Cursor Ships Composer 2.5, Matches Opus 4.7 and GPT-5.5 While Cutting Inference Costs

Cursor has deployed Composer 2.5 inside its product as of May 18, 2026. Built on Moonshot’s open-source Kimi K2.5, the model posts parity with Opus 4.7 and GPT-5.5 on key benchmarks while offering substantially lower token pricing and per-task costs.

Cursor has released Composer 2.5 into production inside its product, a move the company says makes the in-house coding model available to developers and teams for real workflows as of May 18, 2026. The release matters because Cursor reports that Composer 2.5 matches leading models on multiple benchmarks while running on Cursor’s own stack, and it is priced to reduce inference costs for coding tasks.

Composer 2.5 is built on the open-source Kimi K2.5 checkpoint from Moonshot and represents a material training step up from Cursor’s prior Composer 2. Cursor says it trained Composer 2.5 with 25× more synthetic tasks than the previous version and allocated 85% of the model’s compute budget to additional training and reinforcement learning to boost coding performance. On standard tests, Cursor reports Composer 2.5 scored 79.8% on SWE-Bench Multilingual and 63.2% on CursorBench v3.1. Those results are presented as parity with Opus 4.7 and GPT-5.5 on the same benchmarks, preserving competitive accuracy while running on Cursor’s in-house stack.

Cursor is positioning Composer 2.5 as a lower — cost alternative to larger vendors. The company lists a base variant at $0.50 per million input tokens and $2.50 per million output tokens, and a faster variant — reportedly with similar performance — at $3.00 per million input and $15.00 per million output. Cursor says those prices translate to under $1 per task on CursorBench, compared with up to $11 per task for competing models.

Looking ahead, Cursor says it is already training a much larger successor model from scratch in collaboration with SpaceX and xAI, using ten times the compute on the Colossus-2 cluster and a footprint the company describes as equivalent to one million H100 GPUs. The report also notes that SpaceX previously announced plans to acquire Cursor for $60 billion. For builders, Cursor points to model documentation with rollout details and performance notes to help teams evaluate Composer 2.5 and its cost-performance trade — offs.