AlterLab API Documentation
AlterLab is a web scraping API that bypasses Cloudflare, DataDome, PerimeterX, Akamai, and Kasada in a single API call. It returns clean HTML, LLM-ready markdown, or structured JSON from any URL.
The API uses a 5-tier auto-escalation system: Tier 1 (Curl, $0.0002/req) for static sites, Tier 2 (HTTP, $0.0003/req) for TLS-fingerprinted requests, Tier 3 (Stealth, $0.002/req) for anti-bot bypass, Tier 4 (Browser, $0.004/req) for JavaScript rendering, and Tier 5 (Captcha, $0.02/req) for CAPTCHA solving. Official SDKs are available for Python and Node.js. Pay-as-you-go pricing with no monthly subscription — balance never expires.
New to AlterLab?
Getting Started
Installation
Install the SDK in your preferred language and set up your environment.
Your First Request
Make your first API call and scrape a web page in under 2 minutes.
REST API Reference
Complete reference for all API endpoints, parameters, and responses.
Python SDK
Official Python SDK with async support, batch operations, and type hints.
Guides
JavaScript Rendering
Scrape SPAs and dynamic sites with headless browser rendering.
PDF & OCR
Extract text from PDFs and images with multi-language OCR support.
Caching
Reduce costs with intelligent caching. Cache hits are free.
Webhooks
Get notified when async scrapes complete with webhook callbacks.
JSON Schema Filtering
Filter extracted data to match your desired output structure with aliases and type coercion.
Batch Scraping
Submit up to 100 URLs in a single API call with async processing and webhooks.
Scheduler
Automate recurring scrapes with cron expressions and balance-based limits.
Authenticated Scraping
Scrape login-gated content with your own session cookies. Member pricing, paywalled articles, and more.
Tutorials
Reference
Pricing
Tier costs, add-ons, BYOP discounts, and concurrency limits.
Rate Limits
Quotas, payload limits, timeouts, and how to handle 429 errors.
Error Codes
Complete list of error codes with troubleshooting tips.
API Keys
Manage API keys, permissions, and security best practices.
Quick Links
Interactive Playground
Test API requests in real-time with our interactive tool
Bring Your Own Proxy
Use your own proxies for up to 20% cost savings
Migrate from Firecrawl
Switch from Firecrawl with our compatibility layer
Compare with Alternatives
See how AlterLab compares to ScraperAPI, Firecrawl, and others
See Also
Blog & Tutorials
Web scraping guides, anti-bot bypass techniques, and code examples
Pricing
5-tier pricing from $0.0002/request. Pay-as-you-go, credits never expire
Compare Scraping APIs
AlterLab vs ScraperAPI, Firecrawl, ScrapingBee, and Bright Data
Anti-Bot Bypass
Bypass Cloudflare, DataDome, PerimeterX, and Akamai automatically