch53-claude-sonnet-4-6-vs-deepseek-v4-pro-m3-r2strict extraction | pair=claude-sonnet-4-6 vs deepseek-v4-pro; surfaces=Anthropic Messages@api.anthropic.com / DeepSeek API@api.deepseek.com; requested IDs=claude-sonnet-4-6,deepseek-v4-pro; effective IDs=claude-sonnet-4-6,deepseek-v4-pro; cohort=extract; schema hash=required; field agreement floor=declared; output usage=required; exact IDs pinned | Unavailable — paired schema acceptance denominator is absent | HOLD — acceptance join missing |
batch53-claude-sonnet-4-6-vs-deepseek-v4-pro-m3-r3long text analysis | pair=claude-sonnet-4-6 vs deepseek-v4-pro; surfaces=Anthropic Messages@api.anthropic.com / DeepSeek API@api.deepseek.com; requested IDs=claude-sonnet-4-6,deepseek-v4-pro; effective IDs=claude-sonnet-4-6,deepseek-v4-pro; cohort=long-text; context allocation=declared; citation rubric=required; cache isolation=required | Unavailable — usable-context and citation support are not joined | UNAVAILABLE — long-text evidence missing |
batch53-claude-sonnet-4-6-vs-deepseek-v4-pro-m3-r4tool agent | pair=claude-sonnet-4-6 vs deepseek-v4-pro; surfaces=Anthropic Messages@api.anthropic.com / DeepSeek API@api.deepseek.com; requested IDs=claude-sonnet-4-6,deepseek-v4-pro; effective IDs=claude-sonnet-4-6,deepseek-v4-pro; cohort=agent; tool/result IDs=required; side_effects=isolated; attempt_cap=2; rollback artifact=required | Unavailable — tool trace and rollback readiness are not observed | HOLD — agent gate |
batch53-claude-sonnet-4-6-vs-deepseek-v4-pro-m3-r5high-consequence reasoning | pair=claude-sonnet-4-6 vs deepseek-v4-pro; surfaces=Anthropic Messages@api.anthropic.com / DeepSeek API@api.deepseek.com; requested IDs=claude-sonnet-4-6,deepseek-v4-pro; effective IDs=claude-sonnet-4-6,deepseek-v4-pro; cohort=critical; expert reviewer=required; reasoning mode=exact; failure floor=declared; human approval=required | Keep Sonnet fallback and require human review; no automatic replacement. | BLOCKED — consequence floor |
batch53-claude-sonnet-4-6-vs-deepseek-v4-pro-m3-r6failed-canary fixture | pair=claude-sonnet-4-6 vs deepseek-v4-pro; surfaces=Anthropic Messages@api.anthropic.com / DeepSeek API@api.deepseek.com; requested IDs=claude-sonnet-4-6,deepseek-v4-pro; effective IDs=claude-sonnet-4-6,deepseek-v4-pro; candidate failure class=required; failure delta=measured; rollback target=claude-sonnet-4-6; side_effects=contained | Rollback to Sonnet immediately after a critical canary failure; rerun only with a new fixture hash. | ROLLBACK — fallback retained |
Provenance: Batch 53 claude-sonnet-4-6-vs-deepseek-v4-pro; first-party source DeepSeek API pricing; surface verification date 2026-09-02. Missing joins fail closed.
Method and limitations: every formula is deterministic and every assumption is labeled. Missing provider, host, alias, snapshot, version, effort, tool, modality, benchmark, workload, rate-period, timestamp, or result joins fail closed. Run the claude-sonnet-4-6-vs-deepseek-v4-pro Batch 53 scenario →
Batch 66 · exact-pair decision contributions · verified 2026-09-07
Exact pair boundary: Anthropic / DeepSeek; model endpoint, premier coding agent workhorse vs open-weights reasoning flagship, and pricing must join. Requested models are claude-sonnet-4-6 and deepseek-v4-pro. Provider, rate, pricing, and task pages remain fact owners.
