Krisox
Tools Add to Chrome

Compress PDF to 500 KB

Get a PDF under 500 KB, compressing only as much as needed. 100% private: it never leaves your device.

About this tool

A frequent limit for document uploads on job, visa and university portals. This tool compresses the images inside your PDF just enough to fit under 500 KB, and leaves typed text untouched. It runs in your browser, so the document is never uploaded anywhere.

Always at or under 500 KB

The result is never over the limit: it's at or under 500,000 bytes, or the tool tells you the smallest it can get with the pages still readable. Counting a KB as 1,000 bytes keeps it under the limit on sites that count 1,024 too.

What 500 KB looks like

  • A 3-page A4 scan at 300 dpi (8.8 MB) became 452.1 KB (452,054 bytes).
  • A 10-page PDF of phone photos (40.1 MB) became 479.3 KB (479,313 bytes).
  • Typed PDFs (from Word, Google Docs and the like) are mostly text, which takes little room: they are often already under the limit, and the tool then leaves them unchanged.

Tips for 500 KB

  • At 500 KB scanned pages look clean on screen, and typed text is untouched.
  • Even 10 pages of phone photos fit at 500 KB, as the measurements show.
  • If the limit is per file, upload documents separately rather than merged.

100% private

Most PDF compressors upload your document to their servers. This one works inside your browser tab: your certificate, ID scan or contract is never uploaded to Krisox or anyone else.

Questions

Will the text stay sharp?

Typed text, the kind you can select, isn't touched: only images are compressed. Scanned pages are images, so at small sizes they soften a little. Zoom in on the result before you submit it.

What if my PDF can't get under 500 KB?

The tool says so, and tells you the smallest it can get. Upload only the pages the form needs, scan in grayscale, or split the document into parts.

Is 500 KB counted as 500,000 or 512,000 bytes?

Sites differ. The tool aims under the smaller figure, 500,000 bytes, so the result fits either way.

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