ZMIME
Comparison · 3 models · Updated Oct 4, 2026

GPT-5 Mini vs Qwen3.5 Plus vs Kimi K2 Thinking

Too close to call on our weighted score (Qwen3.5 Plus 66, GPT-5 Mini 65, Kimi K2 Thinking 58). The right pick depends on what you value most.

  1. OpenAI

    GPT-5 Mini

    Released Aug 7, 2025

    65/100
    • ECI145.5
    • Price$0.25 / $2.00
    • Context400K
  2. Alibaba (Qwen)

    Qwen3.5 Plus

    Released Feb 16, 2026

    66/100
    • ECI146.8
    • Price$0.40 / $2.40
    • Context1M
  3. Moonshot AI

    Kimi K2 Thinking

    Released Nov 6, 2025

    58/100
    • ECI146.0
    • Price$0.60 / $2.50
    • Context262K
01 — Verdict

Too close to call

It is close. Our weighted score puts them within 1 points (Qwen3.5 Plus 66/100, GPT-5 Mini 65/100, Kimi K2 Thinking 58/100), so choose by what matters most for your work: Qwen3.5 Plus for raw capability and GPT-5 Mini on price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

  • CapabilityQwen3.5 PlusCapabilities Index (ECI): Qwen3.5 Plus 146.8 · Kimi K2 Thinking 146.0 · GPT-5 Mini 145.5
  • Lowest priceGPT-5 MiniGPT-5 Mini $0.688 · Qwen3.5 Plus $0.90 · Kimi K2 Thinking $1.07 per 1M tokens (3:1 blend)
  • Longest contextQwen3.5 PlusQwen3.5 Plus 1,000,000 · GPT-5 Mini 400,000 · Kimi K2 Thinking 262,144 tokens
  • Widest inputsQwen3.5 PlusGPT-5 Mini: Text, Images · Qwen3.5 Plus: Text, Images, Video · Kimi K2 Thinking: Text
  • Self-hostingKimi K2 ThinkingPublishes downloadable weights
How the score is built
MeasureWeightGPT-5 MiniQwen3.5 PlusKimi K2 Thinking
CapabilityCapabilities Index (ECI)50%727473
Price25%585248
Inputs & features15%707035
Context window10%446037
Overall100%65/10066/10058/100
02 — Side by side

Every spec in one table

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

GPT-5 Mini vs Qwen3.5 Plus vs Kimi K2 Thinking specifications side by side
SpecificationGPT-5 MiniOpenAIQwen3.5 PlusAlibaba (Qwen)Kimi K2 ThinkingMoonshot AI
Capability
Capabilities Index (ECI)145.5146.8 (best)146.0
ECI rank#77 of 148#65 of 148 (best)#72 of 148
GPQA DiamondGraduate-level science questions75.0%84.9% (best)84.2%
FrontierMath Tiers 1–3Research-level mathematics46.7%——
OTIS Mock AIME 2024–2025Competition mathematics86.7% (best)86.7% (best)83.1%
SWE-bench VerifiedFixing real GitHub issues64.7%——
SimpleQA VerifiedShort factual questions21.6%25.4% (best)—
Price per million tokens
Input$0.25 (best)$0.40$0.60
Output$2.00 (best)$2.40$2.50
Cached input$0.025——
Blended (3:1)$0.688 (best)$0.90$1.07
Long-context rateSame rateSame rateSame rate
Price sourceOfficial OpenAI APIOfficial Alibaba APIMedian of 10 providers
Limits
Context window400,000 tokens1,000,000 tokens (best)262,144 tokens
Max output128,000 tokens65,536 tokens262,144 tokens (best)
Inputs and features
TextYesYesYes
ImagesYesYesNo
PDFsNoNoNo
AudioNoNoNo
VideoNoYesNo
ReasoningYesminimal · low · medium · highYesYes
Tool callingYesYesYes
Structured outputYesNoNo
Availability
WeightsProprietaryProprietaryOpen
API model IDgpt-5-miniqwen3.5-plus—
API providers23 (best)1010
ReleasedAug 7, 2025Feb 16, 2026Nov 6, 2025
Knowledge cutoffMay 30, 2024Apr 2025Aug 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 Mini$6.50
  • Qwen3.5 Plus$8.80
  • Kimi K2 Thinking$11.00
04 — Questions

Which should you choose?

Which is better: GPT-5 Mini, Qwen3.5 Plus or Kimi K2 Thinking?

It is close. Our weighted score puts them within 1 points (Qwen3.5 Plus 66/100, GPT-5 Mini 65/100, Kimi K2 Thinking 58/100), so choose by what matters most for your work: Qwen3.5 Plus for raw capability and GPT-5 Mini on price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

Which is cheaper, GPT-5 Mini, Qwen3.5 Plus or Kimi K2 Thinking?

GPT-5 Mini is cheaper at $0.25 input / $2.00 output per million tokens (official OpenAI API price). Qwen3.5 Plus costs $0.40 input / $2.40 output per million tokens (official Alibaba API price); Kimi K2 Thinking costs $0.60 input / $2.50 output per million tokens (median across 10 API providers). At a typical mix of three input tokens to one output token, that is $0.688 per million tokens for GPT-5 Mini versus $0.90 for Qwen3.5 Plus (1.3× as much) and $1.07 for Kimi K2 Thinking (1.6× as much).

Which scores higher on benchmarks?

Qwen3.5 Plus scores higher on the Capabilities Index (ECI): Qwen3.5 Plus 146.8 (#65 of 148), Kimi K2 Thinking 146.0 (#72 of 148) and GPT-5 Mini 145.5 (#77 of 148). The confidence ranges of the top two overlap (144.6–148.1 vs 143.4–147.6), so treat the gap as small. On individual benchmarks: GPQA Diamond — Qwen3.5 Plus 84.9%, Kimi K2 Thinking 84.2%, GPT-5 Mini 75.0%; OTIS Mock AIME 2024–2025 — GPT-5 Mini 86.7%, Qwen3.5 Plus 86.7%, Kimi K2 Thinking 83.1%.

Which is better for coding?

There are no published SWE-bench Verified results for Qwen3.5 Plus and Kimi K2 Thinking yet, so there is no like-for-like coding score. On overall capability, Qwen3.5 Plus 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?

Qwen3.5 Plus has the largest context window at 1,000,000 tokens, against 400,000 for GPT-5 Mini and 262,144 for Kimi K2 Thinking. Maximum output per response: GPT-5 Mini up to 128,000, Qwen3.5 Plus up to 65,536, Kimi K2 Thinking up to 262,144 tokens.

Which can read images, PDFs, audio or video?

GPT-5 Mini accepts text and images; Qwen3.5 Plus accepts text, images and video; Kimi K2 Thinking accepts text. Qwen3.5 Plus handles the widest range of inputs.

Are any of these open source?

Kimi K2 Thinking publishes its weights and can be self-hosted; GPT-5 Mini and Qwen3.5 Plus is proprietary.

Which is newer?

Qwen3.5 Plus is the newest, released Feb 16, 2026. Kimi K2 Thinking came out Nov 6, 2025; GPT-5 Mini came out Aug 7, 2025. Knowledge cutoff: GPT-5 Mini May 30, 2024, Qwen3.5 Plus Apr 2025, Kimi K2 Thinking 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.