Token pricing and 5.5x tariff multiple expenditure matrix
Frozen Batch 66 scenario board. Formula / deterministic rule: monthly_spend = calls * ((in_tokens * rate_in + out_tokens * rate_out) / 1M) Boundary: Owns base token tariff comparisons and workload expenditure modeling.
| Frozen scenario / field ID | Pair, identity, host, surface, and evidence fields | Result | State |
|---|---|---|---|
batch66-claude-sonnet-4-6-vs-deepseek-v4-pro-m1-r110K software engineering queries | pair=claude-sonnet-4-6 vs deepseek-v4-pro; provider=Anthropic / DeepSeek; hostA=api.anthropic.com; hostB=api.deepseek.com; surfaceA=Anthropic Messages API; surfaceB=DeepSeek API; requested/effective IDs=claude-sonnet-4-6,deepseek-v4-pro; scenario=10K software engineering queries; workload; prompt tokens; completion tokens; Sonnet 4.6 spend; DeepSeek V4 Pro spend; budget delta; cost winner; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — 10K software engineering queries is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
batch66-claude-sonnet-4-6-vs-deepseek-v4-pro-m1-r250K unit test generation passes | pair=claude-sonnet-4-6 vs deepseek-v4-pro; provider=Anthropic / DeepSeek; hostA=api.anthropic.com; hostB=api.deepseek.com; surfaceA=Anthropic Messages API; surfaceB=DeepSeek API; requested/effective IDs=claude-sonnet-4-6,deepseek-v4-pro; scenario=50K unit test generation passes; workload; prompt tokens; completion tokens; Sonnet 4.6 spend; DeepSeek V4 Pro spend; budget delta; cost winner; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — 50K unit test generation passes is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
batch66-claude-sonnet-4-6-vs-deepseek-v4-pro-m1-r3100K data extraction tasks | pair=claude-sonnet-4-6 vs deepseek-v4-pro; provider=Anthropic / DeepSeek; hostA=api.anthropic.com; hostB=api.deepseek.com; surfaceA=Anthropic Messages API; surfaceB=DeepSeek API; requested/effective IDs=claude-sonnet-4-6,deepseek-v4-pro; scenario=100K data extraction tasks; workload; prompt tokens; completion tokens; Sonnet 4.6 spend; DeepSeek V4 Pro spend; budget delta; cost winner; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — 100K data extraction tasks is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
batch66-claude-sonnet-4-6-vs-deepseek-v4-pro-m1-r4prompt caching active (Sonnet 90% read / DeepSeek off-peak) | pair=claude-sonnet-4-6 vs deepseek-v4-pro; provider=Anthropic / DeepSeek; hostA=api.anthropic.com; hostB=api.deepseek.com; surfaceA=Anthropic Messages API; surfaceB=DeepSeek API; requested/effective IDs=claude-sonnet-4-6,deepseek-v4-pro; scenario=prompt caching active (Sonnet 90% read / DeepSeek off-peak); workload; prompt tokens; completion tokens; Sonnet 4.6 spend; DeepSeek V4 Pro spend; budget delta; cost winner; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — prompt caching active (Sonnet 90% read / DeepSeek off-peak) is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
batch66-claude-sonnet-4-6-vs-deepseek-v4-pro-m1-r5batch processing active (50% both) | pair=claude-sonnet-4-6 vs deepseek-v4-pro; provider=Anthropic / DeepSeek; hostA=api.anthropic.com; hostB=api.deepseek.com; surfaceA=Anthropic Messages API; surfaceB=DeepSeek API; requested/effective IDs=claude-sonnet-4-6,deepseek-v4-pro; scenario=batch processing active (50% both); workload; prompt tokens; completion tokens; Sonnet 4.6 spend; DeepSeek V4 Pro spend; budget delta; cost winner; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — batch processing active (50% both) is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
batch66-claude-sonnet-4-6-vs-deepseek-v4-pro-m1-r6unresolved foreign currency conversion | pair=claude-sonnet-4-6 vs deepseek-v4-pro; provider=Anthropic / DeepSeek; hostA=api.anthropic.com; hostB=api.deepseek.com; surfaceA=Anthropic Messages API; surfaceB=DeepSeek API; requested/effective IDs=claude-sonnet-4-6,deepseek-v4-pro; scenario=unresolved foreign currency conversion; workload; prompt tokens; completion tokens; Sonnet 4.6 spend; DeepSeek V4 Pro spend; budget delta; cost winner; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — unresolved foreign currency conversion has no matched, dated bilateral observation. | FAIL CLOSED — manual, probe, or source evidence required |
First-party provenance: DeepSeek API pricing; verification date 2026-09-07. Missing or conflicting joins fail closed.
