Moonshot AI Kimi K1.5 vs OpenAI gpt-oss-20b — side-by-side specs.
Moonshot AI Kimi K1.5 | OpenAI gpt-oss-20b | |
|---|---|---|
| Overview | ||
| Company | Moonshot AI | OpenAI |
| Release date | Jan 20 2025 | Aug 5 2025 |
| Model type | — | — |
| Open source | No | Yes |
| Specifications | ||
Parameters | — | — |
Context window | 128k | — |
| Benchmarks | ||
Science reasoning GPQA Diamond | — | — |
Software engineering SWE-Bench Verified | — | — |
Multimodal understanding MMMU | — | — |
| Timeline | ||
| Release gap | Kimi K1.5 shipped 197 days before gpt-oss-20b | |
Kimi K1.5 and gpt-oss-20b do not have directly comparable benchmark scores published on GPQA Diamond, SWE-Bench Verified, or MMMU. Kimi K1.5 shipped 197 days before gpt-oss-20b, so benchmark comparisons should account for the intervening progress.
gpt-oss-20b is an open-source / open-weight model; Kimi K1.5 is proprietary.
Direct benchmark comparisons are unavailable — at least one of these models has not published scores on GPQA Diamond, SWE-Bench Verified, or MMMU.