PDFalo
Compress PDF
Reduce the size of a large PDF so it is easy to email or upload. Your file stays on your device.
- 100% private
- Free forever
- No sign-up
Drop a PDF file here
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Note: compressing turns each page into an image, so text can no longer be selected or searched.
Your file is ready
DownloadHow to compress a PDF online
- Click Choose PDF file or drag a PDF into the box.
- Choose a compression level: Light keeps the best quality, Medium is balanced, and Strong gives the smallest file.
- Click Compress PDF. The tool shows its progress page by page.
- Download the new file. The page shows the old size, the new size and how much smaller it is.
How this tool compresses
To make the file smaller, each page is drawn as a picture and saved as a compressed JPEG image. A lower level reduces the picture's sharpness and quality more, which is what makes the file smaller. This works very well for scanned documents and PDFs full of photos, because those files already consist of large images.
An important limitation
Because pages become pictures, the text in the compressed file can no longer be selected, copied or searched. If you need searchable text, keep the original file as well. PDFs that contain mostly text are already small, so they often cannot be reduced much, and in that case the tool tells you instead of giving you a bigger file.
Which level should you choose?
- Light: for documents that will be printed or read closely, where you want to keep detail.
- Medium: a good starting point for email attachments and online forms.
- Strong: when a website or email limit is strict and quality matters less, such as a rough scan of a bill.
If the first result is still too large, run the original file again with a stronger level. Compressing an already compressed file repeatedly lowers quality more each time, so always start from the original.
Common upload limits
Many job portals, government forms and email services limit attachments to a few megabytes. Compress the PDF, check its size, and upload the smaller version. If you have several files, you can merge them first and compress the combined file afterwards.
Privacy
Compression runs inside your browser. Your PDF is not uploaded, and the smaller file is created on your own device.
Frequently asked questions
Why can I not select text after compressing?
Each page is saved as an image to reduce the size. Keep the original file if you need searchable text.
Why did the tool say my PDF is already small?
If the compressed version would not be smaller than the original, the tool does not offer it. Try the Strong level or keep the original.
Is there a file size limit?
There is no fixed limit, but large files take longer and depend on your device's memory.
Will my file be uploaded anywhere?
No. All the work happens in your browser on your own device.
Can I compress a password-protected PDF?
No. Remove the password first, then compress the unlocked copy.