Side-by-side comparison of pricing, 12 benchmarks, and generation speed.
| Metric | Gemini 2.5 Flash Preview (Sep '25) (Reasoning) | gpt-oss-20B (high) |
|---|---|---|
| Input ($/M tokens) | $0 | $0.05 |
| Output ($/M tokens) | $0 | $0.2 |
Data from Artificial Analysis API — 12 benchmarks
Gemini 2.5 Flash Preview (Sep '25) (Reasoning) is cheaper overall. Its blended price (3:1 input/output ratio) is $0.00/M tokens vs $0.09/M for gpt-oss-20B (high).
Gemini 2.5 Flash Preview (Sep '25) (Reasoning) wins 7 out of 12 benchmarks compared to 4 for gpt-oss-20B (high). See the detailed benchmark chart above for per-category results.
gpt-oss-20B (high) generates tokens faster at 256 tok/s vs 0 tok/s. Gemini 2.5 Flash Preview (Sep '25) (Reasoning) also has lower time-to-first-token (0.00s vs 0.34s).
Choose based on your priorities: Gemini 2.5 Flash Preview (Sep '25) (Reasoning) for lower cost, Gemini 2.5 Flash Preview (Sep '25) (Reasoning) for stronger benchmark performance, and gpt-oss-20B (high) for faster generation. For latency-sensitive apps, check the TTFT comparison above.