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Monitor a PDF File for Changes

Available on Flexi and Enterprise plans.

Distill lets you monitor PDF files hosted at a public URL. PDF monitoring runs on Distill’s servers only. Local monitoring is not supported.

Add a PDF Monitor

  1. Open the Watchlist: https://monitor.distill.io

  2. Click Add Monitor → PDF

    Add PDF Monitor

  3. Enter the PDF URL in the Source field, then click Save

    Enter the URL

    Tip: Right-click a PDF link on a webpage and select Copy Link Address to get the PDF URL.

  4. On the Options page, configure the check interval and alert actions, then save your changes

    Configure Options

Your PDF monitor is now active. To view the monitored content, click the monitor’s text preview. When Distill detects a change, you’ll receive alerts based on the actions you configured.

View Change History

Compare PDF Versions

You can use Change History to compare different versions of the same PDF.

  1. Open the monitor’s Change History
  2. Click Explore diff under a change entry
  3. Review the highlighted differences between versions
Explore PDF Diff

Some websites update the PDF URL regularly, even though the document stays in the same place on the site. In that case, use two monitors:

  1. A PDF monitor for the current PDF URL
  2. A web page monitor for the page that contains the PDF link, configured to track the link’s href attribute

When the page monitor detects that the link has changed, update the PDF monitor with the new URL.

Example: Monitor IRS Form 1040

Step 1: Add a PDF Monitor

Create a PDF monitor using the current Form 1040 URL:

https://www.irs.gov/pub/irs-pdf/f1040.pdf

Add PDF URL

Step 2: Add a Web Page Monitor for the PDF Link

Create a web page monitor for:

https://www.irs.gov/forms-pubs/about-form-1040

Add Web Page Monitor

Then:

  • Select the Form 1040 link element on the page
  • Expand the selection panel to show selectors and preview
  • Find href in the attributes list and select it
  • Save the monitor and configure the check interval and alert actions
Edit Options

Note: The href attribute is not shown visually on the page. To view it, open Change History and switch from Visual view to Text view.

Text View

When the page monitor reports a new PDF link, update the existing PDF monitor.

Update the PDF URL

  1. Open the PDF monitor’s Options page

    Edit Options

  2. Click Edit

  3. Replace the old PDF URL with the new one

  4. Click Save

    Edit Options

FAQ

Can I monitor only part of a PDF?

No. PDF monitors track the entire document. Partial monitoring is not supported.

Can I monitor PDFs stored on my local device?

No. PDF monitors run on Distill’s cloud servers and require a publicly accessible URL. Local files are not supported.

Are there file size limits for PDFs?

There is no hard size limit. However, very large PDFs may take longer to load and may cause parsing errors if the file cannot be processed successfully.

Can I monitor password-protected PDFs?

No. Password-protected PDFs cannot be monitored.

What happens if a monitored PDF is deleted?

The monitor will show an error if the PDF is deleted or no longer available.

Troubleshooting

If your PDF monitor shows an error, check the error code in the Check Log.

Error Code Cause Solution
ERR_PDF_PARSE Distill downloaded the file but could not parse it. The file may not be a valid PDF or may use an unsupported format. Wait for a few checks to see whether the issue resolves automatically.
E_DOWNLOAD The PDF could not be downloaded completely, possibly due to a network interruption. Distill will automatically retry.
E_PDF_UNKNOWN_TYPE The server did not return a PDF file. This can happen if the URL does not point directly to a PDF, or if the site blocks automated requests or requires cookies. Verify that the URL points directly to a PDF and that the site allows automated downloads.

If the issue continues after several checks, contact support@distill.io.

Video Guides

Watch the step-by-step tutorial on creating a PDF monitor:

For advanced PDF monitoring techniques, including comparing PDFs and tracking changing PDF links, watch this video.

Note: PDF files are larger and require more processing resources. Each PDF check counts as 2 checks toward your plan limits.

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