Data Trackers — Extract Values from Pages

What are trackers?

Trackers let you extract specific values from a page at the time the screenshot is taken. Each tracker runs a CSS selector or JavaScript expression in the browser and captures the result alongside the image.

This is useful for monitoring dashboards, prices, rankings, or any numeric or text value that changes over time.

Predefined trackers

Ready-to-use trackers are available for common sources:

• Amazon Category Rank — product ranking in its category
• Amazon Search Rank — position in search results for a product ASIN
• Google Search Rank — position of a URL in Google search results
• YouTube Views / Likes / Comments — engagement metrics
• Twitter Retweets / Likes / Quote Tweets
• Google Maps Review Count / Score
• Page Title — the document title
• Email — extract email addresses from a CSS-selected element

Custom trackers

Define your own tracker using a CSS selector or JavaScript expression to target any value on the page:

{
  "trackers": [
    {
      "name": "Price",
      "selector": ".product-price",
      "value_type": "number"
    }
  ]
}

How to use

1. Open the Automation section in the screenshot form.
2. Under Trackers, click Add predefined tracker or Add custom tracker.
3. Configure the tracker and submit the screenshot request.
4. The extracted values appear in the screenshot response alongside the image URL.

Value types

• number — parses the result as a floating-point number.
• string — returns the raw text value.