0 requests since your file/works offlineYour desk

Why is my PDF so large?

Drop the file and get its byte budget: how much is images, fonts, duplicated images and everything else, with the biggest offenders listed and a fix for each.

Diagnostic · runs in this tab · free
Size X-rayRead in this tab, never run
Drop a PDF anywhere on this pageThe instant X-ray reads the raw bytes; the full inspector then parses every object in a Web Worker. Nothing is uploaded or executed.
What you’ll see
  • Byte budget: images, fonts, page content, duplicates, attachments, metadata
  • The largest images with pixel size, effective dpi and the pages they are on
  • Every cause linked to the tool that fixes it
Requests since you added a file: 0Counted by this page · check it without trusting us

The usual suspects

Scanned pages and phone photos stored at full camera resolution are the most common cause: a photo straight from a phone camera often takes several megabytes on its own, and a colour scan at 300 dpi stores four times the pixels of the same scan at 150 dpi. Resampling to 150 dpi usually keeps text readable at a fraction of the size.

The same image stored many times (a logo or letterhead added on every page by some tools) is the second; de-duplication fixes it without any quality change. Fully embedded fonts, especially Asian fonts, add hundreds of kilobytes each. Attachments inside the PDF and leftover data from repeated “Save” operations can add more.

The quick scan reads the raw file instantly; the full inspector then parses every object, including compressed object streams, and lists each image with its pixel size and effective dpi.

Steps

  1. Drop the PDF.
  2. Read the instant X-ray.
  3. The full inspector then lists the largest images with their resolution and pages.
  4. Follow the fix next to each cause.

Limits, stated plainly

  • Byte budgets count stored (compressed) bytes, which is what the upload limit sees.

Engine: Quick scan in this tab; full inspector with pdf-lib in a Web Worker. Your file is not uploaded; check it yourself.