gpt-oss-20b vs OpenAI o4-mini

Benchmarks, API pricing and specs, head to head. Data updated 2026-06-10.

gpt-oss-20b

OpenAI · Aug 2025

The small gpt-oss variant that runs on a 16GB consumer GPU or laptop — local reasoning for everyone, Apache 2.0 licensed.

OpenAI o4-mini

OpenAI · Apr 2025

80.9

A compact reasoning model that punched far above its price on math — 92.7% on AIME 2025 at $1.10 per million input tokens.

The verdict

These two models don't yet share verified results on the benchmarks we track, so judge them on specs, pricing and intended use. On price the gap is dramatic: gpt-oss-20b works out roughly 22x cheaper per blended million tokens. OpenAI o4-mini also takes 200K of context versus 131K for gpt-oss-20b. And gpt-oss-20b is open-weights (Apache 2.0), so it can be self-hosted — a structural advantage if data control or vendor independence matters.

Specs & pricing

gpt-oss-20bOpenAI o4-mini
modhub Index80.9
Input price / 1M$0.05$1.1
Output price / 1M$0.2$4.4
Context window131K200K
Max output131K100K
Open weightsyes (Apache 2.0)no
Reasoning modelyesyes
Multimodal inputtexttext, image
Knowledge cutoffJun 2024May 2024
ReleasedAug 2025Apr 2025
Example monthly cost*$0.8$17.60

* 10M input + 1.5M output tokens per month at list prices, no caching. Green = better value on that row.

Frequently asked questions

Which is better, gpt-oss-20b or OpenAI o4-mini?
These two models don't yet share verified results on the benchmarks we track, so judge them on specs, pricing and intended use. On price the gap is dramatic: gpt-oss-20b works out roughly 22x cheaper per blended million tokens. OpenAI o4-mini also takes 200K of context versus 131K for gpt-oss-20b. And gpt-oss-20b is open-weights (Apache 2.0), so it can be self-hosted — a structural advantage if data control or vendor independence matters.
Which is cheaper, gpt-oss-20b or OpenAI o4-mini?
gpt-oss-20b costs $0.05/$0.2 per million input/output tokens, while OpenAI o4-mini costs $1.1/$4.4. For a typical workload of 10M input and 1.5M output tokens per month, that's $0.8 versus $17.60.
Which model is better for coding, gpt-oss-20b or OpenAI o4-mini?
We don't yet track SWE-bench Verified results for both models; check their individual pages for coding-related scores.

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