Context window saturation (200K vs 1M) capability gate
Frozen Batch 66 scenario board. Formula / deterministic rule: eligible = (context <= 200K ? Both : (context <= 1M ? DeepSeek : Excluded)) Boundary: Owns context scaling and capability gating for large repositories.
| Frozen scenario / field ID | Pair, identity, host, surface, and evidence fields | Result | State |
|---|---|---|---|
batch66-claude-sonnet-4-6-vs-deepseek-v4-pro-m2-r1small library codebase (30K tokens) | pair=claude-sonnet-4-6 vs deepseek-v4-pro; provider=Anthropic / DeepSeek; hostA=api.anthropic.com; hostB=api.deepseek.com; surfaceA=Anthropic Messages API; surfaceB=DeepSeek API; requested/effective IDs=claude-sonnet-4-6,deepseek-v4-pro; scenario=small library codebase (30K tokens); context size; Sonnet 4.6 eligible; DeepSeek eligible; Sonnet cost; DeepSeek cost; context gate verdict; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — small library codebase (30K tokens) is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
batch66-claude-sonnet-4-6-vs-deepseek-v4-pro-m2-r2application service module (120K tokens) | pair=claude-sonnet-4-6 vs deepseek-v4-pro; provider=Anthropic / DeepSeek; hostA=api.anthropic.com; hostB=api.deepseek.com; surfaceA=Anthropic Messages API; surfaceB=DeepSeek API; requested/effective IDs=claude-sonnet-4-6,deepseek-v4-pro; scenario=application service module (120K tokens); context size; Sonnet 4.6 eligible; DeepSeek eligible; Sonnet cost; DeepSeek cost; context gate verdict; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — application service module (120K tokens) is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
batch66-claude-sonnet-4-6-vs-deepseek-v4-pro-m2-r3large monolithic codebase (200K boundary) | pair=claude-sonnet-4-6 vs deepseek-v4-pro; provider=Anthropic / DeepSeek; hostA=api.anthropic.com; hostB=api.deepseek.com; surfaceA=Anthropic Messages API; surfaceB=DeepSeek API; requested/effective IDs=claude-sonnet-4-6,deepseek-v4-pro; scenario=large monolithic codebase (200K boundary); context size; Sonnet 4.6 eligible; DeepSeek eligible; Sonnet cost; DeepSeek cost; context gate verdict; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — large monolithic codebase (200K boundary) is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
batch66-claude-sonnet-4-6-vs-deepseek-v4-pro-m2-r4massive enterprise monorepo (600K tokens) | pair=claude-sonnet-4-6 vs deepseek-v4-pro; provider=Anthropic / DeepSeek; hostA=api.anthropic.com; hostB=api.deepseek.com; surfaceA=Anthropic Messages API; surfaceB=DeepSeek API; requested/effective IDs=claude-sonnet-4-6,deepseek-v4-pro; scenario=massive enterprise monorepo (600K tokens); context size; Sonnet 4.6 eligible; DeepSeek eligible; Sonnet cost; DeepSeek cost; context gate verdict; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — massive enterprise monorepo (600K tokens) is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
batch66-claude-sonnet-4-6-vs-deepseek-v4-pro-m2-r51M full context saturation test | pair=claude-sonnet-4-6 vs deepseek-v4-pro; provider=Anthropic / DeepSeek; hostA=api.anthropic.com; hostB=api.deepseek.com; surfaceA=Anthropic Messages API; surfaceB=DeepSeek API; requested/effective IDs=claude-sonnet-4-6,deepseek-v4-pro; scenario=1M full context saturation test; context size; Sonnet 4.6 eligible; DeepSeek eligible; Sonnet cost; DeepSeek cost; context gate verdict; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — 1M full context saturation test is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
batch66-claude-sonnet-4-6-vs-deepseek-v4-pro-m2-r6unsupported archive payload format | pair=claude-sonnet-4-6 vs deepseek-v4-pro; provider=Anthropic / DeepSeek; hostA=api.anthropic.com; hostB=api.deepseek.com; surfaceA=Anthropic Messages API; surfaceB=DeepSeek API; requested/effective IDs=claude-sonnet-4-6,deepseek-v4-pro; scenario=unsupported archive payload format; context size; Sonnet 4.6 eligible; DeepSeek eligible; Sonnet cost; DeepSeek cost; context gate verdict; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — unsupported archive payload format has no matched, dated bilateral observation. | FAIL CLOSED — manual, probe, or source evidence required |
First-party provenance: DeepSeek API documentation; verification date 2026-09-07. Missing or conflicting joins fail closed.
