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Compressing

How to Get a PDF Under 1MB

A practical route to the 1MB mark — what to remove first, how far to compress, and when the target simply is not reachable.

May 16, 20262 min read

1MB is the most common hard limit on the web — application portals, ticketing systems, older content management systems. It is comfortably achievable for most documents and impossible for a few, and knowing which you have saves a lot of frustration.

Is 1MB realistic for your file?

DocumentUnder 1MB?
Text document, any lengthEasily — often under 200KB already
1–5 scanned pages, greyscaleYes, with moderate compression
10–20 scanned pagesUsually, at 150 DPI
50+ scanned pagesOnly by cutting pages
Photo brochureOnly at quality nobody would accept

The order to try things

  1. 1Remove pages the recipient does not need. Nothing else saves as much.
  2. 2Convert colour scans to greyscale.
  3. 3Compress at a moderate setting and check the size.
  4. 4Increase compression a step at a time, checking readability as you go.
  5. 5Reduce the resolution to 150 DPI if you still need more.
  6. 6Stop and reconsider if the text is becoming hard to read — an illegible document under the limit is still a failure.

What to do when you cannot get there

  • Split into parts if the system accepts multiple uploads.
  • Rescan at 200 DPI greyscale rather than crushing a 600 DPI colour scan.
  • Upload only the pages that were actually asked for.
  • Ask whether a link is acceptable — surprisingly often it is.

Check the units

Some systems mean 1,000,000 bytes and some mean 1,048,576. If your 1.0MB file is being rejected, aim for 950KB and the ambiguity stops mattering.

Where the size actually is

Before compressing, work out what is heavy. Try to select text: if you cannot, the document is scanned images and compression will do most of the work for you. If you can, and it is still large, look for photographs — a single high-resolution image can account for most of a file, and replacing it with a smaller version beats compressing the whole document.

A repeated background, such as a scanned letterhead placed on every page, is the other common culprit. It compresses well but the real fix is removing the repetition.

Getting it right at capture

If you are producing the document rather than receiving it, capture at the size you need. A page scanned at 200 DPI greyscale arrives under the limit without any compression at all, and it looks better than the same page scanned at 600 DPI colour and then crushed to fit.

Do it now

Compress PDF

Reduce file size while maintaining quality. It runs in this browser tab — your file is not uploaded anywhere.

Open Compress PDF

Frequently asked questions

What is the fastest way to get under 1MB?+

Remove pages that are not needed, then compress. Page count is the biggest single factor in a scanned document.

Will my scan still be readable at 1MB?+

For a handful of pages, yes. Across fifty pages you are down to 20KB a page, which is not enough for legible scanned text.

Does zipping help?+

Almost never. PDFs are already compressed internally.

My file says 1.0MB and is still rejected. Why?+

Rounding, or a difference between MB and MiB. Target 950KB.

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