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Comparison · 2 models · Updated Oct 4, 2026

GPT-5.6 Sol vs Grok 4.6

Too close to call on our weighted score (GPT-5.6 Sol 66, Grok 4.6 65). The right pick depends on what you value most.

  1. OpenAI

    GPT-5.6 Sol

    Released Jul 9, 2026

    66/100
    • ECI161.8
    • Price$4.00 / $20.00
    • Context1.05M
    Full specs Remove GPT-5.6 Sol

  2. xAI

    Grok 4.6

    Released Aug 12, 2026

    65/100
    • ECI156.6
    • Price$2.00 / $6.00
    • Context500K
    Full specs Remove Grok 4.6

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01 — Verdict

Too close to call

It is close. Our weighted score puts them within 1 points (GPT-5.6 Sol 66/100, Grok 4.6 65/100), so choose by what matters most for your work: GPT-5.6 Sol for raw capability and Grok 4.6 on price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

  • CapabilityGPT-5.6 SolCapabilities Index (ECI): GPT-5.6 Sol 161.8 · Grok 4.6 156.6
  • Lowest priceGrok 4.6Grok 4.6 $3.00 · GPT-5.6 Sol $8.00 per 1M tokens (3:1 blend)
  • Longest contextGPT-5.6 SolGPT-5.6 Sol 1,050,000 · Grok 4.6 500,000 tokens
  • Widest inputsGPT-5.6 SolGPT-5.6 Sol: Text, Images, PDFs · Grok 4.6: Text, Images
  • Self-hostingNo open weightsBoth are available only through APIs
How the score is built
MeasureWeightGPT-5.6 SolGrok 4.6
CapabilityCapabilities Index (ECI)50%9386
Price25%727
Inputs & features15%8070
Context window10%6148
Overall100%66/10065/100
02 — Side by side

Every spec in one table

Highlighted cells lead their row. Dashes mean the data is not published.

GPT-5.6 Sol vs Grok 4.6 specifications side by side
SpecificationGPT-5.6 SolOpenAIGrok 4.6xAI
Capability
Capabilities Index (ECI)161.8 (best)156.6
ECI rank#8 of 148 (best)#19 of 148
GPQA DiamondGraduate-level science questions93.5%94.0% (best)
FrontierMath Tiers 1–3Research-level mathematics89.1% (best)66.0%
OTIS Mock AIME 2024–2025Competition mathematics100% (best)99.2%
SimpleQA VerifiedShort factual questions69.7% (best)49.3%
Price per million tokens
Input$4.00$2.00 (best)
Output$20.00$6.00 (best)
Cached input$0.40 (best)$0.50
Blended (3:1)$8.00$3.00 (best)
Long-context rateOver 272K: $8.00 / $30.00Over 200K: $4.00 / $12.00
Price sourceOfficial OpenAI APIOfficial xAI API
Limits
Context window1,050,000 tokens (best)500,000 tokens
Max output128,000 tokens500,000 tokens (best)
Inputs and features
TextYesYes
ImagesYesYes
PDFsYesNo
AudioNoNo
VideoNoNo
ReasoningYeslow · medium · high · xhigh · maxYeslow · medium · high · xhigh
Tool callingYesYes
Structured outputYesYes
Availability
WeightsProprietaryProprietary
API model IDgpt-5.6-solgrok-4.6
API providers40 (best)29
ReleasedJul 9, 2026Aug 12, 2026
Knowledge cutoffFeb 16, 2026Feb 1, 2026
03 — Cost

What would a month cost?

Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.

  • GPT-5.6 Sol$80.00
  • Grok 4.6$32.00
04 — Questions

Which should you choose?

Which is better: GPT-5.6 Sol or Grok 4.6?

It is close. Our weighted score puts them within 1 points (GPT-5.6 Sol 66/100, Grok 4.6 65/100), so choose by what matters most for your work: GPT-5.6 Sol for raw capability and Grok 4.6 on price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

Which is cheaper, GPT-5.6 Sol or Grok 4.6?

Grok 4.6 is cheaper at $2.00 input / $6.00 output per million tokens (official xAI API price). GPT-5.6 Sol costs $4.00 input / $20.00 output per million tokens (official OpenAI API price). At a typical mix of three input tokens to one output token, that is $3.00 per million tokens for Grok 4.6 versus $8.00 for GPT-5.6 Sol (2.7× as much).

Which scores higher on benchmarks?

GPT-5.6 Sol scores higher on the Capabilities Index (ECI): GPT-5.6 Sol 161.8 (#8 of 148) and Grok 4.6 156.6 (#19 of 148). Their confidence ranges do not overlap (159.3–165.3 vs 154.7–158.9), so the gap is a real one. On individual benchmarks: GPQA Diamond — Grok 4.6 94.0%, GPT-5.6 Sol 93.5%; FrontierMath Tiers 1–3 — GPT-5.6 Sol 89.1%, Grok 4.6 66.0%; OTIS Mock AIME 2024–2025 — GPT-5.6 Sol 100%, Grok 4.6 99.2%; SimpleQA Verified — GPT-5.6 Sol 69.7%, Grok 4.6 49.3%.

Which is better for coding?

There are no published SWE-bench Verified results for GPT-5.6 Sol and Grok 4.6 yet, so there is no like-for-like coding score. On overall capability, GPT-5.6 Sol leads, which tends to carry over to coding, but test on your own codebase. Both support tool calling for agent workflows.

Which has the bigger context window?

GPT-5.6 Sol has the largest context window at 1,050,000 tokens, against 500,000 for Grok 4.6. Maximum output per response: GPT-5.6 Sol up to 128,000, Grok 4.6 up to 500,000 tokens.

Which can read images, PDFs, audio or video?

GPT-5.6 Sol accepts text, images and PDFs; Grok 4.6 accepts text and images. GPT-5.6 Sol handles the widest range of inputs.

Are any of these open source?

No. GPT-5.6 Sol and Grok 4.6 are proprietary and only available through APIs and apps.

Which is newer?

Grok 4.6 is the newest, released Aug 12, 2026. GPT-5.6 Sol came out Jul 9, 2026. Knowledge cutoff: GPT-5.6 Sol Feb 16, 2026, Grok 4.6 Feb 1, 2026.

How do you decide the winner?

Each model gets a 0–100 score on capability (50%, independent benchmark results); price (25%, blended price per million tokens (3 input : 1 output), log scale); inputs & features (15%, image, PDF, audio and video input, tool calling, structured output and reasoning); context window (10%, maximum tokens per request, log scale). Dimensions missing for any model are dropped and the remaining weights rescaled, so every model is judged on the same evidence. Specs and prices come from public model listings and the labs’ own API pages; capability scores come from independent benchmark runs. Data updated Oct 4, 2026.

05 — Keep comparing

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