Compare GPT-5.6 Sol and Grok 4.3: Frontier Agentic Reasoning vs 1M High-Speed Inference
GPT-5.6 Sol vs Grok 4.3: which should I use?
GPT-5.6 Sol and Grok 4.3 both support 1M context windows. Sol delivers state-of-the-art general reasoning, complex agent planning, and 128K max output headroom; Grok 4.3 offers rapid token generation and real-time live data access. Verified 2026-09-07.
Verified 2026-09-07
Where can you find price, speed, and task evidence for GPT-5.6 Sol and Grok 4.3?
Which tasks fit GPT-5.6 Sol and Grok 4.3?
Best-fit task signals from the published model strengths; this is not a substitute for a controlled benchmark.
| Fact | GPT-5.6 Sol | Grok 4.3 |
|---|---|---|
| Best fit | Complex, multi-step professional and coding work where accuracy matters more than cost. | General-purpose work where speed and a huge context window both matter. |
| Reasoning mode | Available | Available |
What does a Coding Agent workload cost with GPT-5.6 Sol and Grok 4.3?
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 | GPT-5.6 Sol | Grok 4.3 |
|---|---|---|
| Coding Agent / task | $0.12 (modeled) | $0.03 (modeled) (winner) |
| Input / output rate | $4.00 / $20.00 per M | $1.25 / $2.50 per M |
How fast are GPT-5.6 Sol and Grok 4.3?
Only non-estimated benchmark results are shown as measured.
| Fact | GPT-5.6 Sol | Grok 4.3 |
|---|---|---|
| Measured throughput | 44 tokens/s | 98 tokens/s (winner) |
| Time to first token | 560 ms | 320 ms |
How compatible are GPT-5.6 Sol and Grok 4.3 with APIs?
Provider-level wire-format and SDK facts; model-specific parameter differences may still apply.
| Fact | GPT-5.6 Sol | Grok 4.3 |
|---|---|---|
| OpenAI SDK | Usable | Usable |
| Request shape | Canonical /chat/completions and /responses shape — every OpenAI-compatible provider on this site imitates it. | Full OpenAI chat/completions compatibility — point the openai SDK at api.x.ai and it works unmodified. |
| Streaming | SSE (OpenAI delta) | SSE (OpenAI delta) |
What are the privacy and retention policies for GPT-5.6 Sol and Grok 4.3?
Provider policy and residency facts from the verified provider registry. A missing retention policy is not treated as a guarantee.
| Fact | GPT-5.6 Sol | Grok 4.3 |
|---|---|---|
| Provider says API data trains models | No | Unavailable |
| Published retention period | Unavailable | Unavailable |
| Data residency | US by default; EU data residency available on enterprise agreements | Unavailable |
How much effort does it take to migrate between GPT-5.6 Sol and Grok 4.3?
Direction is from each displayed model to the other. Effort is derived from provider compatibility and published parameter maps.
| Fact | GPT-5.6 Sol | Grok 4.3 |
|---|---|---|
| Move GPT-5.6 Sol → Grok 4.3 | config; 0 breaking parameter differences | Target: Grok 4.3 |
| Move Grok 4.3 → GPT-5.6 Sol | Source: Grok 4.3 | config; 0 breaking parameter differences |
| Why | Keep the `openai` SDK; change `baseURL` and the API key. | Keep the `openai` SDK; change `baseURL` and the API key. |
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 gpt-5.6-sol and grok-4.3. Provider, pricing, task, and rate-limit pages remain fact owners.
