It's May 2026 and there are a lot of coding models to choose from. Everything below is based on my personal experience running them in real agent loops - Claude Code, Copilot, and OpenCode, backed up by benchmark data and what other people are actually saying on Reddit. Quick comparison Benchmark column uses SWE-bench Verified, vendor-reported single-attempt numbers. LMSYS Arena ranks from arena.ai/leaderboard . Model Released Context $/M in $/M out SWE-bench Verified LMSYS rank Open weights Claude Opus 4.7 Apr 2026 1M $5 $25 87.6% #1 (thinking) No GPT-5.5 Apr 2026 1M $5 $30 88.7% #7 (high) No Claude Opus 4.6 Late 2025 1M $5 $25 80.8% #3 (thinking) No Gemini 3.1 Pro Feb 2026 1M $2-$4.00 $12-$18 80.6% #4 No Kimi K2.6 Apr 2026 256K $0.16 $4.00 80.2% #28 Yes Claude Sonnet 4.6 Feb 2026 1M $3 $15 79.6% #23 No DeepSeek V4-Flash Apr 2026 1M $0.14 $0.28 ~79% #24 No Gemini 3 Flash (high) Dec 2025 1M - - 78.0% - No Grok 4.3 2026 1M $1.25 $2.50 ~73% #34 No GPT-5.4 Mar 2026 1M $2.50 $15 - #11 (high) No GPT-5.4 Mini Mar…