Compare / head-to-head
gpt-oss-20bvso3
o3 leads 3 of 4 shared benchmarks. o3 has the larger context window (200K tokens).
Benchmarks from cited public sources; pricing from official pages; status from official provider feeds.
Shared benchmarks
0 – 3
o3 leads · 1 tied
Cheaper per token
—
list price, input + output
Larger context
o3
200K tokens
Provider uptime (30d)
94.2446%
OpenAI
gpt-oss-20b
OpenAI · released 2025-08-05
text
- Context
- 131K
- Max out
- 131K
- Input /1M
- —
- Output /1M
- —
- Cached /1M
- —
- Scores
- 6 · 5 core
Quality
Benchmark matrix
4 shared · 1 only gpt-oss-20b · 3 only o3| Benchmark | gpt-oss-20b | o3 | Δ | Edge |
|---|---|---|---|---|
| Reported by both · 4 | ||||
| SWE-bench Verified | 60.7% ↗ | 69.1% ↗ | -8.4 pt | o3 |
| GPQA Diamond | 71.5% ↗ | 81.8% ↗epoch | -10.3 pt | o3 |
| AIME 2025 | 89.2% ↗matharena ⚠ | 89.2% ↗matharena ⚠ | 0 | Tie |
| OTIS Mock AIME 2024-2025 (Epoch AI run) | 65.3% ↗epoch | 84.4% ↗epoch | -19.1 pt | o3 |
| Only gpt-oss-20b reports · 1 | ||||
| LMArena Elo | 1287.3 ↗ | not reported | — | — |
| Only o3 reports · 3 | ||||
| FrontierMath Tiers 1-3 v2 (Epoch AI run) | not reported | 33.3% ↗epoch | — | — |
| SimpleQA Verified | not reported | 49.4% ↗epoch | — | — |
| SWE-bench Verified (Epoch AI run) | not reported | 62.3% ↗epoch | — | — |
Scores tagged "epoch" or "matharena" are independent runs, used only where the lab has not published its own; ⚠ marks rows MathArena flags as released after the competition. Higher is better on every row. Δ is gpt-oss-20b minus o3 in the benchmark's own unit. "Not reported" means the lab has not published that figure; it is not a zero. ↗ opens the source.
Specs & pricing
Side by side
Official pricing pages and model cards| Spec | gpt-oss-20b | o3 | Edge |
|---|---|---|---|
| Context window | 131K tokens | 200K tokens | o3 |
| Max output | 131K tokens | 100K tokens | gpt-oss-20b |
| Input price / 1M | — | $2 ↗ | — |
| Output price / 1M | — | $8 ↗ | — |
| Cached input / 1M | — | $0.5 ↗ | — |
| Input + output / 1M Lower is cheaper. List prices; batch, tool and regional fees excluded. | — | $10 | — |
| Modalities | text | text · vision | o3 |
| Released | 2025-08-05 | 2025-04-16 | — |
| Cited benchmark scores | 6 | 7 | — |
Reliability
OpenAI status
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