Sol/Grok reasoning comparability compiler
Frozen Batch 53 scenario board. Formula / decision rule: comparable = same prompt/config/tools ∧ documented control mapping ∧ visible/hidden accounting joined; otherwise not comparable Boundary: Equal-looking controls do not imply equal compute; this module does not rank either provider broadly.
| Frozen scenario / field ID | Joined fields and evidence | Output | State |
|---|---|---|---|
batch53-gpt-5-6-sol-vs-grok-4-3-m1-r1default | pair=gpt-5.6-sol vs grok-4.3; surfaces=OpenAI Responses@api.openai.com / xAI API@api.x.ai; requested IDs=gpt-5.6-sol,grok-4.3; effective IDs=gpt-5.6-sol,grok-4.3; surface=OpenAI Responses/xAI API; controls=default; visible/hidden reasoning=source join; tools=none; prompt/config hash=reason-001 | Unavailable — default control semantics are not joined | UNAVAILABLE — default mapping missing |
batch53-gpt-5-6-sol-vs-grok-4-3-m1-r2low | pair=gpt-5.6-sol vs grok-4.3; surfaces=OpenAI Responses@api.openai.com / xAI API@api.x.ai; requested IDs=gpt-5.6-sol,grok-4.3; effective IDs=gpt-5.6-sol,grok-4.3; Sol effort=low; Grok control=low; exact IDs/hosts; tool policy=none; prompt/config hash=reason-002; source/date=first-party | Unavailable — cross-provider low control equivalence is not evidenced | NO MAPPING — labels differ |
batch53-gpt-5-6-sol-vs-grok-4-3-m1-r3medium | pair=gpt-5.6-sol vs grok-4.3; surfaces=OpenAI Responses@api.openai.com / xAI API@api.x.ai; requested IDs=gpt-5.6-sol,grok-4.3; effective IDs=gpt-5.6-sol,grok-4.3; Sol effort=medium; Grok control=medium; tools=declared; reasoning accounting=required; result hash=missing | Unavailable — paired result and reasoning-token fields are absent | UNAVAILABLE — evidence gap |
batch53-gpt-5-6-sol-vs-grok-4-3-m1-r4high | pair=gpt-5.6-sol vs grok-4.3; surfaces=OpenAI Responses@api.openai.com / xAI API@api.x.ai; requested IDs=gpt-5.6-sol,grok-4.3; effective IDs=gpt-5.6-sol,grok-4.3; Sol effort=high; Grok control=high; prompt/config hash=reason-004; schema=paired; acceptance rubric=required | Unavailable — matched acceptance and hidden-reasoning accounting are missing | UNAVAILABLE — acceptance gap |
batch53-gpt-5-6-sol-vs-grok-4-3-m1-r5max | pair=gpt-5.6-sol vs grok-4.3; surfaces=OpenAI Responses@api.openai.com / xAI API@api.x.ai; requested IDs=gpt-5.6-sol,grok-4.3; effective IDs=gpt-5.6-sol,grok-4.3; Sol control=max; Grok control=max; exact host/ID=required; visible/hidden accounting=required; tools=paired | Retain as separate provider settings until a documented mapping exists. | NOT COMPARABLE — mapping unknown |
batch53-gpt-5-6-sol-vs-grok-4-3-m1-r6unsupported cross-label fixtures | pair=gpt-5.6-sol vs grok-4.3; surfaces=OpenAI Responses@api.openai.com / xAI API@api.x.ai; requested IDs=gpt-5.6-sol,grok-4.3; effective IDs=gpt-5.6-sol,grok-4.3; Sol control=xhigh/ultra; Grok control=unsupported; requested/effective IDs=exact; config hash=reason-006 | Do not coerce unsupported labels into a numeric effort scale. | UNSUPPORTED — no cross-label join |
Provenance: Batch 53 gpt-5-6-sol-vs-grok-4-3; first-party source OpenAI model documentation; surface verification date 2026-09-02. Missing joins fail closed.
