Model Comparison

GPT-5.4 vs Kimi-k1.5Which is better in 2026?

Comparing GPT-5.4 and Kimi-k1.5 across benchmarks, pricing, and capabilities.

Verdict: GPT-5.4 vs Kimi-k1.5 — which is better?

GPT-5.4 (by OpenAI) and Kimi-k1.5 (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.

Choose GPT-5.4 if…

  • you want the most recent training data — it shipped Mar 2026

Choose Kimi-k1.5 if…

  • you are already invested in the Moonshot AI ecosystem

Performance Benchmarks

Comparative analysis across standard metrics

No common benchmarks found

GPT-5.4 and Kimi-k1.5don't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Arena Performance

Human preference votes

Context Window

Maximum input and output token capacity

Only GPT-5.4 specifies input context (1,000,000 tokens). Only GPT-5.4 specifies output context (128,000 tokens).

OpenAI
GPT-5.4
Input1,000,000 tokens
Output128,000 tokens
Moonshot AI
Kimi-k1.5
Input- tokens
Output- tokens
Wed Jul 15 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both GPT-5.4 and Kimi-k1.5 support multimodal inputs.

They are both capable of processing various types of data, offering versatility in application.

GPT-5.4

Text
Images
Audio
Video

Kimi-k1.5

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-5.4

Proprietary

Closed source

Kimi-k1.5

Proprietary

Closed source

Release Timeline

When each model was launched

GPT-5.4 was released on 2026-03-05, while Kimi-k1.5 was released on 2025-01-20.

GPT-5.4 is 14 months newer than Kimi-k1.5.

GPT-5.4

Mar 5, 2026

4 months ago

1.1yr newer
Kimi-k1.5

Jan 20, 2025

1.5 years ago

Knowledge Cutoff

When training data ends

Neither model specifies a knowledge cutoff date.

Unable to compare the recency of their training data.

No cutoff dates available

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion

Key Takeaways

Larger context window (1,000,000 tokens)

No standout differentiators in the data we have for this pair.

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against GPT-5.4 and Kimi-k1.5 side-by-side, then vote on the output you prefer.

GPT-5.4
✓ Preferred
Kimi-k1.5
Open in Playground
AI Model Comparison Table
Feature
OpenAI
GPT-5.4
Moonshot AI
Kimi-k1.5

FAQ

Common questions about GPT-5.4 vs Kimi-k1.5.

Which is better, GPT-5.4 or Kimi-k1.5?

GPT-5.4 (OpenAI) and Kimi-k1.5 (Moonshot AI) each have strengths in different areas. Compare their benchmark scores, pricing, context windows, and capabilities above to determine which fits your needs.

How does GPT-5.4 compare to Kimi-k1.5 in benchmarks?

GPT-5.4 scores Tau2 Telecom: 98.9%, ARC-AGI: 93.7%, Graphwalks BFS <128k: 93.0%, GPQA: 92.8%, Graphwalks parents <128k: 89.8%. Kimi-k1.5 scores MATH-500: 96.2%, CLUEWSC: 91.4%, C-Eval: 88.3%, MMLU: 87.4%, IFEval: 87.2%.

What are the context window sizes for GPT-5.4 and Kimi-k1.5?

GPT-5.4 supports 1.0M tokens and Kimi-k1.5 supports an unknown number of tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

Who makes GPT-5.4 and Kimi-k1.5?

GPT-5.4 is developed by OpenAI and Kimi-k1.5 is developed by Moonshot AI.