Compress PDF to 40 KB

Reduce any PDF to 40 KB or less, free and private — no sign-up, no watermark.

This tool runs entirely in your browser. Your file never leaves your device — nothing is uploaded to our servers, so confidential documents and photos stay private.

Compress PDF to 40 KB online — free and exact

Need a PDF under 40 KB? This free tool automatically reduces your PDF until it fits within 40 KB, then lets you download it. It works by intelligently re-rendering each page and tuning quality and resolution in your browser until the smallest readable file that meets your 40 KB target is reached — so you get the exact size limit you need without trial and error. 40 KB is the most common upload ceiling on university admission portals, scholarship applications, KYC and bank document forms, and online job applications. Compress your PDF to 40 KB here and attach it without the form bouncing it back.

How to compress pdf to 40 kb

1
Drop your PDF into the box above (or click to browse). It is processed entirely in your browser — nothing is uploaded.
2
Press "Compress to 40 KB". The tool re-renders the pages and tunes quality automatically to fit within 40 KB.
3
Watch the achieved size — it tells you the final file size once compression finishes.
4
Download your compressed PDF and upload it to your form, portal or email straight away.

Frequently asked questions

How do I compress a PDF to 40 KB?+

Upload your PDF above and click "Compress to 40 KB". The tool automatically lowers the resolution and image quality of each page just enough to fit within 40 KB, then offers the file for download. Everything happens in your browser, so your document is never uploaded.

Is compressing a PDF to 40 KB free?+

Yes — completely free with no watermark, no sign-up and no daily limit. You only need an account if you want your history saved.

Will the quality drop when I compress to 40 KB?+

To reach a small target like 40 KB, pages are re-rendered as optimised images, so very fine detail softens. The tool always keeps the highest quality that still fits 40 KB, so text stays clearly legible for form and portal uploads. If you don't need an exact size, use the standard Compress PDF tool for lighter, higher-quality compression.

Is it safe to compress confidential documents to 40 KB here?+

Yes. This tool runs 100% in your browser — your PDF never leaves your device and is never sent to any server, so ID cards, certificates and bank statements stay private.

What if my PDF can't be compressed all the way to 40 KB?+

Some PDFs with many pages or dense text can't physically reach 40 KB while staying readable. In that case the tool produces the smallest readable file it can and shows you the achieved size — often you can then split the PDF or remove unneeded pages to get under 40 KB.