Fresh-answer provenance and support receipt
Frozen Batch 53 scenario board. Formula / decision rule: pass = claim/source coverage ≥ declared floor ∧ retrieval/query timestamps meet freshness SLA; missing metadata => Unavailable Boundary: API evidence is separate from consumer-app search behavior and broad live-data claims.
| Frozen scenario / field ID | Joined fields and evidence | Output | State |
|---|---|---|---|
batch53-gpt-5-6-sol-vs-grok-4-3-m2-r1timeless fact | pair=gpt-5.6-sol vs grok-4.3; surfaces=OpenAI Responses@api.openai.com / xAI API@api.x.ai; requested IDs=gpt-5.6-sol,grok-4.3; effective IDs=gpt-5.6-sol,grok-4.3; retrieval=none; source IDs=required; claim map=required; query timestamp=not applicable; prompt hash=source-001 | A timeless answer is eligible only under a no-retrieval rubric and exact result check. | CONDITIONAL — support check required |
batch53-gpt-5-6-sol-vs-grok-4-3-m2-r2dated news | pair=gpt-5.6-sol vs grok-4.3; surfaces=OpenAI Responses@api.openai.com / xAI API@api.x.ai; requested IDs=gpt-5.6-sol,grok-4.3; effective IDs=gpt-5.6-sol,grok-4.3; retrieval owner=declared; query/source timestamps=required; freshness SLA=declared; citations=required; hash=source-002 | Unavailable — paired dated-source traces are absent | UNAVAILABLE — freshness evidence missing |
batch53-gpt-5-6-sol-vs-grok-4-3-m2-r3cited research | pair=gpt-5.6-sol vs grok-4.3; surfaces=OpenAI Responses@api.openai.com / xAI API@api.x.ai; requested IDs=gpt-5.6-sol,grok-4.3; effective IDs=gpt-5.6-sol,grok-4.3; corpus/query hash=required; source IDs=required; claim-to-source coverage=required; reviewer=required | Unavailable — same corpus, trace, and reviewer denominator are not joined | UNAVAILABLE — research provenance gap |
batch53-gpt-5-6-sol-vs-grok-4-3-m2-r4live-market question | pair=gpt-5.6-sol vs grok-4.3; surfaces=OpenAI Responses@api.openai.com / xAI API@api.x.ai; requested IDs=gpt-5.6-sol,grok-4.3; effective IDs=gpt-5.6-sol,grok-4.3; retrieval timestamp=required; market data owner=required; citation fields=required; consumer-app/API separation=explicit | Do not transfer a consumer app’s live-data behavior to either undocumented API route. | BLOCKED — API provenance required |
batch53-gpt-5-6-sol-vs-grok-4-3-m2-r5conflicting sources | pair=gpt-5.6-sol vs grok-4.3; surfaces=OpenAI Responses@api.openai.com / xAI API@api.x.ai; requested IDs=gpt-5.6-sol,grok-4.3; effective IDs=gpt-5.6-sol,grok-4.3; source IDs=two or more; conflict map=required; adjudication rubric=required; result hash=source-005 | Require an explicit conflict outcome or human review; no unsupported winner. | CONDITIONAL — adjudication required |
batch53-gpt-5-6-sol-vs-grok-4-3-m2-r6no-citation fixtures | pair=gpt-5.6-sol vs grok-4.3; surfaces=OpenAI Responses@api.openai.com / xAI API@api.x.ai; requested IDs=gpt-5.6-sol,grok-4.3; effective IDs=gpt-5.6-sol,grok-4.3; answer hash=present; source IDs=none; freshness SLA=declared; claim support=zero | Fail a citation-required workload; do not infer provider quality from fluent text. | FAIL — unsupported claims |
Provenance: Batch 53 gpt-5-6-sol-vs-grok-4-3; first-party source xAI API documentation; surface verification date 2026-09-02. Missing joins fail closed.
