How to compress a PDF to under 200 KB
Last updated 2026-10-05
Application portals and email systems often reject a PDF over a fixed size such as 200 KB. A scanned page can easily be several megabytes, so the file has to shrink by 90 per cent or more. This guide shows how to get there and what you give up on the way.
Know what the limit actually counts
Most forms that say 200 KB count 1 KB as 1,000 bytes, so a file of 200,000 bytes or less passes. Some count 1,024. Aim a little under the number rather than exactly on it: a target of 190 KB passes under either rule.
Check whether the limit applies to one file or the whole upload, and whether it is a maximum only. A few portals also set a minimum size, in which case an over-compressed file can be rejected for being too small.
Why scans are big and text PDFs are small
A PDF made from a word processor stores text as text, so a typed page is often only tens of kilobytes. A scan stores each page as a picture, and a full-page colour photograph at scanner resolution runs to megabytes. Compression only has a big job to do on the picture kind.
If your PDF is already small and the portal still complains, check the page count and any embedded photos. If it is a text document that is simply over the limit, the quickest saving is usually removing pages you do not need rather than compressing.
Compress to a target size
Open Compress PDF, add your file, and on the Target file size tab enter the limit in KB. The tool renders each page, re-saves it as a JPEG inside a new PDF, and lowers the resolution and quality until the whole file fits, then shows the final size and page count. Nothing is uploaded; the work happens in your browser.
Type a figure just under the limit, such as 190 for a 200 KB limit. If the result still looks too rough, raise the target a little, or cut the page count and compress again, because a fixed size is shared between pages and fewer pages each get more of it.
What you lose, and when that matters
Because pages become images, text in the compressed copy can no longer be selected or searched, and very small targets make small print soft. For an identity scan or a certificate that someone only needs to look at, that is fine. For a document that must stay searchable or be copied from, keep the original and send fewer pages instead.
Always open the compressed file and read it before uploading, especially numbers and signatures. Keep the original: a compressed copy cannot be restored to the quality of the scan.
If it will not get small enough
Split the document into parts and compress each, if the portal allows several files. Rescan at a lower resolution, since 150 dpi is usually legible and far smaller than 600. Check that the PDF is not password-protected, which the tool rejects. If the original is already under the limit, the tool leaves it unchanged and says so.