Compare / head-to-head
GPT-5.1vsgpt-oss-20b
GPT-5.1 leads 4 of 4 shared benchmarks. GPT-5.1 has the larger context window (400K tokens).
Benchmarks from cited public sources; pricing from official pages; status from official provider feeds.
Shared benchmarks
4 – 0
GPT-5.1 leads
Cheaper per token
—
list price, input + output
Larger context
GPT-5.1
400K tokens
Provider uptime (30d)
95.1952%
OpenAI
GPT-5.1
OpenAI · released 2025-11-13
textvision
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 · 2 only GPT-5.1 · 1 only gpt-oss-20b| Benchmark | GPT-5.1 | gpt-oss-20b | Δ | Edge |
|---|---|---|---|---|
| Reported by both · 4 | ||||
| GPQA Diamond | 87.6% ↗epoch | 71.5% ↗ | +16.1 pt | GPT-5.1 |
| AIME 2025 | 94.2% ↗matharena ⚠ | 89.2% ↗matharena ⚠ | +5 pt | GPT-5.1 |
| LMArena Elo | 1422.6 ↗ | 1287.3 ↗ | +135.3 | GPT-5.1 |
| OTIS Mock AIME 2024-2025 (Epoch AI run) | 88.6% ↗epoch | 65.3% ↗epoch | +23.3 pt | GPT-5.1 |
| Only GPT-5.1 reports · 2 | ||||
| SimpleQA Verified | 48% ↗epoch | not reported | — | — |
| SWE-bench Verified (Epoch AI run) | 68% ↗epoch | not reported | — | — |
| Only gpt-oss-20b reports · 1 | ||||
| SWE-bench Verified | not reported | 60.7% ↗ | — | — |
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-5.1 minus gpt-oss-20b 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-5.1 | gpt-oss-20b | Edge |
|---|---|---|---|
| Context window | 400K tokens | 131K tokens | GPT-5.1 |
| Max output | 128K tokens | 131K tokens | gpt-oss-20b |
| Input price / 1M | $1.25 ↗ | — | — |
| Output price / 1M | $10 ↗ | — | — |
| Cached input / 1M | $0.125 ↗ | — | — |
| Input + output / 1M Lower is cheaper. List prices; batch, tool and regional fees excluded. | $11.25 | — | — |
| Modalities | text · vision | text | GPT-5.1 |
| Released | 2025-11-13 | 2025-08-05 | — |
| Cited benchmark scores | 6 | 6 | — |
Reliability
OpenAI status
Last 60 days · refreshed daily on this page · live on /statusMore matchups
GPT-5.1 vs …
Models sharing the most benchmarksMore matchups
gpt-oss-20b vs …
Models sharing the most benchmarksBuilt by Respan
Which one wins on your data?
Public benchmarks are a starting point. Run GPT-5.1 and gpt-oss-20b on your own prompts with Respan evals, or route to either through one gateway key with automatic failover.