Compress PDF to KB

about this tool

Bring a PDF under the size a form asks for

Upload forms for exams, jobs, visas and loans set a size for each document — a marksheet under 200 KB, an ID proof under 100 KB, everything under 1 MB — and refuse anything bigger. Choose the PDF, pick the limit (or type your own, such as 250 KB or 1.5 MB), and press Compress.

The gentlest change that fits

The page stops at the first of these that gets the file under the limit:

1. Already small enough. The file is kept exactly as it is.
2. Rewritten. Its streams are recompressed and any photos inside are re-encoded as JPEG — first gently, then a little harder. Text stays text: you can still select it, search it and copy it.
3. Pages as pictures. Each page is drawn and saved as a JPEG, trying resolutions from 150 down to 50 dots per inch and qualities from 85% down to 25%, and keeping the clearest result that fits — preferring a lower resolution to blocky compression. Text then becomes part of the picture: still there to read, a little softer, but it cannot be selected, copied or searched. The result shows the first page so you can check the small print. Up to 80 pages can be drawn this way in a browser.

The result says which of these it used. If you need the text to stay selectable, switch on Keep text copyable and searchable: the page will only rewrite the file, and if that is not enough it says how small it got. Greyscale pages turns every page grey before it is saved as a picture, which shrinks scans of text a long way; it changes nothing when the file fits by being rewritten.

Counting KB the strict way

Some forms count a KB as 1,000 bytes and some as 1,024. The page takes the stricter: a KB is 1,000 bytes and an MB 1,000,000, so a file made for "under 200 KB" is at most 200,000 bytes and passes either way.

Private

The PDF never leaves your device. It is rewritten by qpdf, drawn by pdf.js and rebuilt by pdf-lib, all running in your browser. A file locked only against editing is opened as it is; one that needs a password to open needs unlocking first, with protect and unlock PDF. For a photo or signature that has to be a certain size, use resize photo to KB; to cut a long PDF into parts that each fit, split PDF.

questions

How do I compress a PDF to 200 KB?

Choose the PDF, pick under 200 KB, and press Compress. The page tries the gentlest change first: if the file is already under, it is kept as it is; if rewriting it smaller gets it under, that is done with the text left as text; only if neither is enough is each page saved as a picture, at the best resolution and quality that fit. Then download the PDF.

Will the text still be selectable?

If the file can be got under the limit by rewriting it — recompressing its streams and re-encoding any photos inside — yes, the text stays text. When it has to go further, each page becomes a picture: the words are still there to read, a little softer, but they can no longer be selected, searched or copied. Switch on keep text copyable and searchable to rule that out; the page then says how small it could get without it.

How small can it go?

It depends on the pages. Turned into pictures, a page of plain text at the lowest setting is a few kilobytes, and a full-colour photo page more. The page tries resolutions from 150 down to 50 dots per inch and JPEG qualities from 85% down to 25%, choosing the clearest result that fits and preferring a lower resolution to blocky compression. Greyscale pages help a lot with scans of text. Up to 80 pages can be drawn as pictures in a browser; split a longer file first. If even the smallest is over the limit, the page says how small it got.

Why is the file a little under the limit, not on it?

Forms count a KB as 1,000 or 1,024 bytes, and rarely say which. The page takes a KB as 1,000 bytes and an MB as 1,000,000, the stricter reading, so the file passes either way.

Can it compress a password-protected PDF?

A PDF that opens without a password but is locked against editing, as many bank statements are, is opened and compressed as it is; the copy does not carry the lock. One that needs a password to open has to be unlocked first with the PDF protect and unlock tool, which also runs in your browser.

Is my PDF uploaded?

No. The file is read, rewritten and drawn by your browser, using qpdf, pdf.js and pdf-lib running in the page. Nothing is uploaded, stored or sent anywhere.