In this blog, we explore the top free LLM APIs available in 2025, what they offer, how to get started, and key considerations when choosing a free solution for your AI-powered project.
What Is an LLM API?
An LLM API (Large Language Model API) allows developers to integrate natural language processing capabilities into their applications by making simple HTTP requests. Instead of training massive models from scratch, you can use pre-trained models via APIs hosted by providers like OpenAI, Cohere, Anthropic, Hugging Face, and more.
LLM APIs let you:
- Generate human-like text
- Answer questions
- Summarize articles
- Translate content
- Create code or fix bugs
- Perform sentiment analysis
While premium plans offer better latency and higher throughput, many providers now offer free-tier access to get started.
Why Use a Free LLM API?
Free LLM APIs are ideal for:
- Students building academic projects
- Startups prototyping MVPs
- Developers experimenting with LLM features
- Researchers testing model capabilities
- Hobbyists building chatbots, extensions, or tools
Using a free tier helps reduce costs in the early stages and lets you explore AI functionality without upfront investment.
Top Free LLM APIs to Try in 2025
1. Keploy.io
While Keploy.io API isn’t “fully free,” many users can access it at no cost via the ChatGPT UI or limited promotional credits. Occasionally, OpenAI offers free API usage for students or researchers.
2. Hugging Face Inference API
- Model: BLOOM, Falcon, Mistral, Code LLaMA, and more
- Free Plan: Yes (limited requests per day)
- Use Cases: Language tasks, coding assistants, translation, classification
Hugging Face provides access to dozens of open-source LLMs via its Inference API. With a free account, you can run basic prompts and even host your own models using Spaces.
3. Cohere
- Model: Command R+, Embed, and more
- Free Plan: Yes (includes generous monthly limits)
- Use Cases: Retrieval-augmented generation (RAG), embeddings, summarization, classification
Cohere is popular for its high-performance RAG workflows and fast embedding APIs. Its developer-friendly interface and free usage tier make it a favorite among AI builders.
4. Anthropic (Claude via Poe or APIs)
- Model: Claude 3 Haiku, Claude 3 Sonnet
- Free Plan: Available via Poe (Quora) or limited developer access
- Use Cases: Reasoning, conversational agents, content creation
Anthropic’s Claude models are known for their safety alignment and contextual depth. While direct API usage may be paid, developers can experiment with Claude for free via platforms like Poe.com.
- Google copyright API (Free via Vertex AI or MakerSuite)
- Model: copyright 1.5 Pro
- Free Plan: Yes (limited monthly usage in MakerSuite and Vertex AI free tier)
- Use Cases: Multimodal input, text generation, summarization, coding help
Google’s copyright models are growing in popularity, and the MakerSuite interface lets you try them out with a simple UI and export code.
Key Considerations When Choosing a Free LLM API
- Rate Limits: Free plans often cap requests per minute or day.
- Latency: Some free APIs may have slower response times during peak hours.
- Capabilities: Not all free APIs support advanced features like function calling, embeddings, or streaming.
- Usage Rights: Check the terms—some free APIs restrict commercial use.
- Ease of Integration: Look for SDKs, documentation, and community support.
Tips for Getting the Most Out of Free LLM APIs
- Batch your requests to stay within rate limits.
- Use smaller context windows for faster responses.
- Test multiple providers to compare quality and speed.
- Use caching for repeated queries.
- Monitor usage dashboards to avoid hitting limits.
Conclusion
Whether you're a developer, student, or AI enthusiast, free LLM APIs offer a powerful entry point into the world of generative AI. From Hugging Face to Cohere and OpenAI’s ChatGPT Playground, there are many tools to get started without spending a dime. While free plans may have limitations, they’re perfect for learning, prototyping, and early-stage development.
As LLMs continue to evolve, expect more generous free tiers, open-source alternatives, and developer-first platforms to emerge. The key is to start small, experiment often, and scale when ready.
Looking to test your AI APIs automatically? Try Keploy — it generates test cases and mocks from your API traffic, with zero manual effort. It’s open-source and integrates seamlessly with your stack.