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Model Comparison

GPT-5 vs Kimi K2 0905Which is better in 2026?

Both models are evenly matched across the benchmarks. Kimi K2 0905 is 3.2x cheaper per token.

Verdict: GPT-5 vs Kimi K2 0905 — which is better?

GPT-5 (by OpenAI) and Kimi K2 0905 (by Moonshot AI) are two of the AI models people compare most. Here is how they stack up on benchmarks, price and capabilities, and which one to pick in 2026.

GPT-5 outperforms in 2 benchmarks (GPQA, MMLU), while Kimi K2 0905 is better at 2 benchmarks (HumanEval, MATH). Both models are evenly matched across the benchmarks.

On price, Kimi K2 0905 is roughly 3.2x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

GPT-5 also accepts a larger context window (400,000 input tokens), making it the stronger choice for long documents and large codebases.

Choose GPT-5 if…

  • you process long inputs — it offers a 400,000 token context window

Choose Kimi K2 0905 if…

  • cost matters — it's about 3.2x cheaper per token
  • you want the most recent training data — it shipped Sep 2025

Performance Benchmarks

Comparative analysis across standard metrics

4 benchmarks

GPT-5 outperforms in 2 benchmarks (GPQA, MMLU), while Kimi K2 0905 is better at 2 benchmarks (HumanEval, MATH).

Both models are evenly matched across the benchmarks.

Fri Aug 07 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

Kimi K2 0905 costs less

For input processing, GPT-5 ($1.25/1M tokens) is 2.1x more expensive than Kimi K2 0905 ($0.60/1M tokens).

For output processing, GPT-5 ($10.00/1M tokens) is 4.0x more expensive than Kimi K2 0905 ($2.50/1M tokens).

In conclusion, GPT-5 is more expensive than Kimi K2 0905.*

* Using a 3:1 ratio of input to output tokens

Lowest available price from all providers
Fri Aug 07 2026 • llm-stats.com
OpenAI
GPT-5
Input tokens$1.25
Output tokens$10.00
Best providerOpenAI
Moonshot AI
Kimi K2 0905
Input tokens$0.60
Output tokens$2.50
Best providerNovita
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

GPT-5 accepts 400,000 input tokens compared to Kimi K2 0905's 262,144 tokens. Kimi K2 0905 can generate longer responses up to 262,144 tokens, while GPT-5 is limited to 128,000 tokens.

OpenAI
GPT-5
Input400,000 tokens
Output128,000 tokens
Moonshot AI
Kimi K2 0905
Input262,144 tokens
Output262,144 tokens
Fri Aug 07 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

GPT-5 supports multimodal inputs, whereas Kimi K2 0905 does not.

GPT-5 can handle both text and other forms of data like images, making it suitable for multimodal applications.

GPT-5

Text
Images
Audio
Video

Kimi K2 0905

Text
Images
Audio
Video

License

Usage and distribution terms

Both models are licensed under proprietary licenses.

Both models have usage restrictions defined by their respective organizations.

GPT-5

Proprietary

Closed source

Kimi K2 0905

Proprietary

Closed source

Release Timeline

When each model was launched

GPT-5 was released on 2025-08-07, while Kimi K2 0905 was released on 2025-09-05.

Kimi K2 0905 is 1 month newer than GPT-5.

GPT-5

Aug 7, 2025

1.0 years ago

Kimi K2 0905

Sep 5, 2025

11 months ago

4w newer

Knowledge Cutoff

When training data ends

GPT-5 has a documented knowledge cutoff of 2024-09-30, while Kimi K2 0905's cutoff date is not specified.

We can confirm GPT-5's training data extends to 2024-09-30, but cannot make a direct comparison without Kimi K2 0905's cutoff date.

GPT-5

Sep 2024

Kimi K2 0905

—

Provider Availability

GPT-5 is available from OpenAI. Kimi K2 0905 is available from Novita.

GPT-5

openai logo
OpenAI
Input Price:Input: $1.25/1MOutput Price:Output: $10.00/1M

Kimi K2 0905

novita logo
Novita
Input Price:Input: $0.60/1MOutput Price:Output: $2.50/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

OpenAI
Larger context window (400,000 tokens)
Supports multimodal inputs
Higher GPQA score (85.7% vs 75.8%)
Higher MMLU score (92.5% vs 90.2%)
Moonshot AI
Less expensive input tokens
Less expensive output tokens
Higher HumanEval score (94.5% vs 93.4%)
Higher MATH score (89.1% vs 84.7%)

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against GPT-5 and Kimi K2 0905 side-by-side, then vote on the output you prefer.

GPT-5
✓ Preferred
Kimi K2 0905
Open in Playground
AI Model Comparison Table
Feature
OpenAI
GPT-5
Moonshot AI
Kimi K2 0905

FAQ

Common questions about GPT-5 vs Kimi K2 0905.

Which is better, GPT-5 or Kimi K2 0905?

Both models are evenly matched across the benchmarks. GPT-5 is made by OpenAI and Kimi K2 0905 is made by Moonshot AI. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does GPT-5 compare to Kimi K2 0905 in benchmarks?

GPT-5 scores SWE-Lancer (IC-Diamond subset): 100.0%, COLLIE: 99.0%, Tau2 Telecom: 96.7%, OpenAI-MRCR: 2 needle 128k: 95.2%, AIME 2025: 94.6%. Kimi K2 0905 scores HumanEval: 94.5%, MMLU: 90.2%, MATH: 89.1%, MMLU-Pro: 82.5%, GPQA: 75.8%.

Is GPT-5 cheaper than Kimi K2 0905?

Kimi K2 0905 is 2.1x cheaper for input tokens. GPT-5 costs $1.25/M input and $10.00/M output via openai. Kimi K2 0905 costs $0.60/M input and $2.50/M output via novita.

What are the context window sizes for GPT-5 and Kimi K2 0905?

GPT-5 supports 400K tokens and Kimi K2 0905 supports 262K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between GPT-5 and Kimi K2 0905?

Key differences include context window (400K vs 262K), input pricing ($1.25 vs $0.60/M), multimodal support (yes vs no). See the full comparison above for benchmark-by-benchmark results.

Who makes GPT-5 and Kimi K2 0905?

GPT-5 is developed by OpenAI and Kimi K2 0905 is developed by Moonshot AI.

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