# AI tools for “API prototyping”

1,786 matching tools; showing 24, ranked by relevance.

Related categories: [ai-api](https://openaitools.app/category/ai-api.md)

| # | Tool Name | Monthly Visits | MoM Growth Rate | Pricing Model | Summary | Why it matched | Profile (Markdown) |
| :--- | :--- | :--- | :--- | :--- | :--- | :--- | :--- |
| 1 | [Google AI Studio](https://openaitools.app/tool/google-ai-studio) | 112,620,020 | +2% | Freemium | Google's rapid prototyping IDE and developer API workbench for building multimodal applications with Gemini models. | category: ai-api; keywords 100%; semantic match | [.md](https://openaitools.app/tool/google-ai-studio.md) |
| 2 | [OpenAI Platform](https://openaitools.app/tool/openai) | 234,678,639 | -9.6% | Paid | Enterprise developer platform and API for deploying GPT-6 Astra, Sol, Luna, and realtime multimodal agents. | category: ai-api; semantic match | [.md](https://openaitools.app/tool/openai.md) |
| 3 | [OpenRouter](https://openaitools.app/tool/openrouter-ai) | 19,941,437 | -6.2% | Paid | One API key for hundreds of AI models from every major provider | category: ai-api; semantic match | [.md](https://openaitools.app/tool/openrouter-ai.md) |
| 4 | [Claude](https://openaitools.app/tool/claude-2) | 1,253,439,413 | +23.8% | Freemium | Anthropic's frontier AI workspace powered by Claude 5.5 for agentic coding, analysis, and nuanced writing. | category: ai-api | [.md](https://openaitools.app/tool/claude-2.md) |
| 5 | [DeepSeek](https://openaitools.app/tool/deepseek) | 372,761,591 | +4.3% | Freemium | High-efficiency open-weight and hosted reasoning AI powered by DeepSeek-V4 and R1 at ultra-low token costs. | category: ai-api | [.md](https://openaitools.app/tool/deepseek.md) |
| 6 | [GPTProto](https://openaitools.app/tool/gptproto) | 148,457 | +15.4% | Pay-as-you-go | One API key, one balance, 200+ text, image, video and audio models | category: ai-api; semantic match | [.md](https://openaitools.app/tool/gptproto.md) |
| 7 | [Postman](https://openaitools.app/tool/postman) | 1,764,877 | -7.6% | Freemium | Design, test, and govern APIs — now with AI agents in the loop | category: ai-api; semantic match | [.md](https://openaitools.app/tool/postman.md) |
| 8 | [Groq](https://openaitools.app/tool/groq) | 3,987,936 | +10% | Paid | Ultra-fast AI inference on the LPU and LPX platform | category: ai-api; semantic match | [.md](https://openaitools.app/tool/groq.md) |
| 9 | [v0 by Vercel](https://openaitools.app/tool/v0-dev-by-vercel-labs) | 2,774,275 | -14.3% | Freemium | Prompt to working full-stack web app, published in seconds | keywords 100%; semantic match | [.md](https://openaitools.app/tool/v0-dev-by-vercel-labs.md) |
| 10 | [MuAPI](https://openaitools.app/tool/muapi) | 412,788 | +13.7% | Freemium | One API for every generative image, video and audio model | category: ai-api; semantic match | [.md](https://openaitools.app/tool/muapi.md) |
| 11 | [AI/ML API](https://openaitools.app/tool/ai-ml-api) | 232,946 | -20.1% | Pay-as-you-go credits (free to start); enterprise custom pricing on request | One universal API for 500+ AI models and 1,000+ agentic tools | category: ai-api; semantic match | [.md](https://openaitools.app/tool/ai-ml-api.md) |
| 12 | [OrcaRouter](https://openaitools.app/tool/orcarouter) | 975,300 | -5.2% | Freemium | One OpenAI-compatible gateway for adaptive LLM routing, guardrails, and spend control | category: ai-api; semantic match | [.md](https://openaitools.app/tool/orcarouter.md) |
| 13 | [ProtoPie](https://openaitools.app/tool/protopie) | 72,414 | -23.6% | Freemium, Paid, Contact for Pricing | AI-driven high-fidelity prototyping for real interactions | keywords 100%; semantic match | [.md](https://openaitools.app/tool/protopie.md) |
| 14 | [Composio](https://openaitools.app/tool/composio) | 2,782,603 | +22.8% | Freemium, Contact for Pricing | Give your AI agents secure, authenticated access to 1,700+ apps | category: ai-api; semantic match | [.md](https://openaitools.app/tool/composio.md) |
| 15 | [EvoLink AI Model API](https://openaitools.app/tool/evolink-ai-model-api) | 312,573 | -27% | Free Trial, Paid, Contact for Pricing | One API for LLM, image, video, and audio models in production | category: ai-api; semantic match | [.md](https://openaitools.app/tool/evolink-ai-model-api.md) |
| 16 | [DeepL](https://openaitools.app/tool/deepl) | 95,110,871 | -1.7% | Freemium | Enterprise-grade neural machine translation, AI writing refinement, and real-time voice translation across thirty-plus global languages. | category: ai-api | [.md](https://openaitools.app/tool/deepl.md) |
| 17 | [Agnes AI](https://openaitools.app/tool/agnes-ai) | 902,184 | -25.8% | Freemium | One free API for text, image, and video AI models | category: ai-api; semantic match | [.md](https://openaitools.app/tool/agnes-ai.md) |
| 18 | [Pipedream](https://openaitools.app/tool/pipedream) | 312,216 | -14.3% | Freemium, Paid, Contact for Pricing | Managed auth and 10,000+ tools for the agents you're building | category: ai-api; semantic match | [.md](https://openaitools.app/tool/pipedream.md) |
| 19 | [LiteLLM](https://openaitools.app/tool/litellm) | 576,967 | +7.9% | Freemium, Contact for Pricing | One open-source AI gateway for 100+ LLM providers | category: ai-api; semantic match | [.md](https://openaitools.app/tool/litellm.md) |
| 20 | [APIMart](https://openaitools.app/tool/apimart) | 383,148 | +6.3% | Freemium, Paid | One OpenAI-compatible API for 190+ text, image, video and audio models | category: ai-api; semantic match | [.md](https://openaitools.app/tool/apimart.md) |
| 21 | [CometAPI](https://openaitools.app/tool/cometapi) | 602,966 | +49.7% | Pay-as-you-go (credits) | One OpenAI-compatible API key for 500+ AI models | category: ai-api; semantic match | [.md](https://openaitools.app/tool/cometapi.md) |
| 22 | [Atlas Cloud](https://openaitools.app/tool/atlas-cloud) | 777,031 | -16.4% | Paid | One OpenAI-compatible API for 500+ image, video, audio, and LLM models | category: ai-api; semantic match | [.md](https://openaitools.app/tool/atlas-cloud.md) |
| 23 | [Vapi](https://openaitools.app/tool/vapi) | 662,301 | -11.4% | Freemium | Build, test, and deploy production-grade voice AI agents over API | category: ai-api; semantic match | [.md](https://openaitools.app/tool/vapi.md) |
| 24 | [Bolt.new](https://openaitools.app/tool/bolt-new) | 3,033,976 | -17.8% | Freemium | Build websites and apps by chatting with AI in your browser | keywords 67%; semantic match | [.md](https://openaitools.app/tool/bolt-new.md) |

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Source: https://openaitools.app/?q=API%20prototyping

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