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Compress PDF
Reduce file size for sharing. Free, no sign-up.
or drop it here
Compress PDF runs inside your browser — your file never reaches our servers.
How to compress PDF
Compression tries two approaches and keeps whichever is smaller — and never returns a file bigger than the one you started with.
- Select your PDF. Scans and image-heavy documents shrink the most.
- Choose how hard to squeeze. Light keeps text crisp; Strongest is for getting under a size limit.
- Download. You are shown exactly how much smaller it got.
The numbers behind each level
The lossless attempt reloads the document and rewrites its objects into object streams. Nothing is re-encoded, so text stays vector text and links, form fields and bookmarks survive; the saving is only whatever the tighter structure buys. The raster attempt rebuilds every page as a JPEG at a fixed resolution and quality: Light at 150 dpi and quality 0.72, Balanced at 110 dpi and 0.60, Strongest at 72 dpi and 0.50.
That is why results vary so wildly between files. A scan photographed at 300 dpi carries roughly seven times the pixels Balanced keeps, so it usually loses most of its size. A text-and-vector report has almost nothing to remove and its raster attempt comes out larger than the original, so the repacked version wins — and where even that is no smaller, your original bytes come back untouched. The note under the result gives the before and after sizes, or says the original was kept.
How to tell which route your file took
Open the result and try to select a line of text. If you can, the lossless repack won and nothing was re-rendered. If you cannot, the raster route won: every page is now a picture of itself — the same rendering PDF to JPG does — wrapped back into a PDF, so links, bookmarks, annotations and form fields have gone with the text layer. Page dimensions, orientation and page count are preserved either way, and a rotated page is baked upright into its image.
Nothing here re-encodes individual image streams or subsets fonts the way a file-level optimiser does; it either keeps everything losslessly or rebuilds the pages. That is also why there is no target-size box: pick a level, read the number, and step down if it is not enough. When the ceiling is an email attachment limit, Split PDF is often kinder to the document than crushing it.
Questions
Why did my file barely shrink?
Text-and-vector PDFs are already efficient — there is little to remove, and rasterising them would blur the text while making the file bigger. In that case we keep the lossless version instead of damaging your document to hit a number. Scans, which are images, shrink dramatically.
Will the text still be selectable?
With Light and Balanced on a text PDF, yes. Strongest on an image-heavy file may rebuild pages as images, which removes the text layer — run OCR PDF afterwards to put a searchable layer back.
Can I compress to a specific size, such as under 10 MB?
Not directly — there is no target-size setting. Pick a level, read the before-and-after figure under the result, and step down a level if it is still too big. If the limit is an email attachment cap, splitting the document into two files is often better than compressing it further.
Does compressing change the page size or the page count?
No. Dimensions, orientation and the number of pages are preserved exactly, even when the pages are rebuilt as images, and a rotated page still opens the right way up. Only the resolution of what is drawn on those pages changes.
Is it worth running compression twice?
Rarely. A second pass re-renders pages that are already soft, so you lose more detail for a small extra saving — and if neither route beats the file you fed in, the same file comes back. Going straight to a stronger level achieves more than repeating a weaker one.
Are my files uploaded to a server?
No. Every tool on this site runs inside your browser, using the same engine as the Folia desktop app. Your file is read from your disk into your browser’s memory, processed there, and handed back as a download. It never crosses the internet, so there is nothing for us to store, leak or hand over.
Is there a file size limit?
We impose none. The only ceiling is your own device’s memory, which differs from one computer to another — so we read what your browser reports about this machine and show the resulting limit on the page. Light tools like merge and rotate handle far more than heavy ones like OCR, which must render every page. For anything larger, Folia for Desktop has no limit at all.
Is it really free? Do I need an account?
Yes, and no. Every tool is free and unlimited, with no watermark and no sign-up. Ads pay for the site, and your own computer does the work, which costs us nothing. Signing in with a paid Folia plan simply removes the ads.