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Comparison · 3 models · Updated Oct 4, 2026

Grok 4.3 vs Grok 4.20 (Reasoning) vs GPT-5.4 mini

Too close to call on our weighted score (Grok 4.20 (Reasoning) 68, Grok 4.3 67, GPT-5.4 mini 63). The right pick depends on what you value most.

  1. xAI

    Grok 4.3

    Released Apr 17, 2026

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

  2. xAI

    Grok 4.20 (Reasoning)

    Released Mar 9, 2026

    68/100
    • ECI152.0
    • Price$1.25 / $2.50
    • Context1M
    Full specs Remove Grok 4.20 (Reasoning)

  3. 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
01 — Verdict

Too close to call

It is close. Our weighted score puts them within 2 points (Grok 4.20 (Reasoning) 68/100, Grok 4.3 67/100, GPT-5.4 mini 63/100), so choose by what matters most for your work: Grok 4.20 (Reasoning) for raw capability and Grok 4.3 on price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

  • CapabilityGrok 4.20 (Reasoning)Capabilities Index (ECI): Grok 4.20 (Reasoning) 152.0 · Grok 4.3 149.2 · GPT-5.4 mini 148.8
  • Lowest priceGrok 4.3 and Grok 4.20 (Reasoning)Grok 4.3 $1.56 · Grok 4.20 (Reasoning) $1.56 · GPT-5.4 mini $1.69 per 1M tokens (3:1 blend)
  • Longest contextGrok 4.3 and Grok 4.20 (Reasoning)Grok 4.3 1,000,000 · Grok 4.20 (Reasoning) 1,000,000 · GPT-5.4 mini 400,000 tokens
  • Widest inputsGrok 4.3 and Grok 4.20 (Reasoning)Grok 4.3: Text, Images, PDFs · Grok 4.20 (Reasoning): Text, Images, PDFs · GPT-5.4 mini: Text, Images
  • Self-hostingNo open weightsAll three are available only through APIs
How the score is built
MeasureWeightGrok 4.3Grok 4.20 (Reasoning)GPT-5.4 mini
CapabilityCapabilities Index (ECI)50%778177
Price25%414139
Inputs & features15%808070
Context window10%606044
Overall100%67/10068/10063/100
02 — Side by side

Every spec in one table

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

Grok 4.3 vs Grok 4.20 (Reasoning) vs GPT-5.4 mini specifications side by side
SpecificationGrok 4.3xAIGrok 4.20 (Reasoning)xAIGPT-5.4 miniOpenAI
Capability
Capabilities Index (ECI)149.2152.0 (best)148.8
ECI rank#55 of 148#41 of 148 (best)#56 of 148
GPQA DiamondGraduate-level science questions88.8%89.3% (best)86.9%
FrontierMath Tiers 1–3Research-level mathematics42.8%44.9%51.2% (best)
OTIS Mock AIME 2024–2025Competition mathematics93.3% (best)92.2%88.9%
SimpleQA VerifiedShort factual questions33.2% (best)30.2%29.4%
Price per million tokens
Input$1.25$1.25$0.75 (best)
Output$2.50 (best)$2.50 (best)$4.50
Cached input$0.20$0.20$0.075 (best)
Blended (3:1)$1.56 (best)$1.56 (best)$1.69
Long-context rateOver 200K: $2.50 / $5.00Over 200K: $2.50 / $5.00Same rate
Price sourceOfficial xAI APIOfficial xAI APIOfficial OpenAI API
Limits
Context window1,000,000 tokens (best)1,000,000 tokens (best)400,000 tokens
Max output30,000 tokens30,000 tokens128,000 tokens (best)
Inputs and features
TextYesYesYes
ImagesYesYesYes
PDFsYesYesNo
AudioNoNoNo
VideoNoNoNo
ReasoningYeslow · medium · highYesYeslow · medium · high · xhigh
Tool callingYesYesYes
Structured outputYesYesYes
Availability
WeightsProprietaryProprietaryProprietary
API model IDgrok-4.3grok-4.20-0309-reasoninggpt-5.4-mini
API providers271129 (best)
ReleasedApr 17, 2026Mar 9, 2026Mar 17, 2026
Knowledge cutoff——Aug 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.

  • Grok 4.3$17.50
  • Grok 4.20 (Reasoning)$17.50
  • GPT-5.4 mini$16.50
04 — Questions

Which should you choose?

Which is better: Grok 4.3, Grok 4.20 (Reasoning) or GPT-5.4 mini?

It is close. Our weighted score puts them within 2 points (Grok 4.20 (Reasoning) 68/100, Grok 4.3 67/100, GPT-5.4 mini 63/100), so choose by what matters most for your work: Grok 4.20 (Reasoning) for raw capability and Grok 4.3 on price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

Which is cheaper, Grok 4.3, Grok 4.20 (Reasoning) or GPT-5.4 mini?

Grok 4.3 is cheaper at $1.25 input / $2.50 output per million tokens (official xAI API price). Grok 4.20 (Reasoning) costs $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). At a typical mix of three input tokens to one output token, that is $1.56 per million tokens for Grok 4.3 versus $1.56 for Grok 4.20 (Reasoning) (1× as much) and $1.69 for GPT-5.4 mini (1.1× as much).

Which scores higher on benchmarks?

Grok 4.20 (Reasoning) scores higher on the Capabilities Index (ECI): Grok 4.20 (Reasoning) 152.0 (#41 of 148), Grok 4.3 149.2 (#55 of 148) and GPT-5.4 mini 148.8 (#56 of 148). The confidence ranges of the top two overlap (149.3–154.4 vs 147.6–150.8), so treat the gap as small. On individual benchmarks: GPQA Diamond — Grok 4.20 (Reasoning) 89.3%, Grok 4.3 88.8%, GPT-5.4 mini 86.9%; FrontierMath Tiers 1–3 — GPT-5.4 mini 51.2%, Grok 4.20 (Reasoning) 44.9%, Grok 4.3 42.8%; OTIS Mock AIME 2024–2025 — Grok 4.3 93.3%, Grok 4.20 (Reasoning) 92.2%, GPT-5.4 mini 88.9%; SimpleQA Verified — Grok 4.3 33.2%, Grok 4.20 (Reasoning) 30.2%, GPT-5.4 mini 29.4%.

Which is better for coding?

There are no published SWE-bench Verified results for Grok 4.3, Grok 4.20 (Reasoning) and GPT-5.4 mini yet, so there is no like-for-like coding score. On overall capability, Grok 4.20 (Reasoning) 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 and Grok 4.20 (Reasoning) have the largest context windows (1,000,000 and 1,000,000 tokens), against 400,000 for GPT-5.4 mini. Maximum output per response: Grok 4.3 up to 30,000, Grok 4.20 (Reasoning) up to 30,000, GPT-5.4 mini up to 128,000 tokens.

Which can read images, PDFs, audio or video?

Grok 4.3 accepts text, images and PDFs; Grok 4.20 (Reasoning) accepts text, images and PDFs; GPT-5.4 mini accepts text and images. Grok 4.3 handles the widest range of inputs.

Are any of these open source?

No. Grok 4.3, Grok 4.20 (Reasoning) and GPT-5.4 mini 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; Grok 4.20 (Reasoning) came out Mar 9, 2026. Knowledge cutoff: GPT-5.4 mini 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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