Code · best for
Best AI model for Bug Fixing (2026)
Diagnosing root cause and producing a working patch. Ranked from 346 live models on the OpenRouter catalog, weighted for reasoning quality, tool calling, context window.
| # | Model | Score | In / 1M | Out / 1M | Context | |
|---|---|---|---|---|---|---|
| 1 | Qwen: Qwen3.6 Plusqwen/qwen3.6-plus | 136 | $0.33 | $1.95 | 1,000,000 | Try → |
| 2 | xAI: Grok 4.20x-ai/grok-4.20 | 136 | $2.00 | $6.00 | 2,000,000 | Try → |
| 3 | OpenAI: GPT-5.4 Nanoopenai/gpt-5.4-nano | 136 | $0.20 | $1.25 | 400,000 | Try → |
| 4 | OpenAI: GPT-5.4 Miniopenai/gpt-5.4-mini | 136 | $0.75 | $4.50 | 400,000 | Try → |
| 5 | OpenAI: GPT-5.4openai/gpt-5.4 | 136 | $2.50 | $15.00 | 1,050,000 | Try → |
| 6 | Google: Gemini 3.1 Flash Lite Previewgoogle/gemini-3.1-flash-lite-preview | 136 | $0.25 | $1.50 | 1,048,576 | Try → |
| 7 | Qwen: Qwen3.5-Flashqwen/qwen3.5-flash-02-23 | 136 | $0.07 | $0.26 | 1,000,000 | Try → |
| 8 | Google: Gemini 3.1 Pro Preview Custom Toolsgoogle/gemini-3.1-pro-preview-customtools | 136 | $2.00 | $12.00 | 1,048,576 | Try → |
| 9 | OpenAI: GPT-5.3-Codexopenai/gpt-5.3-codex | 136 | $1.75 | $14.00 | 400,000 | Try → |
| 10 | Google: Gemini 3.1 Pro Previewgoogle/gemini-3.1-pro-preview | 136 | $2.00 | $12.00 | 1,048,576 | Try → |
| 11 | Qwen: Qwen3.5 Plus 2026-02-15qwen/qwen3.5-plus-02-15 | 136 | $0.26 | $1.56 | 1,000,000 | Try → |
| 12 | Google: Gemini 3 Flash Previewgoogle/gemini-3-flash-preview | 136 | $0.50 | $3.00 | 1,048,576 | Try → |
| 13 | OpenAI: GPT-5.2openai/gpt-5.2 | 136 | $1.75 | $14.00 | 400,000 | Try → |
| 14 | Amazon: Nova 2 Liteamazon/nova-2-lite-v1 | 136 | $0.30 | $2.50 | 1,000,000 | Try → |
| 15 | xAI: Grok 4.1 Fastx-ai/grok-4.1-fast | 136 | $0.20 | $0.50 | 2,000,000 | Try → |
How we ranked these
For Bug Fixing, we weight models on reasoning quality, tool calling, context window. Higher means better. Scores combine OpenRouter's model metadata (context length, modality support, tool calling, structured output, reasoning capability) with public pricing. See full methodology →
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