PDF Compressor
Reduce and optimize PDF file sizes privately in your browser. Choose compression presets for email sharing and web storage.
Choose a PDF File or Drag & Drop Here
Strict File Limit: Up to 50MB (Client-Side Compression Engine)
Choosing a Compression Level That Fits the Document
This compressor works by rendering each page of your PDF and re-encoding it as a JPEG image, then assembling those images into a new PDF. That approach explains both its strength and its main trade-off, so it helps to know what to expect before you pick a preset.
What the three presets actually change
Each preset pairs a render scale with a JPEG quality setting. Extreme uses about 50% quality at 1.0x scale, Recommended uses about 72% at 1.25x, and Low Compression uses about 88% at 1.5x. Lower quality and a smaller render scale both shrink the file, but they also soften fine detail. Small body text and thin table rules are the first things to suffer.
Which preset to try first
- Email attachments: start with Recommended. If the result is still over your mail limit, rerun the original file on Extreme rather than compressing the already-compressed output again.
- Scanned documents: these are already page-sized images, so Extreme often gives the biggest drop with acceptable readability.
- Slide decks and photo-heavy reports: use Low Compression and check gradients and faces afterward.
- Documents you plan to print: Low Compression is the safer choice, since print exposes softness that a screen hides.
Things to check before you send the result
Because pages become images, text in the output may no longer be selectable or searchable, and links or form fields will not carry over. Keep your original for anything that needs copy-and-paste, accessibility, or editing. Open the compressed file and zoom to 100% on a page with small print before you share it.
Text-only PDFs exported from a word processor are often small already. Converting them to images can make the file larger, not smaller. If the saved percentage shows little or negative gain, simply keep the original.
If the tool struggles
Files above 50MB are rejected to protect browser memory. For a long document near that limit, split it first with the PDF Splitter, compress each part, and combine them again with the PDF Merger. Closing other heavy browser tabs also helps on phones and older laptops.
Compression time grows with page count, since every page is rendered one at a time. A progress bar shows where it stands, so a slow run on a 200-page file is normal rather than a freeze.
Compare before you replace
Save the compressed file under a different name and compare both versions side by side on the pages that matter most. If the saved percentage is small and quality dropped, the smaller preset was not worth it, and one step up the ladder usually settles the question.
Frequently Asked Questions
Is my PDF uploaded to a server?
No. The page states that compression runs in your browser, so the document stays on your device. Pages are rendered and re-encoded locally. Closing the tab ends the process, and nothing needs to be installed to use it.
What does the Saved percentage mean?
After compression the tool shows the original size, the compressed size, and the percentage of file size saved. It is a simple comparison of those two figures. A low or negative result means the new file is not meaningfully smaller than the original.
Does compressing change my original file?
No. The tool produces a new compressed PDF for you to download, and the file you selected stays as it was on your device. Use Compress Another PDF to start over with a different file.
Can I compress several PDFs at once?
The tool works on one PDF at a time. You select a single file, choose a compression level, and download the result. To handle more documents, use Compress Another PDF after each download and repeat the steps for the next file.