ChatGPT-4o (March 2025) vs GPT OSS 20B

Compare ChatGPT-4o (March 2025) and GPT OSS 20B, both from OpenAI, in 3 community votes, gpt oss 20b wins 67% of head-to-head duels, context windows of 128K vs 131K, tested across 32 shared challenges. Updated February 2026.

In 3 community votes, GPT OSS 20B wins 67% of head-to-head duels. GPT OSS 20B leads in Reasoning. Based on blind community voting from the RIVAL open dataset of 3+ human preference judgments for this pair.

Reasoning: GPT OSS 20B wins 100% of votes
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