How to Compress a PDF for Free (Reduce File Size)
3 min read
Scanned documents and image-heavy PDFs can balloon to 10, 20, even 50 MB - too big for email attachments or upload forms that cap at 5 MB. The good news: you can shrink a PDF in seconds without any software or sign-up.
Here is how to compress a PDF for free, right in your browser, so the file never leaves your device.
Step by step
- 1Open the compressor
Go to the Compress PDF tool and choose the PDF you want to shrink. It loads locally - nothing is uploaded.
- 2Pick a compression level
Choose how hard to compress. A lighter setting keeps more quality; a stronger setting makes the smallest file. For email and forms, the medium or strong setting usually does the job.
- 3Compress and preview the new size
Run the compression and check the new file size against the original so you know how much you saved.
- 4Download your smaller PDF
Save the compressed file. It is ready to email, upload, or store.
Tips
- Most savings come from images - a PDF that is mostly text is already small and will not shrink much.
- Strong compression re-saves the pages as optimized images, so selectable text in a scan becomes a picture. Keep your original if you might need to edit or copy text later.
- Gmail allows attachments up to 25 MB, but many government and job-application forms cap at 5 MB, so compress to be safe.
Frequently asked questions
Will compressing reduce the quality?
It can, slightly - you choose the level, trading a little image quality for a much smaller file. Text-based PDFs stay crisp.
Is my PDF uploaded anywhere?
No. The compression runs entirely in your browser, so your document is never sent to a server or stored.
Why is my PDF still large after compressing?
If it is mostly text rather than images, it was already efficient. The biggest reductions come from PDFs full of photos or scanned pages.