ZMIME
Comparison · 2 models · Updated Oct 4, 2026

GPT-5 Mini vs Grok 4.3

Too close to call on our weighted score (Grok 4.3 67, GPT-5 Mini 65). The right pick depends on what you value most.

  1. OpenAI

    GPT-5 Mini

    Released Aug 7, 2025

    65/100
    • ECI145.5
    • Price$0.25 / $2.00
    • Context400K
    Full specs Remove GPT-5 Mini

  2. xAI

    Grok 4.3

    Released Apr 17, 2026

    67/100
    • ECI149.2
    • Price$1.25 / $2.50
    • Context1M
    Full specs Remove Grok 4.3

  3. Add a model

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01 — Verdict

Too close to call

It is close. Our weighted score puts them within 1 points (Grok 4.3 67/100, GPT-5 Mini 65/100), so choose by what matters most for your work: Grok 4.3 for raw capability and GPT-5 Mini on price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

  • CapabilityGrok 4.3Capabilities Index (ECI): Grok 4.3 149.2 · GPT-5 Mini 145.5
  • Lowest priceGPT-5 MiniGPT-5 Mini $0.688 · Grok 4.3 $1.56 per 1M tokens (3:1 blend)
  • Longest contextGrok 4.3Grok 4.3 1,000,000 · GPT-5 Mini 400,000 tokens
  • Widest inputsGrok 4.3GPT-5 Mini: Text, Images · Grok 4.3: Text, Images, PDFs
  • Self-hostingNo open weightsBoth are available only through APIs
How the score is built
MeasureWeightGPT-5 MiniGrok 4.3
CapabilityCapabilities Index (ECI)50%7277
Price25%5841
Inputs & features15%7080
Context window10%4460
Overall100%65/10067/100
02 — Side by side

Every spec in one table

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

GPT-5 Mini vs Grok 4.3 specifications side by side
SpecificationGPT-5 MiniOpenAIGrok 4.3xAI
Capability
Capabilities Index (ECI)145.5149.2 (best)
ECI rank#77 of 148#55 of 148 (best)
GPQA DiamondGraduate-level science questions75.0%88.8% (best)
FrontierMath Tiers 1–3Research-level mathematics46.7% (best)42.8%
OTIS Mock AIME 2024–2025Competition mathematics86.7%93.3% (best)
SWE-bench VerifiedFixing real GitHub issues64.7%—
SimpleQA VerifiedShort factual questions21.6%33.2% (best)
Price per million tokens
Input$0.25 (best)$1.25
Output$2.00 (best)$2.50
Cached input$0.025 (best)$0.20
Blended (3:1)$0.688 (best)$1.56
Long-context rateSame rateOver 200K: $2.50 / $5.00
Price sourceOfficial OpenAI APIOfficial xAI API
Limits
Context window400,000 tokens1,000,000 tokens (best)
Max output128,000 tokens (best)30,000 tokens
Inputs and features
TextYesYes
ImagesYesYes
PDFsNoYes
AudioNoNo
VideoNoNo
ReasoningYesminimal · low · medium · highYeslow · medium · high
Tool callingYesYes
Structured outputYesYes
Availability
WeightsProprietaryProprietary
API model IDgpt-5-minigrok-4.3
API providers2327 (best)
ReleasedAug 7, 2025Apr 17, 2026
Knowledge cutoffMay 30, 2024—
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 Mini$6.50
  • Grok 4.3$17.50
04 — Questions

Which should you choose?

Which is better: GPT-5 Mini or Grok 4.3?

It is close. Our weighted score puts them within 1 points (Grok 4.3 67/100, GPT-5 Mini 65/100), so choose by what matters most for your work: Grok 4.3 for raw capability and GPT-5 Mini on price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

Which is cheaper, GPT-5 Mini or Grok 4.3?

GPT-5 Mini is cheaper at $0.25 input / $2.00 output per million tokens (official OpenAI API price). Grok 4.3 costs $1.25 input / $2.50 output per million tokens (official xAI API price). At a typical mix of three input tokens to one output token, that is $0.688 per million tokens for GPT-5 Mini versus $1.56 for Grok 4.3 (2.3× as much).

Which scores higher on benchmarks?

Grok 4.3 scores higher on the Capabilities Index (ECI): Grok 4.3 149.2 (#55 of 148) and GPT-5 Mini 145.5 (#77 of 148). Their confidence ranges do not overlap (147.6–150.8 vs 143.6–147.0), so the gap is a real one. On individual benchmarks: GPQA Diamond — Grok 4.3 88.8%, GPT-5 Mini 75.0%; FrontierMath Tiers 1–3 — GPT-5 Mini 46.7%, Grok 4.3 42.8%; OTIS Mock AIME 2024–2025 — Grok 4.3 93.3%, GPT-5 Mini 86.7%; SimpleQA Verified — Grok 4.3 33.2%, GPT-5 Mini 21.6%.

Which is better for coding?

There are no published SWE-bench Verified results for Grok 4.3 yet, so there is no like-for-like coding score. On overall capability, Grok 4.3 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?

Grok 4.3 has the largest context window at 1,000,000 tokens, against 400,000 for GPT-5 Mini. Maximum output per response: GPT-5 Mini up to 128,000, Grok 4.3 up to 30,000 tokens.

Which can read images, PDFs, audio or video?

GPT-5 Mini accepts text and images; Grok 4.3 accepts text, images and PDFs. Grok 4.3 handles the widest range of inputs.

Are any of these open source?

No. GPT-5 Mini and Grok 4.3 are proprietary and only available through APIs and apps.

Which is newer?

Grok 4.3 is the newest, released Apr 17, 2026. GPT-5 Mini came out Aug 7, 2025. Knowledge cutoff: GPT-5 Mini May 30, 2024.

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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