Compress a PDF
Lighten PDFs that are too heavy to email: a lossless optimisation that keeps the text, or a stronger compression that rasterises the pages into images, with the weight before and after shown. When the size is the only problem, a lossless pass often halves a scanned document. The processing happens on your device, so a document you compress never leaves your machine.
- 100% local
- Free · no account
- Instant result
This tool runs entirely in your browser — nothing is sent to a server.
A PDF too heavy to send by e-mail is almost always heavy because of its images: a high-resolution scanned document easily weighs several dozen megabytes, while a pure-text PDF rarely exceeds a few hundred kilobytes.
This tool therefore offers two very different strategies, and it matters to choose the right one. Lossless optimisation rewrites the file’s internal structure: the gain is modest, sometimes nil if the PDF is already optimised, but the text stays intact and selectable. Rasterisation converts each page into a JPEG image at the resolution you choose: the gain is spectacular on scanned documents, at the price of losing selectable text.
How it works
Type the figures or drop the file you want to process — the tool checks them as you go.
Everything is computed directly in your browser. Nothing is sent to a server.
The result appears instantly, with the detailed breakdown ready to copy, download or keep.
Why use this tool
No account, no download, no limit: the result appears as soon as you enter your data.
Every rule, algorithm and check reflects what we use ourselves every day at Flexina.
The calculations follow the official standards, and the step-by-step detail lets you double-check the outcome.
What does running it locally bring you?
Files, figures and documents never leave your device: nothing is stored, nothing is sent.
Once the page is loaded, you can cut the network: the tool keeps working.
No upload, no account, no third-party server in between: results stay fast and fully private.
Frequently asked questions
Which mode should I choose?
If your PDF contains text you want to select, search or copy, stay on lossless optimisation. If your PDF is a scanned document and only the weight matters, rasterisation will often divide its weight by five or ten.
Why is the gain sometimes nil, or even negative?
A well-optimised PDF has little left to gain in lossless mode. In rasterisation, a pure-text document can even become heavier, because very light vector text is replaced by images. The tool warns you in that case and suggests keeping the original.
What exactly is lost when rasterising?
The text becomes an image: no more selecting, copy-paste or search, and the document becomes inaccessible to screen readers. Clickable links, bookmarks and form fields also disappear.
Is my document sent to a server?
No. The compression is performed entirely in your browser, which makes it usable for confidential documents.