masstree.inCompress PDF
Make any PDF smaller right here in your browser. Choose a quality, or set a target size in KB and the tool finds the best quality that fits.
Runs in your browser — nothing is uploaded or stored on a server.
How to split
Pages to remove
Rotation
Numbering
Compression
Pages are redrawn as images, so text stops being selectable. Keep the original if you need to search it later. With a target size, quality and resolution are lowered step by step until the file fits.
Output
Page size
Watermark
Your signature
Placement
This is a visual signature placed on the page, the same as signing a printout — not a cryptographic certificate.
Output
Only the text is kept, in paragraphs with a page break between pages. Scanned PDFs have no text — turn them into images and let the assistant read them.
Working…
How to compress a PDF
Drop the file on the box above, pick a quality and resolution, and press Compress. The new file downloads straight away with the size shown next to it. If a portal asks for a limit such as 200 KB, type it in the Target size box and the tool works down to that size on its own.
How it works
Each page is redrawn as a JPEG at the quality you choose, then the pages are rebuilt into a new PDF. Scans and photos shrink the most; a PDF that is mostly text is already small, so it changes little.
Tips for a smaller file
Scan text documents in greyscale, crop blank margins before scanning, and remove pages you don't need with the Remove pages tab first. For printing keep the Large setting; for e-mail and uploads Medium or Small is enough.
Questions
How much smaller will my PDF get?
Scanned and photo-heavy PDFs usually shrink by 60–90%. PDFs that are mostly text are already small and change little; use a target size if a form needs an exact limit.
Is my PDF uploaded anywhere?
No. The compression runs inside your browser with pdf.js and pdf-lib; nothing is sent to masstree.in or any other server, so it also works offline once the page has loaded.
Can I compress to an exact size like 200 KB?
Yes. Type the size in the Target size box, or use the 100 KB, 200 KB, 500 KB and 1 MB buttons. The tool lowers quality and resolution step by step until the file fits.
Will the text still be selectable?
No. Pages are redrawn as images to reduce the size, so the result behaves like a scan. Keep your original if you need to copy or search the text later.
Is there a file size or page limit?
There is no fixed limit. Everything happens on your device, so very large files simply take longer; a 50-page phone scan takes about a minute on a mid-range phone.