Mistral Small 3.2 vs GPT OSS 20B
GPT OSS 20B comes out ahead, 64 to 60 on our weighted score, and it is the cheaper option too.
Mistral AI
Mistral Small 3.2
60/100- ECI131.7
- Price$0.10 / $0.30
- Context128K
- Our pick
OpenAI
GPT OSS 20B
64/100- ECI137.8
- Price$0.07 / $0.295
- Context131K
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GPT OSS 20B is our pick
GPT OSS 20B is the better all-round choice, scoring 64/100 against Mistral Small 3.2 (60). It leads on capability and price. Mistral Small 3.2 wins on inputs & features. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.
- CapabilityGPT OSS 20BCapabilities Index (ECI): GPT OSS 20B 137.8 · Mistral Small 3.2 131.7
- Lowest priceGPT OSS 20BGPT OSS 20B $0.126 · Mistral Small 3.2 $0.15 per 1M tokens (3:1 blend)
- Longest contextGPT OSS 20BGPT OSS 20B 131,072 · Mistral Small 3.2 128,000 tokens
- Widest inputsMistral Small 3.2Mistral Small 3.2: Text, Images · GPT OSS 20B: Text
- Self-hostingAll open weightsEvery model here can be downloaded and run on your own hardware
| Measure | Weight | Mistral Small 3.2 | GPT OSS 20B |
|---|---|---|---|
| CapabilityCapabilities Index (ECI) | 50% | 55 | 63 |
| Price | 25% | 89 | 92 |
| Inputs & features | 15% | 50 | 45 |
| Context window | 10% | 24 | 24 |
| Overall | 100% | 60/100 | 64/100 |
Every spec in one table
Highlighted cells lead their row. Dashes mean the data is not published.
| Specification | ||
|---|---|---|
| Capability | ||
| Capabilities Index (ECI) | 131.7 | 137.8 (best) |
| ECI rank | #123 of 148 | #108 of 148 (best) |
| GPQA DiamondGraduate-level science questions | 49.1% | 60.8% (best) |
| OTIS Mock AIME 2024–2025Competition mathematics | 30.3% | 65.3% (best) |
| Price per million tokens | ||
| Input | $0.10 | $0.07 (best) |
| Output | $0.30 | $0.295 (best) |
| Cached input | — | — |
| Blended (3:1) | $0.15 | $0.126 (best) |
| Long-context rate | Same rate | Same rate |
| Price source | Official Mistral API | Median of 18 providers |
| Limits | ||
| Context window | 128,000 tokens | 131,072 tokens (best) |
| Max output | 16,384 tokens | 32,768 tokens (best) |
| Inputs and features | ||
| Text | Yes | Yes |
| Images | Yes | No |
| PDFs | No | No |
| Audio | No | No |
| Video | No | No |
| Reasoning | No | Yes |
| Tool calling | Yes | Yes |
| Structured output | No | Yes |
| Availability | ||
| Weights | Open | Open |
| API model ID | mistral-small-2506 | — |
| API providers | 6 | 19 (best) |
| Released | Jun 20, 2025 | Aug 5, 2025 |
| Knowledge cutoff | Mar 2025 | — |
What would a month cost?
Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.
Mistral Small 3.2$1.60
GPT OSS 20B$1.29
Which should you choose?
Which is better: Mistral Small 3.2 or GPT OSS 20B?
GPT OSS 20B is the better all-round choice, scoring 64/100 against Mistral Small 3.2 (60). It leads on capability and price. Mistral Small 3.2 wins on inputs & features. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.
Which is cheaper, Mistral Small 3.2 or GPT OSS 20B?
GPT OSS 20B is cheaper at $0.07 input / $0.295 output per million tokens (median across 18 API providers). Mistral Small 3.2 costs $0.10 input / $0.30 output per million tokens (official Mistral API price). At a typical mix of three input tokens to one output token, that is $0.126 per million tokens for GPT OSS 20B versus $0.15 for Mistral Small 3.2 (1.2× as much).
Which scores higher on benchmarks?
GPT OSS 20B scores higher on the Capabilities Index (ECI): GPT OSS 20B 137.8 (#108 of 148) and Mistral Small 3.2 131.7 (#123 of 148). The confidence ranges of the top two overlap (133.0–139.6 vs 126.6–133.9), so treat the gap as small. On individual benchmarks: GPQA Diamond — GPT OSS 20B 60.8%, Mistral Small 3.2 49.1%; OTIS Mock AIME 2024–2025 — GPT OSS 20B 65.3%, Mistral Small 3.2 30.3%.
Which is better for coding?
There are no published SWE-bench Verified results for Mistral Small 3.2 and GPT OSS 20B yet, so there is no like-for-like coding score. On overall capability, GPT OSS 20B leads, which tends to carry over to coding, but test on your own codebase. Both support tool calling for agent workflows.
Which has the bigger context window?
GPT OSS 20B has the largest context window at 131,072 tokens, against 128,000 for Mistral Small 3.2. Maximum output per response: Mistral Small 3.2 up to 16,384, GPT OSS 20B up to 32,768 tokens.
Which can read images, PDFs, audio or video?
Mistral Small 3.2 accepts text and images; GPT OSS 20B accepts text. Mistral Small 3.2 handles the widest range of inputs.
Are any of these open source?
Yes, both publish their weights, so you can self-host them.
Which is newer?
GPT OSS 20B is the newest, released Aug 5, 2025. Mistral Small 3.2 came out Jun 20, 2025. Knowledge cutoff: Mistral Small 3.2 Mar 2025.
How do you decide the winner?
Each model gets a 0–100 score on capability (50%, independent benchmark results); price (25%, blended price per million tokens (3 input : 1 output), log scale); inputs & features (15%, image, PDF, audio and video input, tool calling, structured output and reasoning); context window (10%, maximum tokens per request, log scale). Dimensions missing for any model are dropped and the remaining weights rescaled, so every model is judged on the same evidence. Specs and prices come from public model listings and the labs’ own API pages; capability scores come from independent benchmark runs. Data updated Oct 4, 2026.