Agent tool call reliability versus mathematical reasoning accuracy
Frozen Batch 66 scenario board. Formula / deterministic rule: roi = value_delivered - tool_loop_spend; agent precision vs thinking mode depth Boundary: Owns task suitability and execution quality modeling.
| Frozen scenario / field ID | Pair, identity, host, surface, and evidence fields | Result | State |
|---|---|---|---|
batch66-claude-sonnet-4-6-vs-deepseek-v4-pro-m3-r1autonomous multi-file refactoring (Sonnet optimal) | pair=claude-sonnet-4-6 vs deepseek-v4-pro; provider=Anthropic / DeepSeek; hostA=api.anthropic.com; hostB=api.deepseek.com; surfaceA=Anthropic Messages API; surfaceB=DeepSeek API; requested/effective IDs=claude-sonnet-4-6,deepseek-v4-pro; scenario=autonomous multi-file refactoring (Sonnet optimal); domain workload; Sonnet 4.6 fit; DeepSeek V4 Pro fit; cost comparison; primary selection factor; architectural verdict; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — autonomous multi-file refactoring (Sonnet optimal) is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
batch66-claude-sonnet-4-6-vs-deepseek-v4-pro-m3-r2formal algorithmic proof (DeepSeek optimal) | pair=claude-sonnet-4-6 vs deepseek-v4-pro; provider=Anthropic / DeepSeek; hostA=api.anthropic.com; hostB=api.deepseek.com; surfaceA=Anthropic Messages API; surfaceB=DeepSeek API; requested/effective IDs=claude-sonnet-4-6,deepseek-v4-pro; scenario=formal algorithmic proof (DeepSeek optimal); domain workload; Sonnet 4.6 fit; DeepSeek V4 Pro fit; cost comparison; primary selection factor; architectural verdict; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — formal algorithmic proof (DeepSeek optimal) is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
batch66-claude-sonnet-4-6-vs-deepseek-v4-pro-m3-r3API integration tool loop execution | pair=claude-sonnet-4-6 vs deepseek-v4-pro; provider=Anthropic / DeepSeek; hostA=api.anthropic.com; hostB=api.deepseek.com; surfaceA=Anthropic Messages API; surfaceB=DeepSeek API; requested/effective IDs=claude-sonnet-4-6,deepseek-v4-pro; scenario=API integration tool loop execution; domain workload; Sonnet 4.6 fit; DeepSeek V4 Pro fit; cost comparison; primary selection factor; architectural verdict; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — API integration tool loop execution is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
batch66-claude-sonnet-4-6-vs-deepseek-v4-pro-m3-r4complex financial modeling calculation | pair=claude-sonnet-4-6 vs deepseek-v4-pro; provider=Anthropic / DeepSeek; hostA=api.anthropic.com; hostB=api.deepseek.com; surfaceA=Anthropic Messages API; surfaceB=DeepSeek API; requested/effective IDs=claude-sonnet-4-6,deepseek-v4-pro; scenario=complex financial modeling calculation; domain workload; Sonnet 4.6 fit; DeepSeek V4 Pro fit; cost comparison; primary selection factor; architectural verdict; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — complex financial modeling calculation is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
batch66-claude-sonnet-4-6-vs-deepseek-v4-pro-m3-r5agent loop runaway circuit breaker | pair=claude-sonnet-4-6 vs deepseek-v4-pro; provider=Anthropic / DeepSeek; hostA=api.anthropic.com; hostB=api.deepseek.com; surfaceA=Anthropic Messages API; surfaceB=DeepSeek API; requested/effective IDs=claude-sonnet-4-6,deepseek-v4-pro; scenario=agent loop runaway circuit breaker; domain workload; Sonnet 4.6 fit; DeepSeek V4 Pro fit; cost comparison; primary selection factor; architectural verdict; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — agent loop runaway circuit breaker is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
batch66-claude-sonnet-4-6-vs-deepseek-v4-pro-m3-r6unresolved evaluation metric | pair=claude-sonnet-4-6 vs deepseek-v4-pro; provider=Anthropic / DeepSeek; hostA=api.anthropic.com; hostB=api.deepseek.com; surfaceA=Anthropic Messages API; surfaceB=DeepSeek API; requested/effective IDs=claude-sonnet-4-6,deepseek-v4-pro; scenario=unresolved evaluation metric; domain workload; Sonnet 4.6 fit; DeepSeek V4 Pro fit; cost comparison; primary selection factor; architectural verdict; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — unresolved evaluation metric has no matched, dated bilateral observation. | FAIL CLOSED — manual, probe, or source evidence required |
First-party provenance: Anthropic Claude documentation; verification date 2026-09-07. Missing or conflicting joins fail closed.
