Fast Scan vs Detailed Scan vs JS Rendering
PerfBee's Site Crawler is a powerful tool for identifying broken links, SEO issues, and other problems on your website. Understanding the different scan modes is key to optimizing your crawl strategy and credit usage. This article explains the differences between Fast Scan, Detailed Scan, and JS Rendering.
Fast Scan
The Fast Scan is the most basic and cost-effective option. It checks for:
- HTTP status codes (e.g., 200 OK, 404 Not Found, 301 Redirect).
- Basic metadata (e.g., title tag, meta description).
This scan is ideal for quickly identifying broken links and basic issues, especially on large sites. It consumes the fewest credits.
Detailed Scan
The Detailed Scan offers a comprehensive SEO audit of each page, performing over 20 different checks. This includes all the checks of the Fast Scan, plus:
- Advanced SEO analysis (e.g., keyword density, heading structure, canonical tags, image alt text).
- More in-depth checks for redirects and other potential SEO issues.
The Detailed Scan is more resource-intensive and consumes more credits, but it provides a much deeper understanding of your site's SEO health.
JS Rendering
The JS Rendering option uses a headless browser (Playwright) to render the page, allowing the crawler to see the content as a user would after JavaScript execution. This is crucial for websites built with:
- Single-Page Applications (SPAs)
- React, Vue, and Next.js sites
- Websites that heavily rely on JavaScript to load content
JS Rendering consumes more credits due to the increased resources required.
When to Use Each Mode
Here's a quick guide to help you choose the right scan mode:
- Fast Scan: Use for a quick check of a large site or when you only need to identify broken links and basic metadata issues.
- Detailed Scan: Use for a thorough SEO audit and to identify more complex issues on your site.
- JS Rendering: Use for websites that heavily rely on JavaScript to render content. This is essential for SPAs and modern JavaScript frameworks.
Credit Cost Comparison
The credit cost varies based on the scan mode and whether the site is owned or not. Remember, your credit balance is always visible in the top-right of the dashboard at PerfBee Dashboard.
| Scan Mode | Owned Site | Non-Owned Site |
|---|---|---|
| Fast Scan | 0.5 credits/page | 1 credit/page |
| Detailed Scan | 1 credit/page | 4 credits/page |
| JS Rendering | 2 credits/page | 4 credits/page |
How to Configure Scan Mode
The scan mode is set within the preset configuration when setting up a new scan. Here's how:
- Log in to your PerfBee account at PerfBee Dashboard.
- Navigate to the Broken Links tab.
- Click the "Add New Scan" button.
- Choose a preset configuration (or create a custom one).
- Select your preferred Scan Mode: Fast, Detailed, or JS Rendering.
- Configure other scan settings as needed.
- Click "Save & Run" to start the scan.
By understanding the differences between these scan modes, you can optimize your use of PerfBee's Site Crawler and get the most value from your credits. For more information, please consult the PerfBee Documentation.