Consequence-floor bilateral router
Frozen Batch 53 scenario board. Formula / decision rule: eligible = required evidence dimensions pass ∧ consequence floor met; disagreement or critical action => human review Boundary: This router is pair-specific and does not create a broad coding, research, or security winner.
| Frozen scenario / field ID | Joined fields and evidence | Output | State |
|---|---|---|---|
batch53-gpt-5-6-sol-vs-grok-4-3-m3-r1casual draft | pair=gpt-5.6-sol vs grok-4.3; surfaces=OpenAI Responses@api.openai.com / xAI API@api.x.ai; requested IDs=gpt-5.6-sol,grok-4.3; effective IDs=gpt-5.6-sol,grok-4.3; consequence=low; evidence=factuality/style; review=spot-check; Sol/Grok coverage=declared; attempt_cap=1 | Lower-consequence route may be selected after local acceptance check Measurement state: labeled assumption only. | ASSUMPTION — workload observation required |
batch53-gpt-5-6-sol-vs-grok-4-3-m3-r2production code | pair=gpt-5.6-sol vs grok-4.3; surfaces=OpenAI Responses@api.openai.com / xAI API@api.x.ai; requested IDs=gpt-5.6-sol,grok-4.3; effective IDs=gpt-5.6-sol,grok-4.3; consequence=medium; evidence=tests+review+tool trace; exact IDs=paired; attempt_cap=2; costs=dated links | Unavailable — paired code acceptance and cost joins are missing | UNAVAILABLE — evidence floor missing |
batch53-gpt-5-6-sol-vs-grok-4-3-m3-r3financial extraction | pair=gpt-5.6-sol vs grok-4.3; surfaces=OpenAI Responses@api.openai.com / xAI API@api.x.ai; requested IDs=gpt-5.6-sol,grok-4.3; effective IDs=gpt-5.6-sol,grok-4.3; consequence=high; evidence=field agreement+source spans; reviewer=expert; schema hash=required | Keep human review mandatory until both exact routes clear the evidence floor. | BLOCKED — expert floor |
batch53-gpt-5-6-sol-vs-grok-4-3-m3-r4security review | pair=gpt-5.6-sol vs grok-4.3; surfaces=OpenAI Responses@api.openai.com / xAI API@api.x.ai; requested IDs=gpt-5.6-sol,grok-4.3; effective IDs=gpt-5.6-sol,grok-4.3; consequence=high; evidence=recall+false-positive denominator; prompt/config hash=required; tool policy=none | Unavailable — paired security denominator is absent | NO SUPPORTED VERDICT — denominator missing |
batch53-gpt-5-6-sol-vs-grok-4-3-m3-r5public research brief | pair=gpt-5.6-sol vs grok-4.3; surfaces=OpenAI Responses@api.openai.com / xAI API@api.x.ai; requested IDs=gpt-5.6-sol,grok-4.3; effective IDs=gpt-5.6-sol,grok-4.3; consequence=high; evidence=dated citations+support coverage; freshness SLA=required; reviewer=required | Unavailable — fresh paired provenance and review are missing | HOLD — provenance floor |
batch53-gpt-5-6-sol-vs-grok-4-3-m3-r6irreversible-tool action | pair=gpt-5.6-sol vs grok-4.3; surfaces=OpenAI Responses@api.openai.com / xAI API@api.x.ai; requested IDs=gpt-5.6-sol,grok-4.3; effective IDs=gpt-5.6-sol,grok-4.3; consequence=critical; tool=write/delete; idempotency/rollback=required; human approval=required; attempt_cap=1 | Never auto-route a critical side effect; stop for human approval. | BLOCKED — side-effect gate |
Provenance: Batch 53 gpt-5-6-sol-vs-grok-4-3; first-party source OpenAI Responses API; 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 gpt-5-6-sol-vs-grok-4-3 Batch 53 scenario →
Batch 63 · exact-pair decision contributions · verified 2026-09-07
Exact pair boundary: OpenAI / xAI; model endpoint, equal 1M context, frontier agentic reasoning vs high-speed inference, and token pricing must join. Requested models are gpt-5.6-sol and grok-4.3. Provider, rate, pricing, and task pages remain fact owners.
