How much can PDF compression reduce file size?

It depends on what's in your PDF. Scanned or photo-based documents typically drop by 80-90% with the 'Smallest file' option. Text documents and fillable forms often drop by around a third with 'Keep text selectable', purely from repacking the file. Some PDFs are already lean and cannot be meaningfully reduced by any tool — when that's the case we say so rather than hand you a download that changed nothing.

Will compression affect text readability?

With 'Keep text selectable', no — that option is lossless and rewrites no image or text data at all, so your document is character-for-character identical. With 'Smallest file', each page becomes a picture: it still looks right, but the text can no longer be selected or searched.

Is my PDF uploaded to a server for compression?

No. Everything runs in your browser using WebAssembly. Your file never leaves your device — it's compressed on your own hardware.

Can I choose how much the file is compressed?

You choose between two options. 'Keep text selectable' repacks the file without altering a single pixel, so nothing is degraded and your text stays searchable. 'Smallest file' turns each page into a picture, which typically removes 80-90% from a scan but means the text can no longer be selected. The tool pre-selects whichever suits your file.

Will compression make my images look blurry?

Not with 'Keep text selectable' — that option is lossless and changes no image data at all. 'Smallest file' redraws pages at screen resolution, so fine detail softens slightly; it is intended for scans, where that trade is usually worth an 80-90% size reduction.

My PDF is a locked bank statement or payslip. Will it work?

Yes. Some PDFs are marked read-only by whatever produced them, even though they open normally everywhere else. The tool detects that and unlocks it automatically, on your device, then compresses as usual. A PDF that genuinely needs a password to open is the one exception — open it in your reader, save an unlocked copy, and compress that.

Can I compress the same file more than once?

You can, but returns diminish quickly — most of the savings come from the first pass. If a second pass can't achieve anything worthwhile, the tool tells you and gives you nothing to download.

My compressed scan is no longer searchable. Can I get the text back?

Yes, and it is expected rather than a fault. The 'Smallest file' option turns each page into a picture, which is what buys the 80-90% saving, but a picture of a word is not a word, so searching and selecting stop working. Getting real text back needs OCR, which reads the words off the page and writes them into the file as text. That takes more processing than a browser tab can do, so it runs in our sister app PDF Cubby. Compressing first and running OCR afterwards gives a small file that is still searchable.

Is the compress tool free, and do I need an account?

Compressing PDFs is completely free and unlimited, with no watermark and no sign-up required. Every tool on the site is free.

Compress PDF Online — Reduce File Size Locally for Free

Shrinking a PDF shouldn't mean handing it to a stranger's server. SecurePDFSuite compresses your file entirely inside your browser — on your own device, never uploaded. Scans and photo-heavy PDFs typically drop by 80–90%; documents and forms can be repacked losslessly, leaving every character and form field exactly as it was. It's the easy way to get a bulky report or scan under an email attachment limit without the privacy trade-off.

How to compress PDF files

Upload your PDF Select the PDF file you want to reduce in size.
Choose how to compress Pick Keep text selectable for documents and forms, or Smallest file for scans and photos — we inspect your PDF and pre-select the right one.
Compress locally Click Compress — the work happens inside your browser, with no server upload. If your PDF can't be made meaningfully smaller, we say so rather than hand you a pointless download.
Download the smaller PDF Save the compressed PDF. Compare the file sizes and re-compress if you need it smaller.

When to compress a PDF

A too-big PDF gets in the way constantly. Compression is the fix when you need to:

Get a file under an email attachment limit (often 20–25 MB)
Shrink an image-heavy scan or brochure for faster sharing
Reduce a portfolio or catalog before uploading it to a web form
Save storage space when archiving lots of documents
Speed up how quickly a PDF loads on a website
Trim a merged file that came out larger than expected

Why compress PDFs in your browser instead of uploading

Most online compressors upload your document to their servers, run the optimization there, and hand you back a link. For a file you were only trying to make smaller, that's an unnecessary round trip through infrastructure you don't control.

