smart rendering apijavascript rendering apidynamic content extraction

Smart Rendering API

Automatic website compatibility for JavaScript-heavy and dynamically rendered pages. AlterLab's smart rendering pipeline selects the right approach for each URL — from simple fetch to full browser rendering. From $0.0002/request, no monthly subscription.

No credit card
SOC 2 aligned
99.9% uptime
Simple Pricing
$1
One dollar
=
5,000
Requests
Pay as you go
No subscriptions
Never expires
2,847,653+
Requests processed this week
Developer Experience

Simple API, Powerful Results

Get started in minutes with our intuitive API. One request gives you structured data, screenshots, PDFs, and more. No browser management, no infrastructure headaches.

Multi-Format Output

Markdown, JSON, HTML, text

Adaptive Rendering

JS, SPAs, shadow DOM

3 Lines to Integrate

Any language, any stack

Request
Response
200 OK·1.2s

Up to 5,000 free scrapes included. No credit card required.

How the Smart Rendering Pipeline Works

AlterLab automatically selects the right rendering approach for each URL — no configuration needed.

1

Site Compatibility Analysis

When you send a URL to the AlterLab API, the system first analyzes the site's rendering requirements. Some sites serve complete HTML immediately; others require JavaScript execution, cookie handling, or challenge resolution. AlterLab detects these requirements and routes the request to the most efficient rendering tier automatically — no manual configuration needed.

2

Adaptive Request Handling

AlterLab crafts each request to match the expectations of the target site — appropriate headers, HTTP/2 framing, and request timing that matches real browser behavior. This ensures high compatibility with modern web infrastructure, including CDNs and edge services that validate request characteristics. See our technical deep-dive on browser compatibility for details.

3

Full Browser Rendering

For sites that require complete JavaScript execution — single-page applications, infinite scroll pages, or sites with interactive content — AlterLab escalates to a full headless browser environment. The browser renders the page in a real Chromium instance with residential proxy IPs and accurate viewport settings, ensuring JavaScript-dependent content is fully loaded before returning the HTML.

4

Automated Challenge Resolution

Some sites present interactive verification steps before serving content — image selection tasks, audio challenges, or puzzle-based checks. AlterLab automatically handles these verification steps using AI-powered solvers. Challenge resolution only activates when detected, keeping costs low. You send a URL and receive clean HTML content — the full pipeline runs transparently.

Automatic Tier Escalation

Starts with the fastest approach, escalates only when needed. Pay only for what works.

Automatic Tier Escalation

Starts with the fastest approach, escalates only if needed. Pay only for what works.

Challenge Resolution

Automatically handles interactive verification steps using AI-powered solvers.

Full Browser Rendering

Real Chromium rendering for JavaScript-heavy and single-page applications.

Residential Proxies

Rotating residential IPs included. No proxy management.

Why Use AlterLab Instead of Building Your Own Pipeline

Building a reliable web data extraction pipeline is possible — but it comes with hidden operational costs.

DIY Rendering Pipeline

  • ×Maintain proxy pools across multiple providers ($200+/month for residential IPs)
  • ×Update request handling as web infrastructure evolves
  • ×Manage headless browser infrastructure (Puppeteer/Playwright clusters)
  • ×Integrate challenge resolution services separately
  • ×Debug constantly as site rendering requirements change

AlterLab Smart Rendering API

  • One API call handles everything — no proxy management, no browser infrastructure
  • Always up to date — AlterLab updates rendering capabilities automatically
  • Pay-per-request from $0.0002 — no monthly subscription or minimum commitment
  • Built-in challenge resolution, residential proxies, and full browser rendering
  • High compatibility across static, dynamic, and JavaScript-heavy sites

At 10,000+ requests per month, the engineering hours spent maintaining a DIY rendering pipeline far exceed the cost of an API. AlterLab handles the constantly evolving web rendering landscape so you can focus on extracting and using the data. See how AlterLab compares to other web scraping APIs on price, features, and success rates.

Reliable Data Extraction Across Industries

High compatibility with dynamic and JavaScript-rendered websites across verticals.

E-commerce Data

Extract product data, pricing, and inventory from dynamic retail sites

Price Monitoring

Track competitor pricing from JavaScript-rendered product pages

Travel & Booking

Scrape flight prices and hotel rates from dynamic booking sites

Financial Data

Extract stock prices and financial data from complex web applications

Most Cost-Effective Solution

Only pay for the rendering tier needed for each URL.

Why Teams Switch to AlterLab

Smart routing, no subscriptions, balance that never expires

Feature
AlterLab
You are here
ScraperAPIBright DataFirecrawl
Avg cost (real workload)
Smart routing vs flat rate
~$0.001$0.00049/credit$0.0015$0.0063
Simple scrape
Basic HTTP request
$0.0002$0.00049$0.0015$0.0063
JS rendering
Full browser render
$0.004$0.0049$0.0015$0.0063
Free tier
Free requests to start
Up to 5,000 scrapes5,000 creditsNone500 scrapes
Minimum
Smallest purchase
$10 one-time$49/month$0 (PAYG) / $499/mo (subscription)$19/month
Balance expires?
Does unused balance expire
NeverMonthlyNever (prepaid) / Monthly (subscription)Monthly
CAPTCHA solving
Built-in CAPTCHA bypass
$0.02/solveExtra costExtra costNot available

Avg cost based on typical content/SEO workload (75% simple, 25% protected). Competitor prices from public pricing pages, March 2026.

Frequently Asked Questions

Your first scrape.
Sixty seconds.

$1 free balance. No credit card. No SDK.Just a POST request.

terminal
curl -X POST https://api.alterlab.io/v1/scrape \
-H "X-API-Key: YOUR_KEY" \
-H "Content-Type: application/json" \
-d '{"url": "https://example.com", "formats": ["markdown"]}'

No credit card required · Up to 5,000 free scrapes · Balance never expire