Method and limitations: formulas are deterministic; observed and assumed inputs are labeled; no missing provider, host, account, region, realm, alias, snapshot, revision, weight, artifact, control, tool, modality, workload, rate-period, timestamp, or result is transferred. Run the claude-sonnet-4-6-vs-deepseek-v4-pro Batch 66 scenario →
How do Claude Sonnet 4.6 and DeepSeek V4 Pro compare on specs?
| Claude Sonnet 4.6 | DeepSeek V4 Pro | |
|---|---|---|
| Price (input) | $3.00/M | $1.32/M ✓ |
| Price (output) | $15.00/M | $3.96/M ✓ |
| Blended price | $6.00/M | $1.98/M ✓ |
| Context window | 300,000 tokens | 1,000,000 tokens ✓ |
| Max output | 64,000 tokens | 384,000 tokens ✓ |
| Modalities | text, vision | text |
| Reasoning mode | Yes | Yes |
| Released | 2026-03 | 2026-05 |
| Speed | 76 t/s ✓ | 68 t/s |
How much do Claude Sonnet 4.6 and DeepSeek V4 Pro cost at scale?
| Tokens / month | Claude Sonnet 4.6 | DeepSeek V4 Pro | Delta |
|---|---|---|---|
| 1,000,000 | $6.00 | $1.98 | $4.02 (3.0×) |
| 10,000,000 | $60.00 | $19.80 | $40.20 (3.0×) |
| 100,000,000 | $600.00 | $198.00 | $402.00 (3.0×) |
Choose Claude Sonnet 4.6 if…
- ✓Best intelligence-per-dollar in the Claude lineup
- ✓Fast enough for interactive coding agents
- ✓Reliable structured output
- ✓Enterprise workloads that need Opus-adjacent quality at Sonnet pricing.
Choose DeepSeek V4 Pro if…
- ✓Thinking mode with visible chain-of-thought
- ✓Frontier-level math and competition coding
- ✓Still far cheaper than closed frontier models
- ✓Rigorous math, proofs, and hard algorithmic problems on a budget.
Run this exact matchup right now
Send the same prompt to Claude Sonnet 4.6 and DeepSeek V4 Pro side by side and see the outputs yourself.
Try Claude Sonnet 4.6 vs DeepSeek V4 Pro FreeWhat are common questions about Claude Sonnet 4.6 and DeepSeek V4 Pro?
Is Claude Sonnet 4.6 cheaper than DeepSeek V4 Pro?
DeepSeek V4 Pro is cheaper, at $1.98 per million blended tokens vs $6.00 for Claude Sonnet 4.6.
Which has the bigger context window, Claude Sonnet 4.6 or DeepSeek V4 Pro?
DeepSeek V4 Pro has the larger context window: 1,000,000 tokens vs 300,000.
Can Claude Sonnet 4.6 replace DeepSeek V4 Pro for coding?
Both are viable for coding. Best intelligence-per-dollar in the Claude lineup (Claude Sonnet 4.6) vs Thinking mode with visible chain-of-thought (DeepSeek V4 Pro) — pick based on which strength matters more for your workload.
Which is faster, Claude Sonnet 4.6 or DeepSeek V4 Pro?
Claude Sonnet 4.6 is faster: 76 t/s vs 68 t/s, measured on our speed benchmarks.
Neither of these? See Claude Sonnet 4.6 alternatives or DeepSeek V4 Pro alternatives.
What related comparisons help choose between Claude Sonnet 4.6 and DeepSeek V4 Pro?
Claude Sonnet 4.6 pricingDeepSeek V4 Pro pricingvs Claude Sonnet 4.5vs Claude Sonnet 4vs Claude Opus 4.8vs Claude Sonnet 5Premium model tests
Pricing verified 2026-04-06. Specs verified 2026-08-14.