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Comparison · 2 models · Updated Oct 4, 2026

GPT-5.4 nano vs Grok 4.3

Too close to call on our weighted score (GPT-5.4 nano 68, Grok 4.3 67). The right pick depends on what you value most.

  1. OpenAI

    GPT-5.4 nano

    Released Mar 17, 2026

    68/100
    • ECI145.8
    • Price$0.20 / $1.25
    • Context400K
    Full specs Remove GPT-5.4 nano

  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 (GPT-5.4 nano 68/100, Grok 4.3 67/100), so choose by what matters most for your work: Grok 4.3 for raw capability and GPT-5.4 nano 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-5.4 nano 145.8
  • Lowest priceGPT-5.4 nanoGPT-5.4 nano $0.463 · Grok 4.3 $1.56 per 1M tokens (3:1 blend)
  • Longest contextGrok 4.3Grok 4.3 1,000,000 · GPT-5.4 nano 400,000 tokens
  • Widest inputsGrok 4.3GPT-5.4 nano: Text, Images · Grok 4.3: Text, Images, PDFs
  • Self-hostingNo open weightsBoth are available only through APIs
How the score is built
MeasureWeightGPT-5.4 nanoGrok 4.3
CapabilityCapabilities Index (ECI)50%7377
Price25%6641
Inputs & features15%7080
Context window10%4460
Overall100%68/10067/100
02 — Side by side

Every spec in one table

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

GPT-5.4 nano vs Grok 4.3 specifications side by side
SpecificationGPT-5.4 nanoOpenAIGrok 4.3xAI
Capability
Capabilities Index (ECI)145.8149.2 (best)
ECI rank#75 of 148#55 of 148 (best)
GPQA DiamondGraduate-level science questions78.5%88.8% (best)
FrontierMath Tiers 1–3Research-level mathematics44.9% (best)42.8%
OTIS Mock AIME 2024–2025Competition mathematics87.8%93.3% (best)
SimpleQA VerifiedShort factual questions11.7%33.2% (best)
Price per million tokens
Input$0.20 (best)$1.25
Output$1.25 (best)$2.50
Cached input$0.02 (best)$0.20
Blended (3:1)$0.463 (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
ReasoningYeslow · medium · high · xhighYeslow · medium · high
Tool callingYesYes
Structured outputYesYes
Availability
WeightsProprietaryProprietary
API model IDgpt-5.4-nanogrok-4.3
API providers2627 (best)
ReleasedMar 17, 2026Apr 17, 2026
Knowledge cutoffAug 31, 2025—
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-5.4 nano$4.50
  • Grok 4.3$17.50
04 — Questions

Which should you choose?

Which is better: GPT-5.4 nano or Grok 4.3?

It is close. Our weighted score puts them within 1 points (GPT-5.4 nano 68/100, Grok 4.3 67/100), so choose by what matters most for your work: Grok 4.3 for raw capability and GPT-5.4 nano on price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

Which is cheaper, GPT-5.4 nano or Grok 4.3?

GPT-5.4 nano is cheaper at $0.20 input / $1.25 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 $0.463 per million tokens for GPT-5.4 nano versus $1.56 for Grok 4.3 (3.4× 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-5.4 nano 145.8 (#75 of 148). The confidence ranges of the top two overlap (147.6–150.8 vs 143.2–147.7), so treat the gap as small. On individual benchmarks: GPQA Diamond — Grok 4.3 88.8%, GPT-5.4 nano 78.5%; FrontierMath Tiers 1–3 — GPT-5.4 nano 44.9%, Grok 4.3 42.8%; OTIS Mock AIME 2024–2025 — Grok 4.3 93.3%, GPT-5.4 nano 87.8%; SimpleQA Verified — Grok 4.3 33.2%, GPT-5.4 nano 11.7%.

Which is better for coding?

There are no published SWE-bench Verified results for GPT-5.4 nano and 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-5.4 nano. Maximum output per response: GPT-5.4 nano up to 128,000, Grok 4.3 up to 30,000 tokens.

Which can read images, PDFs, audio or video?

GPT-5.4 nano 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-5.4 nano 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-5.4 nano came out Mar 17, 2026. Knowledge cutoff: GPT-5.4 nano Aug 31, 2025.

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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