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Comparison · 3 models · Updated Oct 4, 2026

GPT-5.4 Pro vs Gemini 3.1 Pro Preview vs Claude Fable 5

Gemini 3.1 Pro Preview comes out ahead, 68 to 65 and 60 on our weighted score, and it is the cheaper option too.

  1. OpenAI

    GPT-5.4 Pro

    Released Mar 5, 2026

    60/100
    • ECI159.1
    • Price$30.00 / $180.00
    • Context1.05M
  2. Our pick

    Google

    Gemini 3.1 Pro Preview

    Released Feb 19, 2026

    68/100
    • ECI154.8
    • Price$2.00 / $12.00
    • Context1.05M
  3. Anthropic

    Claude Fable 5

    Released Jun 9, 2026

    65/100
    • ECI162.2
    • Price$10.00 / $50.00
    • Context1M
01 — Verdict

Gemini 3.1 Pro Preview is our pick

Gemini 3.1 Pro Preview is the better all-round choice, scoring 68/100 against Claude Fable 5 (65) and GPT-5.4 Pro (60). It leads on price and inputs & features. Claude Fable 5 wins on capability. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

  • CapabilityClaude Fable 5Capabilities Index (ECI): Claude Fable 5 162.2 · GPT-5.4 Pro 159.1 · Gemini 3.1 Pro Preview 154.8
  • Lowest priceGemini 3.1 Pro PreviewGemini 3.1 Pro Preview $4.50 · Claude Fable 5 $20.00 · GPT-5.4 Pro $67.50 per 1M tokens (3:1 blend)
  • Longest contextGPT-5.4 Pro and Gemini 3.1 Pro PreviewGPT-5.4 Pro 1,050,000 · Gemini 3.1 Pro Preview 1,048,576 · Claude Fable 5 1,000,000 tokens
  • Widest inputsGemini 3.1 Pro PreviewGPT-5.4 Pro: Text, Images · Gemini 3.1 Pro Preview: Text, Images, PDFs, Audio, Video · Claude Fable 5: Text, Images, PDFs
  • Self-hostingNo open weightsAll three are available only through APIs
How the score is built
MeasureWeightGPT-5.4 ProGemini 3.1 Pro PreviewClaude Fable 5
CapabilityCapabilities Index (ECI)50%908494
Price25%0190
Inputs & features15%6010080
Context window10%616160
Overall100%60/10068/10065/100
02 — Side by side

Every spec in one table

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

GPT-5.4 Pro vs Gemini 3.1 Pro Preview vs Claude Fable 5 specifications side by side
SpecificationGPT-5.4 ProOpenAIGemini 3.1 Pro PreviewGoogleClaude Fable 5Anthropic
Capability
Capabilities Index (ECI)159.1154.8162.2 (best)
ECI rank#11 of 148#31 of 148#7 of 148 (best)
GPQA DiamondGraduate-level science questions94.6% (best)94.4%85.9%
FrontierMath Tiers 1–3Research-level mathematics82.5%59.7%87.0% (best)
OTIS Mock AIME 2024–2025Competition mathematics—95.6%100% (best)
SWE-bench VerifiedFixing real GitHub issues—75.6%—
SimpleQA VerifiedShort factual questions46.3%73.5% (best)70.7%
Price per million tokens
Input$30.00$2.00 (best)$10.00
Output$180.00$12.00 (best)$50.00
Cached input—$0.20 (best)$1.00
Blended (3:1)$67.50$4.50 (best)$20.00
Long-context rateOver 272K: $60.00 / $270.00Over 200K: $4.00 / $18.00Same rate
Price sourceOfficial OpenAI APIOfficial Google APIOfficial Anthropic API
Limits
Context window1,050,000 tokens (best)1,048,576 tokens1,000,000 tokens
Max output128,000 tokens (best)65,536 tokens128,000 tokens (best)
Inputs and features
TextYesYesYes
ImagesYesYesYes
PDFsNoYesYes
AudioNoYesNo
VideoNoYesNo
ReasoningYesmedium · high · xhighYeslow · medium · highYeslow · medium · high · xhigh · max
Tool callingYesYesYes
Structured outputNoYesYes
Availability
WeightsProprietaryProprietaryProprietary
API model IDgpt-5.4-progemini-3.1-pro-previewclaude-fable-5
API providers162638 (best)
ReleasedMar 5, 2026Feb 19, 2026Jun 9, 2026
Knowledge cutoffAug 31, 2025Jan 2025Jan 31, 2026
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 Pro$660.00
  • Gemini 3.1 Pro Preview$44.00
  • Claude Fable 5$200.00
04 — Questions