Token pricing and promotional tariff transition ledger
Frozen Batch 63 scenario board. Formula / deterministic rule: spend_delta = sol_monthly_bill - grok_monthly_bill; Sol promo ends 2026-11-21 Boundary: Owns pricing differential modeling accounting for Sol promotional rates.
| Frozen scenario / field ID | Pair, identity, host, surface, and evidence fields | Result | State |
|---|---|---|---|
batch63-gpt-5-6-sol-vs-grok-4-3-m1-r110K queries under Sol promo rate ($4/$20) | pair=gpt-5.6-sol vs grok-4.3; provider=OpenAI / xAI; hostA=api.openai.com; hostB=api.x.ai; surfaceA=OpenAI Responses API; surfaceB=xAI API; requested/effective IDs=gpt-5.6-sol,grok-4.3; scenario=10K queries under Sol promo rate ($4/$20); monthly queries; Grok 4.3 spend; Sol promo spend; Sol standard spend; post-promo budget delta; economic verdict; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — 10K queries under Sol promo rate ($4/$20) is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
batch63-gpt-5-6-sol-vs-grok-4-3-m1-r250K queries under Sol standard rate ($5/$30) | pair=gpt-5.6-sol vs grok-4.3; provider=OpenAI / xAI; hostA=api.openai.com; hostB=api.x.ai; surfaceA=OpenAI Responses API; surfaceB=xAI API; requested/effective IDs=gpt-5.6-sol,grok-4.3; scenario=50K queries under Sol standard rate ($5/$30); monthly queries; Grok 4.3 spend; Sol promo spend; Sol standard spend; post-promo budget delta; economic verdict; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — 50K queries under Sol standard rate ($5/$30) is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
batch63-gpt-5-6-sol-vs-grok-4-3-m1-r3100K high-volume production queries | pair=gpt-5.6-sol vs grok-4.3; provider=OpenAI / xAI; hostA=api.openai.com; hostB=api.x.ai; surfaceA=OpenAI Responses API; surfaceB=xAI API; requested/effective IDs=gpt-5.6-sol,grok-4.3; scenario=100K high-volume production queries; monthly queries; Grok 4.3 spend; Sol promo spend; Sol standard spend; post-promo budget delta; economic verdict; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — 100K high-volume production queries is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
batch63-gpt-5-6-sol-vs-grok-4-3-m1-r4prompt caching active (50% both) | pair=gpt-5.6-sol vs grok-4.3; provider=OpenAI / xAI; hostA=api.openai.com; hostB=api.x.ai; surfaceA=OpenAI Responses API; surfaceB=xAI API; requested/effective IDs=gpt-5.6-sol,grok-4.3; scenario=prompt caching active (50% both); monthly queries; Grok 4.3 spend; Sol promo spend; Sol standard spend; post-promo budget delta; economic verdict; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — prompt caching active (50% both) is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
batch63-gpt-5-6-sol-vs-grok-4-3-m1-r5batch queue active (50% both) | pair=gpt-5.6-sol vs grok-4.3; provider=OpenAI / xAI; hostA=api.openai.com; hostB=api.x.ai; surfaceA=OpenAI Responses API; surfaceB=xAI API; requested/effective IDs=gpt-5.6-sol,grok-4.3; scenario=batch queue active (50% both); monthly queries; Grok 4.3 spend; Sol promo spend; Sol standard spend; post-promo budget delta; economic verdict; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — batch queue active (50% both) is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
batch63-gpt-5-6-sol-vs-grok-4-3-m1-r6unresolved billing currency | pair=gpt-5.6-sol vs grok-4.3; provider=OpenAI / xAI; hostA=api.openai.com; hostB=api.x.ai; surfaceA=OpenAI Responses API; surfaceB=xAI API; requested/effective IDs=gpt-5.6-sol,grok-4.3; scenario=unresolved billing currency; monthly queries; Grok 4.3 spend; Sol promo spend; Sol standard spend; post-promo budget delta; economic verdict; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — unresolved billing currency has no matched, dated bilateral observation. | FAIL CLOSED — manual, probe, or source evidence required |
First-party provenance: OpenAI API pricing; verification date 2026-09-07. Missing or conflicting joins fail closed.
