293 models ranked for API and backend development. Function calling and JSON mode are critical for building reliable services. Scored with heavy bonuses for these capabilities.
| # | Model | Score |
|---|---|---|
| 1 | GPT-5.4 ProOpenAI | 91 |
| 2 | GPT-5.2 ProOpenAI | 90 |
| 3 | GPT-5 ProOpenAI | 90 |
| 4 | o3 ProOpenAI | 82 |
| 5 | Claude Opus 4.1Anthropic | 81 |
| 6 | o3 Deep ResearchOpenAI | 74 |
| 7 | Claude Opus 4.6Anthropic | 71 |
| 8 | Claude Opus 4.5Anthropic | 70 |
| 9 | GPT-5.4OpenAI | 70 |
| 10 | o1-proOpenAI | 77 |
| 11 | Claude Sonnet 4.5Anthropic | 69 |
| 12 | Qwen3 VL 30B A3B ThinkingAlibaba | 69 |
| 13 | Qwen3 VL 235B A22B ThinkingAlibaba | 69 |
| 14 | GPT-5.2OpenAI | 68 |
| 15 | Gemini 3.1 Pro Preview Custom ToolsGoogle | 68 |
| 16 | Gemini 3.1 Pro PreviewGoogle | 68 |
| 17 | Gemini 3 Pro PreviewGoogle | 68 |
| 18 | Claude Sonnet 4.6Anthropic | 68 |
| 19 | Claude Opus 4Anthropic | 76 |
| 20 | GPT-5.1OpenAI | 67 |
| 21 | GPT-5.3-CodexOpenAI | 67 |
| 22 | GPT-5.2-CodexOpenAI | 67 |
| 23 | GPT-5OpenAI | 67 |
| 24 | Gemini 3 Flash PreviewGoogle | 66 |
| 25 | o4 Mini Deep ResearchOpenAI | 66 |
| 26 | GPT-5.1-Codex-MaxOpenAI | 66 |
| 27 | Gemini 3.1 Flash Lite PreviewGoogle | 66 |
| 28 | Gemini 2.5 ProGoogle | 66 |
| 29 | Gemini 2.5 Flash Lite Preview 09-2025Google | 65 |
| 30 | GPT-5 MiniOpenAI | 65 |
JSON mode ensures reliable structured output for generating OpenAPI specs, database schemas, and type definitions. Models understand REST, GraphQL, and gRPC patterns.
Generate endpoint handlers, middleware, validation logic, and test suites. Large context windows let models understand your entire service architecture for consistent code.
Function calling models understand tool invocation patterns. They help design and implement API integrations with third-party services, SDKs, and webhooks.
Reasoning models analyze query patterns, identify N+1 problems, suggest caching strategies, and audit endpoints for security vulnerabilities like injection and IDOR.