Which should you choose?

Which is better: GPT-5.4 Pro, Gemini 3.1 Pro Preview or Claude Fable 5?

Gemini 3.1 Pro Preview is the better all-round choice, scoring 68/100 against Claude Fable 5 (65) and GPT-5.4 Pro (60). It leads on price and inputs & features. Claude Fable 5 wins on capability. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

Which is cheaper, GPT-5.4 Pro, Gemini 3.1 Pro Preview or Claude Fable 5?

Gemini 3.1 Pro Preview is cheaper at $2.00 input / $12.00 output per million tokens (official Google API price). Claude Fable 5 costs $10.00 input / $50.00 output per million tokens (official Anthropic API price); GPT-5.4 Pro costs $30.00 input / $180.00 output per million tokens (official OpenAI API price). At a typical mix of three input tokens to one output token, that is $4.50 per million tokens for Gemini 3.1 Pro Preview versus $20.00 for Claude Fable 5 (4.4× as much) and $67.50 for GPT-5.4 Pro (15× as much).

Which scores higher on benchmarks?

Claude Fable 5 scores higher on the Capabilities Index (ECI): Claude Fable 5 162.2 (#7 of 148), GPT-5.4 Pro 159.1 (#11 of 148) and Gemini 3.1 Pro Preview 154.8 (#31 of 148). The confidence ranges of the top two overlap (159.6–166.1 vs 156.5–161.9), so treat the gap as small. On individual benchmarks: GPQA Diamond — GPT-5.4 Pro 94.6%, Gemini 3.1 Pro Preview 94.4%, Claude Fable 5 85.9%; FrontierMath Tiers 1–3 — Claude Fable 5 87.0%, GPT-5.4 Pro 82.5%, Gemini 3.1 Pro Preview 59.7%; SimpleQA Verified — Gemini 3.1 Pro Preview 73.5%, Claude Fable 5 70.7%, GPT-5.4 Pro 46.3%.

Which is better for coding?

There are no published SWE-bench Verified results for GPT-5.4 Pro and Claude Fable 5 yet, so there is no like-for-like coding score. On overall capability, Claude Fable 5 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?

GPT-5.4 Pro and Gemini 3.1 Pro Preview have the largest context windows (1,050,000 and 1,048,576 tokens), against 1,000,000 for Claude Fable 5. Maximum output per response: GPT-5.4 Pro up to 128,000, Gemini 3.1 Pro Preview up to 65,536, Claude Fable 5 up to 128,000 tokens.

Which can read images, PDFs, audio or video?

GPT-5.4 Pro accepts text and images; Gemini 3.1 Pro Preview accepts text, images, PDFs, audio and video; Claude Fable 5 accepts text, images and PDFs. Gemini 3.1 Pro Preview handles the widest range of inputs.

Are any of these open source?

No. GPT-5.4 Pro, Gemini 3.1 Pro Preview and Claude Fable 5 are proprietary and only available through APIs and apps.

Which is newer?

Claude Fable 5 is the newest, released Jun 9, 2026. GPT-5.4 Pro came out Mar 5, 2026; Gemini 3.1 Pro Preview came out Feb 19, 2026. Knowledge cutoff: GPT-5.4 Pro Aug 31, 2025, Gemini 3.1 Pro Preview Jan 2025, Claude Fable 5 Jan 31, 2026.

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.