OpenAI GPT-4o mini vs OpenAI gpt-oss-120b — side-by-side specs.
OpenAI GPT-4o mini | OpenAI gpt-oss-120b | |
|---|---|---|
| Overview | ||
| Company | OpenAI | OpenAI |
| Release date | Jul 18 2024 | Aug 5 2025 |
| Model type | — | — |
| Open source | No | Yes |
| Specifications | ||
Parameters | — | — |
Context window | — | — |
| Benchmarks | ||
Science reasoning GPQA Diamond | — | — |
Software engineering SWE-Bench Verified | — | — |
Multimodal understanding MMMU | — | — |
| Timeline | ||
| Release gap | GPT-4o mini shipped 383 days before gpt-oss-120b | |
GPT-4o mini and gpt-oss-120b do not have directly comparable benchmark scores published on GPQA Diamond, SWE-Bench Verified, or MMMU. GPT-4o mini shipped 383 days before gpt-oss-120b, so benchmark comparisons should account for the intervening progress.
gpt-oss-120b is an open-source / open-weight model; GPT-4o mini 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.