About LangSearch
LangSearch is a web search API and semantic rerank API designed to connect LLM applications to the world, providing clean, accurate, and high-quality context. It supports natural language search and offers enhanced search details from billions of web documents, including news, images, and videos. LangSearch uses a hybrid search database and semantic reranker, supporting mixed keyword and vector searches, and employs an advanced LangSearch Ranker Model to boost search result accuracy.
How to Use
Integrate the LangSearch API directly or use LLM tools and AI agent plugins in your applications. The API can be called flexibly, supporting custom filtering conditions. Use the provided curl command or LLM tools like LangChain for integration.
Key Features
- Web Search API supporting natural language search
- Semantic Rerank API
- Hybrid search database supporting mixed keyword and vector searches
- LangSearch Ranker Model for improved search accuracy
- Easy integration with LLM tools and AI agent plugins
Use Cases
- Enhancing search details in LLM applications
- Improving the accuracy of search results
- Connecting LLM applications to real-world data
- Building AI Agents, AI Chatbots, AI Search, and RAG applications
Key Features
Web Search API supporting natural language search
Semantic Rerank API
Hybrid search database supporting mixed keyword and vector searches
LangSearch Ranker Model for improved search accuracy
Easy integration with LLM tools and AI agent plugins
Pros & Cons
Pros
- Completely free for individuals and small teams, no hidden costs
- High accuracy through hybrid keyword/vector search and advanced reranker
- Fast inference with small model size (80M params) outperforming larger models
- Rich context retrieval including news, images, and videos
- Flexible integration with popular LLM frameworks and custom workflows
Cons
- Free tier may have rate limits for high-volume usage (not explicitly stated)
- Limited to web search and semantic rerank—not a general-purpose AI platform
- No enterprise-specific features (e.g., dedicated support, SLAs) currently mentioned
Best For
Enhancing search details in LLM applicationsImproving the accuracy of search resultsConnecting LLM applications to real-world dataBuilding AI Agents, AI Chatbots, AI Search, and RAG applications
Alternatives to LangSearch
FAQ
Is LangSearch really free?
Yes, LangSearch is absolutely free for individuals and small teams. No fees, no subscriptions, and no credit card required. There are no hidden costs.
What is the LangSearch Rerank model?
The LangSearch Rerank model is a transformer-based reranker with 80 million parameters. It achieves ranking performance comparable to 280M–560M models while offering faster inference and lower cost.
How do I integrate LangSearch into my application?
You can integrate LangSearch API directly using curl, or use LLM tools like LangChain and AI agent plugins. The API supports custom filtering conditions and can be called flexibly.
What types of search does LangSearch support?
LangSearch supports natural language search and provides enhanced results from billions of web documents, including news, images, and videos. It uses a hybrid search database combining keyword and vector searches.
Does LangSearch require a credit card to start?
No, absolutely not. LangSearch is free to use without any credit card or upfront payment.