Sequential execution throughput and streaming latency board
Frozen Batch 63 scenario board. Formula / deterministic rule: elapsed_time = ttft + (output_tokens / tps); Grok high throughput vs Sol deep reasoning Boundary: Owns response turnaround time and throughput modeling.
| Frozen scenario / field ID | Pair, identity, host, surface, and evidence fields | Result | State |
|---|---|---|---|
batch63-gpt-5-6-sol-vs-grok-4-3-m2-r1interactive short query (500 tokens) | pair=gpt-5.6-sol vs grok-4.3; provider=OpenAI / xAI; hostA=api.openai.com; hostB=api.x.ai; surfaceA=OpenAI Responses API; surfaceB=xAI API; requested/effective IDs=gpt-5.6-sol,grok-4.3; scenario=interactive short query (500 tokens); output tokens; Sol elapsed time; Grok 4.3 elapsed time; throughput ratio; responsiveness verdict; speed winner; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — interactive short query (500 tokens) is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
batch63-gpt-5-6-sol-vs-grok-4-3-m2-r2deep analytical response (4K tokens) | pair=gpt-5.6-sol vs grok-4.3; provider=OpenAI / xAI; hostA=api.openai.com; hostB=api.x.ai; surfaceA=OpenAI Responses API; surfaceB=xAI API; requested/effective IDs=gpt-5.6-sol,grok-4.3; scenario=deep analytical response (4K tokens); output tokens; Sol elapsed time; Grok 4.3 elapsed time; throughput ratio; responsiveness verdict; speed winner; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — deep analytical response (4K tokens) is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
batch63-gpt-5-6-sol-vs-grok-4-3-m2-r3extensive code generation (16K tokens) | pair=gpt-5.6-sol vs grok-4.3; provider=OpenAI / xAI; hostA=api.openai.com; hostB=api.x.ai; surfaceA=OpenAI Responses API; surfaceB=xAI API; requested/effective IDs=gpt-5.6-sol,grok-4.3; scenario=extensive code generation (16K tokens); output tokens; Sol elapsed time; Grok 4.3 elapsed time; throughput ratio; responsiveness verdict; speed winner; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — extensive code generation (16K tokens) is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
batch63-gpt-5-6-sol-vs-grok-4-3-m2-r4batch classification loop (50 calls) | pair=gpt-5.6-sol vs grok-4.3; provider=OpenAI / xAI; hostA=api.openai.com; hostB=api.x.ai; surfaceA=OpenAI Responses API; surfaceB=xAI API; requested/effective IDs=gpt-5.6-sol,grok-4.3; scenario=batch classification loop (50 calls); output tokens; Sol elapsed time; Grok 4.3 elapsed time; throughput ratio; responsiveness verdict; speed winner; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — batch classification loop (50 calls) is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
batch63-gpt-5-6-sol-vs-grok-4-3-m2-r5concurrency saturation latency test | pair=gpt-5.6-sol vs grok-4.3; provider=OpenAI / xAI; hostA=api.openai.com; hostB=api.x.ai; surfaceA=OpenAI Responses API; surfaceB=xAI API; requested/effective IDs=gpt-5.6-sol,grok-4.3; scenario=concurrency saturation latency test; output tokens; Sol elapsed time; Grok 4.3 elapsed time; throughput ratio; responsiveness verdict; speed winner; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — concurrency saturation latency test is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
batch63-gpt-5-6-sol-vs-grok-4-3-m2-r6unmeasured speed fixture | pair=gpt-5.6-sol vs grok-4.3; provider=OpenAI / xAI; hostA=api.openai.com; hostB=api.x.ai; surfaceA=OpenAI Responses API; surfaceB=xAI API; requested/effective IDs=gpt-5.6-sol,grok-4.3; scenario=unmeasured speed fixture; output tokens; Sol elapsed time; Grok 4.3 elapsed time; throughput ratio; responsiveness verdict; speed winner; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — unmeasured speed fixture is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
First-party provenance: All AI Ask measured speed dataset; verification date 2026-09-07. Missing or conflicting joins fail closed.
