AI Model Release Tracker - Timeline of Major AI Models from 2022-2026

Composer 2.5 vs gpt-oss-20b

Cursor
Composer 2.5
OpenAI
gpt-oss-20b
Overview
CompanyCursorOpenAI
Release dateMay 18 2026Aug 5 2025
AccessProprietaryOpen Weight
Benchmarks
Multilingual coding
SWE-Bench Multilingual
79.8%
Agentic coding
CursorBench v3.1
63.2%
Next.js coding
Next.js Evals
92%
Agentic terminal coding
Terminal-Bench 2.0
69.3%
Timeline
Release gapgpt-oss-20b shipped 286 days before Composer 2.5

Which is better: Composer 2.5 or gpt-oss-20b?

Composer 2.5 and gpt-oss-20b don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. gpt-oss-20b shipped 286 days before Composer 2.5, so benchmark comparisons should account for the intervening progress.

Composer 2.5 is proprietary, while gpt-oss-20b is open weight.

Direct benchmark comparisons are unavailable — Composer 2.5 and gpt-oss-20b don't publish scores on any of the same benchmarks.

Frequently asked questions

Composer 2.5 was released by Cursor on May 18 2026.

gpt-oss-20b was released by OpenAI on Aug 5 2025.

Composer 2.5 is a proprietary model released by Cursor. gpt-oss-20b is an open weight model released by OpenAI.

Other comparisons