gpt-oss-20b vs Kimi K2.5
How do these models stack up? Below is an expert side-by-side comparison of specifications, context window capacity, live pricing per million tokens, and standardized benchmark scores for gpt-oss-20b and Kimi K2.5.
gpt-oss-20b
gpt-oss-20b is an open-weight 21B parameter model released by OpenAI under the Apache 2.0 license. It uses a Mixture-of-Experts (MoE) architecture with 3.6B active parameters per forward pass, optimized for...
Kimi K2.5
Kimi K2.5 is Moonshot AI's native multimodal model, delivering state-of-the-art visual coding capability and a self-directed agent swarm paradigm. Built on Kimi K2 with continued pretraining over approximately 15T mixed...
Technical Specifications
| Specification | gpt-oss-20b | Kimi K2.5 |
|---|---|---|
| Provider | OpenAI | Moonshot AI |
| Context Window | 131,072 tokens | 262,144 tokens |
| Agent Suitability | N/A | N/A |
| Time to First Token (TTFT) | N/A | N/A |
| Deployment Model | managed api | managed api |
| Production Stability | stable | stable |
| API Available | Yes | Yes |
| Released Date | 2025-08-05 | 2026-01-27 |
API Pricing Comparison
Input Price per Million Tokens
gpt-oss-20b
$0.03
Kimi K2.5
$0.38
Output Price per Million Tokens
gpt-oss-20b
$0.14
Kimi K2.5
$2.02
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Benchmark Performance Metrics
Scores show the raw performance percentages verified across key evaluation suites. Higher bars indicate superior accuracy and capability in that domain.
gpt-oss-20b Quirks & Gotchas
No developer gotchas reported.
Kimi K2.5 Quirks & Gotchas
No developer gotchas reported.