GPT-5.1 High vs Kimi K3: Specs & Benchmark Comparison
GPT-5.1 High is developed by OpenAI, while Kimi K3 comes from Moonshot AI. GPT-5.1 High was released in November 2025, and Kimi K3 followed 8 months later in July 2026. Kimi K3 has a published size of about 2.8 trillion parameters; OpenAI has not disclosed the parameter count of GPT-5.1 High.
We have 2 benchmark results for GPT-5.1 High and 3 benchmark results for Kimi K3, but they overlap on a single test: GPQA, where Kimi K3 scores 94.0% against 88.0%.
GPT-5.1 High is the cheaper API at $2 per million input tokens and $8 per million output tokens, about 50% below Kimi K3 at $3 and $15. Kimi K3 takes the larger context window at 1M tokens, compared with 256K for GPT-5.1 High. Both accept text and images as input.
| Characteristic | GPT-5.1 High | Kimi K3 |
|---|---|---|
| Company | OpenAI | Moonshot AI |
| Release Date | November 11, 2025 | July 16, 2026 |
| Parameters | — | 2.8T |
| Multimodal | Yes | Yes |
| Context (input) | 256K | 1.0M |
| Context (output) | 128K | 1.0M |
| Input Price / 1M | $2.00 | $3.00 |
| Output Price / 1M | $8.00 | $15.00 |
| Average Score | 94.0% | 95.7% |
| Benchmarks | ||
| GPQA | 88.0% | 94.0% |
Visual Benchmark Comparison
Verdict
Kimi K3 leads in 2 out of 4 comparison categories.
Both models show comparable average scores: GPT-5.1 High — 0.9, Kimi K3 — 1.0.
GPT-5.1 High is 1.8x cheaper: input $2.00/1M vs $3.00/1M tokens.
Kimi K3 supports a larger context: 1M vs 256K tokens.
Kimi K3 is newer: released 7/16/2026 vs 11/11/2025.
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Frequently Asked Questions
Which is better for coding — GPT-5.1 High or Kimi K3?
Which model is cheaper — GPT-5.1 High or Kimi K3?
Which has a larger context window — GPT-5.1 High or Kimi K3?
The GPT-5.1 High and Kimi K3 comparison is updated for 2026. Data includes benchmark results, API pricing, context window size and other specifications. For more detailed information, visit the GPT-5.1 High or Kimi K3 page. See also the complete list of AI model comparisons.