Supacrawler vs Selenium

Selenium is the most popular browser automation framework, originally designed for testing web applications. We benchmarked it against Supacrawler for JavaScript-heavy web scraping tasks.

Key Differences

Selenium excels at browser automation and testing but has significant overhead for scraping. Supacrawler is purpose-built for high-performance data extraction with Go-based streaming architecture.

Test Environment: Mac M4, 24GB RAM, Python 3.11, JavaScript rendering enabled (render_js=True), identical retry logic (3 retries, exponential backoff), 10s timeouts.

Performance Benchmarks

Single Page Performance (https://supabase.com with JavaScript):

Supacrawler is 3.0x faster despite identical JavaScript rendering.

Multi-Page Crawling Performance:

Large-Scale Testing (50 pages per site):

Technical Architecture Comparison

Selenium Sequential Processing:

# One URL at a time - sequential bottleneck
for url in urls:
    driver.get(url)      # Block until complete
    extract_data()       # Process sequentially
    # Move to next URL

Supacrawler Go Streaming:

// Concurrent worker pool with goroutines
maxWorkers := 10  // Dynamic based on workload
for i := 0; i < maxWorkers; i++ {
    go worker()  // Parallel processing
}
// Stream results as they complete

Performance Advantages:

• Go Concurrency: Goroutines vs Python sequential execution
• Streaming Architecture: Process results as they arrive vs batch processing
• Memory Efficiency: Go's optimized memory model vs Python/Chrome overhead
• Infrastructure: Managed cloud browsers vs local browser management

The Content Quality Trade-off

Selenium Raw Output:

Supabase | The Postgres Development Platform. Product Developers 
Solutions Pricing Docs Blog 88.3K Sign in Start your project...

Supacrawler LLM-Ready Output:

# Build in a weekend, Scale to millions

Supabase is the Postgres development platform.

Start your project with a Postgres database, Authentication...

Supacrawler automatically removes navigation, ads, and boilerplate while preserving structured content in clean markdown format - faster than Selenium while delivering higher data quality.

Use Cases

Setup Complexity

Selenium Setup:

1. Install browser drivers
2. Manage Chrome/Firefox versions
3. Configure headless options
4. Handle browser crashes
5. Implement retry logic
6. Scale infrastructure

Supacrawler Setup:

1. Get API key
2. pip install supacrawler
3. Start scraping

Getting Started

Selenium: Install drivers → Configure browsers → Write retry logic → Handle crashes → Scale infrastructure → Clean data manually

Supacrawler: Get API key → pip install supacrawler → Start getting clean data immediately

See detailed benchmarks: Supacrawler vs Selenium Performance Analysis