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Comparison · 3 models · Updated Oct 4, 2026

GPT-5.4 mini vs Grok 4.3 vs o3-pro

Grok 4.3 comes out ahead, 67 to 63 and 51 on our weighted score, and it is the cheaper option too.

  1. OpenAI

    GPT-5.4 mini

    Released Mar 17, 2026

    63/100
    • ECI148.8
    • Price$0.75 / $4.50
    • Context400K
    Full specs Remove GPT-5.4 mini
  2. Our pick

    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. OpenAI

    o3-pro

    Released Jun 10, 2025

    51/100
    • ECI147.4
    • Price$20.00 / $80.00
    • Context200K
    Full specs Remove o3-pro
01 — Verdict

Grok 4.3 is our pick

Grok 4.3 is the better all-round choice, scoring 67/100 against GPT-5.4 mini (63) and o3-pro (51). It leads on inputs & features and context window. 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 mini 148.8 · o3-pro 147.4
  • Lowest priceGrok 4.3Grok 4.3 $1.56 · GPT-5.4 mini $1.69 · o3-pro $35.00 per 1M tokens (3:1 blend)
  • Longest contextGrok 4.3Grok 4.3 1,000,000 · GPT-5.4 mini 400,000 · o3-pro 200,000 tokens
  • Widest inputsGrok 4.3GPT-5.4 mini: Text, Images · Grok 4.3: Text, Images, PDFs · o3-pro: Text, Images
  • Self-hostingNo open weightsAll three are available only through APIs
How the score is built
MeasureWeightGPT-5.4 miniGrok 4.3o3-pro
CapabilityCapabilities Index (ECI)50%777775
Price25%39410
Inputs & features15%708070
Context window10%446032
Overall100%63/10067/10051/100
02 — Side by side

Every spec in one table

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

GPT-5.4 mini vs Grok 4.3 vs o3-pro specifications side by side
SpecificationGPT-5.4 miniOpenAIGrok 4.3xAIo3-proOpenAI
Capability
Capabilities Index (ECI)148.8149.2 (best)147.4
ECI rank#56 of 148#55 of 148 (best)#60 of 148
GPQA DiamondGraduate-level science questions86.9%88.8% (best)—
FrontierMath Tiers 1–3Research-level mathematics51.2% (best)42.8%—
OTIS Mock AIME 2024–2025Competition mathematics88.9%93.3% (best)—
SimpleQA VerifiedShort factual questions29.4%33.2% (best)—
Price per million tokens
Input$0.75 (best)$1.25$20.00
Output$4.50$2.50 (best)$80.00
Cached input$0.075 (best)$0.20—
Blended (3:1)$1.69$1.56 (best)$35.00
Long-context rateSame rateOver 200K: $2.50 / $5.00Same rate
Price sourceOfficial OpenAI APIOfficial xAI APIOfficial OpenAI API
Limits
Context window400,000 tokens1,000,000 tokens (best)200,000 tokens
Max output128,000 tokens (best)30,000 tokens100,000 tokens
Inputs and features
TextYesYesYes
ImagesYesYesYes
PDFsNoYesNo
AudioNoNoNo
VideoNoNoNo
ReasoningYeslow · medium · high · xhighYeslow · medium · highYeslow · medium · high
Tool callingYesYesYes
Structured outputYesYesYes
Availability
WeightsProprietaryProprietaryProprietary
API model IDgpt-5.4-minigrok-4.3o3-pro
API providers29 (best)276
ReleasedMar 17, 2026Apr 17, 2026Jun 10, 2025
Knowledge cutoffAug 31, 2025—May 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-5.4 mini$16.50
  • Grok 4.3$17.50
  • o3-pro$360.00
04 — Questions

Which should you choose?

Which is better: GPT-5.4 mini, Grok 4.3 or o3-pro?

Grok 4.3 is the better all-round choice, scoring 67/100 against GPT-5.4 mini (63) and o3-pro (51). It leads on inputs & features and context window. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

Which is cheaper, GPT-5.4 mini, Grok 4.3 or o3-pro?

Grok 4.3 is cheaper at $1.25 input / $2.50 output per million tokens (official xAI API price). GPT-5.4 mini costs $0.75 input / $4.50 output per million tokens (official OpenAI API price); o3-pro costs $20.00 input / $80.00 output per million tokens (official OpenAI API price). At a typical mix of three input tokens to one output token, that is $1.56 per million tokens for Grok 4.3 versus $1.69 for GPT-5.4 mini (1.1× as much) and $35.00 for o3-pro (22× 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), GPT-5.4 mini 148.8 (#56 of 148) and o3-pro 147.4 (#60 of 148). The confidence ranges of the top two overlap (147.6–150.8 vs 147.1–150.5), so treat the gap as small.

Which is better for coding?

There are no published SWE-bench Verified results for GPT-5.4 mini, Grok 4.3 and o3-pro 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. All three 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 mini and 200,000 for o3-pro. Maximum output per response: GPT-5.4 mini up to 128,000, Grok 4.3 up to 30,000, o3-pro up to 100,000 tokens.

Which can read images, PDFs, audio or video?

GPT-5.4 mini accepts text and images; Grok 4.3 accepts text, images and PDFs; o3-pro accepts text and images. Grok 4.3 handles the widest range of inputs.

Are any of these open source?

No. GPT-5.4 mini, Grok 4.3 and o3-pro 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 mini came out Mar 17, 2026; o3-pro came out Jun 10, 2025. Knowledge cutoff: GPT-5.4 mini Aug 31, 2025, o3-pro May 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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