SecurePDFSuite compresses locally with WebAssembly, right inside your browser tab. Your file never crosses the internet, so nothing is exposed in transit and nothing is retained after you close the tab.

That keeps even routine housekeeping private for sensitive material — legal files, medical records, financial statements, or anything you'd rather not upload just to save a few megabytes.

Features

Two clear options, not a menu of guesses — keep your text selectable, or go for the smallest possible file
We pick for you — the tool inspects your PDF and pre-selects the option that suits it
A genuinely lossless option — "Keep text selectable" repacks the file without altering a single pixel
Big wins on scans — "Smallest file" typically removes 80–90% from a scanned document
We never hand back a bigger file — and if your PDF is already lean, we say so instead of giving you a pointless download
Locked files just work — read-only statements and payroll PDFs are unlocked automatically
100% local processing — the file is compressed on your own hardware
No watermark and no sign-up required

Tips for best results

Scans and photos compress most — a scanned document usually drops by 80–90%
Forms and text documents still gain — a heavy fillable form often drops by around a third, with every field and character intact
Already small and lean? No tool can do much, and we would rather tell you that than pretend
Just combined several files? Compress after you Merge PDF
Used Smallpdf for this before? The two differ mainly in where your file actually goes — see SecurePDFSuite vs Smallpdf

Frequently Asked Questions

How much can PDF compression reduce file size?: It depends on what's in your PDF. Scanned or photo-based documents typically drop by 80–90% with the "Smallest file" option. Text documents and fillable forms often drop by around a third with "Keep text selectable", purely from repacking the file. Some PDFs are already lean and cannot be meaningfully reduced by any tool — when that's the case we tell you rather than hand you a download that changed nothing.
Will compression affect text readability?: With "Keep text selectable", no — that option is lossless and rewrites no image or text data whatsoever, so your document is character-for-character identical. With "Smallest file", each page becomes a picture: it still looks right, but the text can no longer be selected or searched. That option is meant for scans, which have no selectable text to lose in the first place.
Is my PDF uploaded to a server for compression?: No. Everything runs in your browser using WebAssembly. Your file never leaves your device — it's compressed on your own hardware.
Can I choose how much the file is compressed?: You choose between two options rather than a scale. "Keep text selectable" is lossless and keeps your document exactly as it is. "Smallest file" goes as small as possible by turning pages into pictures. The tool inspects your PDF and pre-selects the one that suits it, and you can switch.
Will compression make my images look blurry?: "Keep text selectable" cannot — it changes no image data at all. "Smallest file" redraws each page at screen resolution, so fine detail softens a little; it's chosen to stay comfortably readable and is intended for scans, where it typically saves 80–90%.
My PDF is a locked bank statement or payslip. Will it work?: Yes. Some PDFs are marked read-only by whatever produced them, even though they open normally everywhere else. The tool detects that and unlocks it automatically, on your device, then compresses as usual. A PDF that genuinely needs a password to open is the one exception — open it in your reader, save an unlocked copy, and compress that.
Can I compress the same file more than once?: You can, but returns diminish quickly — most of the savings come from the first pass. If a second pass can't achieve anything worthwhile, the tool will tell you and give you nothing to download.
My compressed scan is no longer searchable. Can I get the text back?: Yes, and this is expected rather than a fault. The Smallest file option works by turning each page into a picture, which is what buys you the 80–90% saving — but a picture of a word is not a word, so searching and selecting stop working. To get real text back you need OCR, which reads the words off the page and writes them into the file as text. That takes more processing than a browser tab can do, so it runs in our sister app: PDF Cubby will OCR the scan. Doing it in that order — compress, then OCR — gives you a small file that is still searchable.
Is the compress tool free, and do I need an account?: Compressing PDFs is completely free and unlimited, with no watermark and no sign-up required. Every tool on the site is free.

Compress PDF Files Online