gpt-oss-120b vs OpenAI o3
Benchmarks, API pricing and specs, head to head. Data updated 2026-06-10.
OpenAI · Aug 2025
OpenAI's open-weights MoE reasoning model under Apache 2.0 — near o4-mini quality, runnable on a single 80GB GPU.
OpenAI · Apr 2025
OpenAI's dedicated 2025 reasoning model that pioneered thinking-with-images and agentic tool use within chain-of-thought.
The verdict
OpenAI o3 wins 2 of the 3 benchmarks these models share, against 1 for gpt-oss-120b. On price the gap is dramatic: gpt-oss-120b works out roughly 18x cheaper per blended million tokens. OpenAI o3 also takes 200K of context versus 131K for gpt-oss-120b. And gpt-oss-120b is open-weights (Apache 2.0), so it can be self-hosted — a structural advantage if data control or vendor independence matters.
Benchmark head-to-head 1–2
Specs & pricing
| gpt-oss-120b | OpenAI o3 | |
|---|---|---|
| modhub Index | — | 68.9 |
| Input price / 1M | $0.1 | $2 |
| Output price / 1M | $0.5 | $8 |
| Context window | 131K | 200K |
| Max output | 131K | 100K |
| Open weights | yes (Apache 2.0) | no |
| Reasoning model | yes | yes |
| Multimodal input | text | text, image |
| Knowledge cutoff | Jun 2024 | May 2024 |
| Released | Aug 2025 | Apr 2025 |
| Example monthly cost* | $1.75 | $32.00 |
* 10M input + 1.5M output tokens per month at list prices, no caching. Green = better value on that row.
Frequently asked questions
- Which is better, gpt-oss-120b or OpenAI o3?
- OpenAI o3 wins 2 of the 3 benchmarks these models share, against 1 for gpt-oss-120b. On price the gap is dramatic: gpt-oss-120b works out roughly 18x cheaper per blended million tokens. OpenAI o3 also takes 200K of context versus 131K for gpt-oss-120b. And gpt-oss-120b is open-weights (Apache 2.0), so it can be self-hosted — a structural advantage if data control or vendor independence matters.
- Which is cheaper, gpt-oss-120b or OpenAI o3?
- gpt-oss-120b costs $0.1/$0.5 per million input/output tokens, while OpenAI o3 costs $2/$8. For a typical workload of 10M input and 1.5M output tokens per month, that's $1.75 versus $32.00.
- Which model is better for coding, gpt-oss-120b or OpenAI o3?
- We don't yet track SWE-bench Verified results for both models; check their individual pages for coding-related scores.