AI API

LangSearch

Free web search API and semantic rerank API for LLM applications — connect AI agents to real-time web data.

langsearch.com

Verified API available Free tier

Quick facts
What is it	Free web search API and semantic rerank API for LLM applications — connect AI agents to real-time web data.
Pricing	Free
Free tier	Yes
Platform	Web Application
API	Yes
Best for	Enhancing RAG applications with real-time web data, Improving AI chatbot accuracy with current information

Data updated Aug. 1, 2026

What does LangSearch do?

LangSearch provides API services that connect large language model applications to real-world web data. It offers two core services: a web search API that allows natural language queries across billions of web documents, and a semantic rerank API that improves search result accuracy. The system returns clean, structured JSON responses with detailed metadata including summaries, publication dates, and source information, making it easy for developers to integrate fresh web content into their AI applications.

What sets LangSearch apart is its hybrid search approach combining keyword and vector searches, along with its proprietary semantic reranker. The reranker uses transformer architecture to achieve performance comparable to much larger models while maintaining only 80M parameters, resulting in faster inference and lower costs. The API is designed specifically for LLM integration, with optimized response formats for function calling and support for custom filtering conditions.

This tool is particularly valuable for developers building AI agents, chatbots, and RAG (Retrieval-Augmented Generation) applications that need access to current web information. Instead of relying on static knowledge bases, these applications can use LangSearch to pull real-time data from news sites, documentation, and other web sources, significantly improving the relevance and accuracy of their responses. The free tier with no credit card requirement makes it accessible for prototyping and testing.

AI API Developer Tools LLM Web Scraping

#ai agents#developer tools#llm integration#natural-language search#rag#semantic-reranking#web search api

Key features

What makes it stand out

Natural language web search API with detailed JSON responses

Semantic reranker with transformer architecture for accurate results

Hybrid search database supporting mixed keyword and vector searches

Easy integration with LLM tools like LangChain and OpenAI function calls

Pre-built plugins for AI agent platforms like Coze, Dify, and Wordware

Who is LangSearch for?

Who benefits most from this tool

Enhancing RAG applications with real-time web data

Improving AI chatbot accuracy with current information

Building AI agents that need web search capabilities

Pricing

Free tier available — start without a credit card

Free

Free web searches
Free summary content pieces
1k searches searches 1 50 documents
1k searches searches 50 100 documents
Keyword & embedding based hybrid search
Natural language search support
Long-text summary from raw content
Markdown formatting support
Semantic reranker for search accuracy
Works with any keyword or vector search system

Gallery

Click any image to enlarge

LangSearch — pricing page — Pricing page

Alternatives in AI API

Reranker by Contextual AI AI API

AI-powered document reranking API — improves RAG systems by prioritizing the most relevant content for LLM responses

AnySearch AI API

AI search infrastructure for agents — one API to query structured data across 20+ domains

API Pick AI API

A curated collection of REST APIs for real-time web search, content extraction, and structured data enrichment.

Mindware AI API

A single API gateway that gives AI agents access to multiple services like translation, search, and payments without coding.

DeepSeek API Docs AI API

API for DeepSeek's LLM models — drop-in replacement for OpenAI/Anthropic, works with existing tools

Cloudsway AI API

Infrastructure for AI agents — real-time search, model routing, and a secure execution sandbox

n8n

Scavio AI AI API

A real-time search API for AI agents — search Google, Amazon, YouTube, Walmart, and Reddit from a single endpoint.

KeyAPI.ai AI API

A unified API for accessing data from 20+ social media and web platforms, designed for AI agents and automation.

Similar tools

SearchCans Web Scraping

API platform for real-time Google/Bing search results and web page content extraction for AI agents.

LangWatch Testing

Open-source testing platform for AI agents. Run simulations, catch regressions, and ship autonomous agents with confidence. Built for developers who treat AI like software. Agent simulations are the new unit tests

n8n

LangChain Developer Tools

Framework and platform for building, testing, and deploying AI agents with observability and evaluation tools.

Top 100k site

Langbase Developer Tools

Serverless platform for developers to build, deploy, and scale AI agents with a unified API.

ReactiveSearch Developer Tools

Open-source stack for building AI-powered search UIs — pipelines, analytics, and UI kits for React, Vue, Flutter, and JS

Langflow No-Code&Low-Code

Low-code visual builder for creating and deploying AI agents and RAG applications.