GPT OSS 20B vs o1-mini
GPT OSS 20B and o1-mini are closely matched at 17.4 and 10.5 on the LLM Stats Score. GPT OSS 20B is 60.0x cheaper per token.
OpenAI · OpenAI · Updated for 2026
Which is better?
GPT OSS 20B and o1-mini are closely matched on the overall LLM Stats Score at 17.4 and 10.5.
In the 2 individual benchmarks reported for both models, GPT OSS 20B wins 2; this is a narrower head-to-head signal than the composite indexes.
On price, GPT OSS 20B is roughly 60.0x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
GPT OSS 20B also accepts a larger context window (131,072 input tokens), making it the stronger choice for long documents and large codebases.
Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.
Choose GPT OSS 20B
- you value its reported benchmark strengths — it wins 2 of 2 exact shared results
- cost matters — it's about 60.0x cheaper per token
- you process long inputs — it offers a 131,072 token context window
- you want the most recent training data — it shipped Aug 2025
- you need open weights you can self-host or fine-tune
Choose o1-mini
- you want predictable pricing at $3.00/M input and $12.00/M output
At a glance
The differences that matter most.
Capability indexes
Additional strengths measured across groups of related public benchmarks
Individual benchmarks
7 reported for GPT OSS 20B · 6 for o1-mini
GPT OSS 20B outperforms in 2 benchmarks (GPQA, MMLU), while o1-mini is better at 0 benchmarks.
GPT OSS 20B significantly outperforms across most benchmarks.
Human preference
Blind head-to-head votes and playground preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, GPT OSS 20B ($0.05/1M tokens) is 60.0x cheaper than o1-mini ($3.00/1M tokens).
For output processing, GPT OSS 20B ($0.20/1M tokens) is 60.0x cheaper than o1-mini ($12.00/1M tokens).
In conclusion, o1-mini is more expensive than GPT OSS 20B.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
GPT OSS 20B accepts 131,072 input tokens compared to o1-mini's 128,000 tokens. o1-mini can generate longer responses up to 65,536 tokens, while GPT OSS 20B is limited to 32,768 tokens.
License
Usage and distribution terms
GPT OSS 20B is licensed under Apache 2.0, while o1-mini uses a proprietary license.
License differences may affect how you can use these models in commercial or open-source projects.
Apache 2.0
Open weights
Proprietary
Closed source
Release Timeline
When each model was launched
GPT OSS 20B was released on 2025-08-05, while o1-mini was released on 2024-09-12.
GPT OSS 20B is 11 months newer than o1-mini.
Aug 5, 2025
1.1 years ago
10mo newerSep 12, 2024
2.0 years ago
Knowledge Cutoff
When training data ends
Neither model specifies a knowledge cutoff date.
Unable to compare the recency of their training data.
Provider Availability
GPT OSS 20B is available from Novita, Fireworks, Groq, OpenAI. o1-mini is available from OpenAI, Azure.
GPT OSS 20B
o1-mini
Outputs Comparison
Judge for yourself.
Run your own prompts against GPT OSS 20B and o1-mini side-by-side, then vote on the output you prefer.
FAQ
Common questions about GPT OSS 20B vs o1-mini.