Autonomous software engineering quality break-even
Frozen Batch 63 scenario board. Formula / deterministic rule: break_even_accuracy = (sol_cost / grok_cost) - 1; defect loss saved justifies Sol spend Boundary: Owns accuracy-versus-cost trade-off modeling for complex engineering tasks.
| Frozen scenario / field ID | Pair, identity, host, surface, and evidence fields | Result | State |
|---|---|---|---|
batch63-gpt-5-6-sol-vs-grok-4-3-m3-r1zero defect cost (raw cost comparison) | pair=gpt-5.6-sol vs grok-4.3; provider=OpenAI / xAI; hostA=api.openai.com; hostB=api.x.ai; surfaceA=OpenAI Responses API; surfaceB=xAI API; requested/effective IDs=gpt-5.6-sol,grok-4.3; scenario=zero defect cost (raw cost comparison); scenario; Grok 4.3 monthly spend; Sol monthly spend; cost difference; break-even accuracy uplift; financial recommendation; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — zero defect cost (raw cost comparison) is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
batch63-gpt-5-6-sol-vs-grok-4-3-m3-r2low defect penalty ($10 per error) | pair=gpt-5.6-sol vs grok-4.3; provider=OpenAI / xAI; hostA=api.openai.com; hostB=api.x.ai; surfaceA=OpenAI Responses API; surfaceB=xAI API; requested/effective IDs=gpt-5.6-sol,grok-4.3; scenario=low defect penalty ($10 per error); scenario; Grok 4.3 monthly spend; Sol monthly spend; cost difference; break-even accuracy uplift; financial recommendation; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — low defect penalty ($10 per error) is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
batch63-gpt-5-6-sol-vs-grok-4-3-m3-r3medium defect penalty ($50 per error) | pair=gpt-5.6-sol vs grok-4.3; provider=OpenAI / xAI; hostA=api.openai.com; hostB=api.x.ai; surfaceA=OpenAI Responses API; surfaceB=xAI API; requested/effective IDs=gpt-5.6-sol,grok-4.3; scenario=medium defect penalty ($50 per error); scenario; Grok 4.3 monthly spend; Sol monthly spend; cost difference; break-even accuracy uplift; financial recommendation; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — medium defect penalty ($50 per error) is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
batch63-gpt-5-6-sol-vs-grok-4-3-m3-r4critical production bug ($200 per error) | pair=gpt-5.6-sol vs grok-4.3; provider=OpenAI / xAI; hostA=api.openai.com; hostB=api.x.ai; surfaceA=OpenAI Responses API; surfaceB=xAI API; requested/effective IDs=gpt-5.6-sol,grok-4.3; scenario=critical production bug ($200 per error); scenario; Grok 4.3 monthly spend; Sol monthly spend; cost difference; break-even accuracy uplift; financial recommendation; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — critical production bug ($200 per error) is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
batch63-gpt-5-6-sol-vs-grok-4-3-m3-r510% Grok retry scenario | pair=gpt-5.6-sol vs grok-4.3; provider=OpenAI / xAI; hostA=api.openai.com; hostB=api.x.ai; surfaceA=OpenAI Responses API; surfaceB=xAI API; requested/effective IDs=gpt-5.6-sol,grok-4.3; scenario=10% Grok retry scenario; scenario; Grok 4.3 monthly spend; Sol monthly spend; cost difference; break-even accuracy uplift; financial recommendation; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — 10% Grok retry scenario is a frozen fixture pending exact identity, configuration, and denominator joins. | UNTESTED — assumption cannot establish a verdict |
batch63-gpt-5-6-sol-vs-grok-4-3-m3-r6unresolved defect valuation | pair=gpt-5.6-sol vs grok-4.3; provider=OpenAI / xAI; hostA=api.openai.com; hostB=api.x.ai; surfaceA=OpenAI Responses API; surfaceB=xAI API; requested/effective IDs=gpt-5.6-sol,grok-4.3; scenario=unresolved defect valuation; scenario; Grok 4.3 monthly spend; Sol monthly spend; cost difference; break-even accuracy uplift; financial recommendation; prompt/config/input/output/result/cache/checkpoint/artifact hashes=required; evidence=2026-09-07; measurement versus assumption=explicit | Unavailable — unresolved defect valuation has no matched, dated bilateral observation. | FAIL CLOSED — manual, probe, or source evidence required |
First-party provenance: OpenAI model 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 gpt-5-6-sol-vs-grok-4-3 Batch 63 scenario →
How do GPT-5.6 Sol and Grok 4.3 compare on specs?
