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Comparison · 2 models · Updated Oct 4, 2026

GPT-5.1 Chat vs Kimi K2 Thinking Turbo

GPT-5.1 Chat comes out ahead, 52 to 36 on our weighted score, and it is the cheaper option too.

  1. Our pick

    OpenAI

    GPT-5.1 Chat

    Released Nov 13, 2025

    52/100
    • ECI—
    • Price$1.25 / $10.00
    • Context128K
  2. Moonshot AI

    Kimi K2 Thinking Turbo

    Released Nov 6, 2025

    36/100
    • ECI—
    • Price—
    • Context262K
  3. Add a model

    Make it a three-way comparison.

01 — Verdict

GPT-5.1 Chat is our pick

GPT-5.1 Chat is the better all-round choice, scoring 52/100 against Kimi K2 Thinking Turbo (36). It leads on inputs & features. Kimi K2 Thinking Turbo wins on context window. The score weighs inputs & features 60%, context window 40%. 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 priceGPT-5.1 ChatGPT-5.1 Chat $3.44 per 1M tokens (3:1 blend) · Kimi K2 Thinking Turbo unpriced
  • Longest contextKimi K2 Thinking TurboKimi K2 Thinking Turbo 262,144 · GPT-5.1 Chat 128,000 tokens
  • Widest inputsGPT-5.1 ChatGPT-5.1 Chat: Text, Images · Kimi K2 Thinking Turbo: Text
  • Self-hostingKimi K2 Thinking TurboPublishes downloadable weights
How the score is built
MeasureWeightGPT-5.1 ChatKimi K2 Thinking Turbo
Inputs & features60%7035
Context window40%2437
Overall100%52/10036/100

Left out because at least one model lacks the data: capability and price. 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.

GPT-5.1 Chat vs Kimi K2 Thinking Turbo specifications side by side
SpecificationGPT-5.1 ChatOpenAIKimi K2 Thinking TurboMoonshot AI
Capability
Capabilities Index (ECI)——
ECI rank——
Price per million tokens
Input$1.25—
Output$10.00—
Cached input——
Blended (3:1)$3.44—
Long-context rateSame rate—
Price sourceMedian of 2 providers—
Limits
Context window128,000 tokens262,144 tokens (best)
Max output16,384 tokens262,144 tokens (best)
Inputs and features
TextYesYes
ImagesYesNo
PDFsNoNo
AudioNoNo
VideoNoNo
ReasoningYesYes
Tool callingYesYes
Structured outputYesNo
Availability
WeightsProprietaryOpen
API model ID——
API providers2—
ReleasedNov 13, 2025Nov 6, 2025
Knowledge cutoffSep 30, 2024Aug 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-5.1 Chat$32.50
  • Kimi K2 Thinking Turbo—
04 — Questions

Which should you choose?

Which is better: GPT-5.1 Chat or Kimi K2 Thinking Turbo?

GPT-5.1 Chat is the better all-round choice, scoring 52/100 against Kimi K2 Thinking Turbo (36). It leads on inputs & features. Kimi K2 Thinking Turbo wins on context window. The score weighs inputs & features 60%, context window 40%. None of the shared benchmarks cover every model here yet, so capability is left out of this verdict.

Which is cheaper, GPT-5.1 Chat or Kimi K2 Thinking Turbo?

GPT-5.1 Chat is cheaper at $1.25 input / $10.00 output per million tokens (median across 2 API providers). . At a typical mix of three input tokens to one output token, that is $3.44 per million tokens for GPT-5.1 Chat versus . Kimi K2 Thinking Turbo has no published per-token price.

Which scores higher on benchmarks?

There is no independent benchmark that covers both models yet. GPT-5.1 Chat has not been scored yet and Kimi K2 Thinking Turbo has not been scored yet.

Which is better for coding?

There are no published SWE-bench Verified results for GPT-5.1 Chat and Kimi K2 Thinking Turbo yet, so there is no like-for-like coding score. Test both on a sample of your own tasks. Both support tool calling for agent workflows.

Which has the bigger context window?

Kimi K2 Thinking Turbo has the largest context window at 262,144 tokens, against 128,000 for GPT-5.1 Chat. Maximum output per response: GPT-5.1 Chat up to 16,384, Kimi K2 Thinking Turbo up to 262,144 tokens.

Which can read images, PDFs, audio or video?

GPT-5.1 Chat accepts text and images; Kimi K2 Thinking Turbo accepts text. GPT-5.1 Chat handles the widest range of inputs.

Are any of these open source?

Kimi K2 Thinking Turbo publishes its weights and can be self-hosted; GPT-5.1 Chat is proprietary.

Which is newer?

GPT-5.1 Chat is the newest, released Nov 13, 2025. Kimi K2 Thinking Turbo came out Nov 6, 2025. Knowledge cutoff: GPT-5.1 Chat Sep 30, 2024, Kimi K2 Thinking Turbo Aug 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.