ZMIME
Comparison · 3 models · Updated Oct 4, 2026

Grok 4.3 vs Gemini Robotics-ER 1.6 Preview vs GPT-5.4 mini

Grok 4.3 comes out ahead, 56 to 50 and 49 on our weighted score, and it is the cheaper option too.

  1. Our pick

    xAI

    Grok 4.3

    Released Apr 17, 2026

    56/100
    • ECI149.2
    • Price$1.25 / $2.50
    • Context1M
    Full specs Remove Grok 4.3

  2. Google

    Gemini Robotics-ER 1.6 Preview

    Released Apr 14, 2026

    50/100
    • ECI—
    • Price$1.00 / $5.00
    • Context131K
    Full specs Remove Gemini Robotics-ER 1.6 Preview

  3. OpenAI

    GPT-5.4 mini

    Released Mar 17, 2026

    49/100
    • ECI148.8
    • Price$0.75 / $4.50
    • Context400K
    Full specs Remove GPT-5.4 mini
01 — Verdict

Grok 4.3 is our pick

Grok 4.3 is the better all-round choice, scoring 56/100 against Gemini Robotics-ER 1.6 Preview (50) and GPT-5.4 mini (49). It leads on context window. Gemini Robotics-ER 1.6 Preview wins on inputs & features. The score weighs price 50%, inputs & features 30%, context window 20%. None of the shared benchmarks cover every model here yet, so capability is left out of this verdict.

  • CapabilityNot enough dataNo independent benchmark covers every model here yet
  • Lowest priceGrok 4.3Grok 4.3 $1.56 · GPT-5.4 mini $1.69 · Gemini Robotics-ER 1.6 Preview $2.00 per 1M tokens (3:1 blend)
  • Longest contextGrok 4.3Grok 4.3 1,000,000 · GPT-5.4 mini 400,000 · Gemini Robotics-ER 1.6 Preview 131,072 tokens
  • Widest inputsGemini Robotics-ER 1.6 PreviewGrok 4.3: Text, Images, PDFs · Gemini Robotics-ER 1.6 Preview: Text, Images, Audio, Video · GPT-5.4 mini: Text, Images
  • Self-hostingNo open weightsAll three are available only through APIs
How the score is built
MeasureWeightGrok 4.3Gemini Robotics-ER 1.6 PreviewGPT-5.4 mini
Price50%413639
Inputs & features30%809070
Context window20%602444
Overall100%56/10050/10049/100

Left out because at least one model lacks the data: capability. The remaining weights were rescaled.

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 Gemini Robotics-ER 1.6 Preview vs GPT-5.4 mini specifications side by side
SpecificationGrok 4.3xAIGemini Robotics-ER 1.6 PreviewGoogleGPT-5.4 miniOpenAI
Capability
Capabilities Index (ECI)149.2 (best)—148.8
ECI rank#55 of 148 (best)—#56 of 148
GPQA DiamondGraduate-level science questions88.8% (best)—86.9%
FrontierMath Tiers 1–3Research-level mathematics42.8%—51.2% (best)
OTIS Mock AIME 2024–2025Competition mathematics93.3% (best)—88.9%
SimpleQA VerifiedShort factual questions33.2% (best)—29.4%
Price per million tokens
Input$1.25$1.00$0.75 (best)
Output$2.50 (best)$5.00$4.50
Cached input$0.20—$0.075 (best)
Blended (3:1)$1.56 (best)$2.00$1.69
Long-context rateOver 200K: $2.50 / $5.00Same rateSame rate
Price sourceOfficial xAI APIMedian of 1 providersOfficial OpenAI API
Limits
Context window1,000,000 tokens (best)131,072 tokens400,000 tokens
Max output30,000 tokens65,536 tokens128,000 tokens (best)
Inputs and features
TextYesYesYes
ImagesYesYesYes
PDFsYesNoNo
AudioNoYesNo
VideoNoYesNo
ReasoningYeslow · medium · highYesYeslow · medium · high · xhigh
Tool callingYesYesYes
Structured outputYesYesYes
Availability
WeightsProprietaryProprietaryProprietary
API model IDgrok-4.3—gpt-5.4-mini
API providers27129 (best)
ReleasedApr 17, 2026Apr 14, 2026Mar 17, 2026
Knowledge cutoff—Jan 2025Aug 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
  • Gemini Robotics-ER 1.6 Preview$20.00
  • GPT-5.4 mini$16.50
04 — Questions

Which should you choose?

Which is better: Grok 4.3, Gemini Robotics-ER 1.6 Preview or GPT-5.4 mini?

Grok 4.3 is the better all-round choice, scoring 56/100 against Gemini Robotics-ER 1.6 Preview (50) and GPT-5.4 mini (49). It leads on context window. Gemini Robotics-ER 1.6 Preview wins on inputs & features. The score weighs price 50%, inputs & features 30%, context window 20%. None of the shared benchmarks cover every model here yet, so capability is left out of this verdict.

Which is cheaper, Grok 4.3, Gemini Robotics-ER 1.6 Preview or GPT-5.4 mini?

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); Gemini Robotics-ER 1.6 Preview costs $1.00 input / $5.00 output per million tokens (median across 1 API provider). 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 $2.00 for Gemini Robotics-ER 1.6 Preview (1.3× as much).

Which scores higher on benchmarks?

There is no independent benchmark that covers all three models yet. Grok 4.3 has an ECI of 149.2, Gemini Robotics-ER 1.6 Preview has not been scored yet and GPT-5.4 mini has an ECI of 148.8.

Which is better for coding?

There are no published SWE-bench Verified results for Grok 4.3, Gemini Robotics-ER 1.6 Preview and GPT-5.4 mini yet, so there is no like-for-like coding score. Test both on a sample of your own tasks. 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 131,072 for Gemini Robotics-ER 1.6 Preview. Maximum output per response: Grok 4.3 up to 30,000, Gemini Robotics-ER 1.6 Preview up to 65,536, 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; Gemini Robotics-ER 1.6 Preview accepts text, images, audio and video; GPT-5.4 mini accepts text and images. Gemini Robotics-ER 1.6 Preview handles the widest range of inputs.

Are any of these open source?

No. Grok 4.3, Gemini Robotics-ER 1.6 Preview 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. Gemini Robotics-ER 1.6 Preview came out Apr 14, 2026; GPT-5.4 mini came out Mar 17, 2026. Knowledge cutoff: Gemini Robotics-ER 1.6 Preview Jan 2025, 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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