Together AI· Inference platform

Kimi K3 vs GPT-5.6 Sol on DeepSWE: Cost, Coding, and Routing

Summary GPT-5.6 Sol edges Kimi K3 on single-shot quality, but Kimi wins on pass@k with k > 1 and costs 64% less per completed task. The two models succeed and fail in different ways, which makes routing between them the strongest play on the benchmark. Kimi K3 vs GPT-5.6 Sol is close on DeepSWE pass@1: Sol leads 72.7% to 68.5%, a 4.2 point gap. Give the models more attempts and Kimi K3 pulls ahead. It wins pass@2 (82.0 vs 81.0) and pass@4 (89.4% vs 85.8%). Kimi K3 is far cheaper: \$4.65 per rollout vs \$8.37, and 2.8x more solved tasks per dollar. GPT-5.6 Sol is the more reliable model: it solves more tasks on all 4/4 tries (61 vs 45). The models diverge (0.46 correlation across which tasks they solve correctly and incorrectly) and fail differently, so a Kimi-first cascade that escalates to Sol covers 108 of 113 tasks and reaches about 85.6%. Available now Run Kimi K3 on Together AI Full 1M context, automatic prefix caching, OpenAI-compatible API, served from US infrastructure. Open the playground DeepSWE · Head to Head Kimi K3 vs GPT-5.6 Sol at a glance Metric Kimi K3 GPT-5.6 Sol DeepSWE pass@1 68.5% 72.7% DeepSWE pass@2 82.0% 81.0% DeepSWE pass@4 89.4% 85.8% …

Announced

26 Jul 2026 00:00 UTC