| GPT-5.6 Sol | Grok 4.3 | |
|---|---|---|
| Price (input) | $4.00/M | $1.25/M ✓ |
| Price (output) | $20.00/M | $2.50/M ✓ |
| Blended price | $8.00/M | $1.56/M ✓ |
| Context window | 1,000,000 tokens | 1,000,000 tokens |
| Max output | 128,000 tokens ✓ | 64,000 tokens |
| Modalities | text, vision | text, vision |
| Reasoning mode | Yes | Yes |
| Released | 2026-06 | 2026-06 |
| Speed | 44 t/s | 98 t/s ✓ |
How much do GPT-5.6 Sol and Grok 4.3 cost at scale?
| Tokens / month | GPT-5.6 Sol | Grok 4.3 | Delta |
|---|---|---|---|
| 1,000,000 | $8.00 | $1.56 | $6.44 (5.1×) |
| 10,000,000 | $80.00 | $15.63 | $64.38 (5.1×) |
| 100,000,000 | $800.00 | $156.25 | $643.75 (5.1×) |
Choose GPT-5.6 Sol if…
- ✓Strongest OpenAI model for agentic, long-horizon coding
- ✓Deep reasoning mode for multi-step planning
- ✓Native vision input and 1M context
- ✓Complex, multi-step professional and coding work where accuracy matters more than cost.
Choose Grok 4.3 if…
- ✓xAI’s general-purpose flagship
- ✓Extremely fast for its size
- ✓1M-token context
- ✓General-purpose work where speed and a huge context window both matter.
Run this exact matchup right now
Send the same prompt to GPT-5.6 Sol and Grok 4.3 side by side and see the outputs yourself.
Try GPT-5.6 Sol vs Grok 4.3 FreeWhat are common questions about GPT-5.6 Sol and Grok 4.3?
Is GPT-5.6 Sol cheaper than Grok 4.3?
Grok 4.3 is cheaper, at $1.56 per million blended tokens vs $8.00 for GPT-5.6 Sol.
Which has the bigger context window, GPT-5.6 Sol or Grok 4.3?
Both models support 1,000,000 tokens of context.
Can GPT-5.6 Sol replace Grok 4.3 for coding?
Both are viable for coding. Strongest OpenAI model for agentic, long-horizon coding (GPT-5.6 Sol) vs xAI’s general-purpose flagship (Grok 4.3) — pick based on which strength matters more for your workload.
Which is faster, GPT-5.6 Sol or Grok 4.3?
Grok 4.3 is faster: 98 t/s vs 44 t/s, measured on our speed benchmarks.
Neither of these? See GPT-5.6 Sol alternatives or Grok 4.3 alternatives.
What related comparisons help choose between GPT-5.6 Sol and Grok 4.3?
GPT-5.6 Sol pricingGrok 4.3 pricingvs GPT-4ovs Claude Opus 4.8vs DeepSeek V4 Provs Gemini 3.1 ProPremium model tests
Pricing verified 2026-05-19. Specs verified 2026-08-14.