What is the Compress PDF?
Most of a large PDF’s size is usually photos and scanned pages stored at far higher resolution than a screen or printer needs. Compress PDF re-saves those images at a sensible size and quality, while text, lines and fonts are left exactly as they were, so the document stays sharp and searchable.
For scanned documents that must fit a strict limit, such as a 1 MB or 500 KB upload on a government or exam portal, the “Pages to images” option renders each page as a compressed picture, which usually gives the smallest file. You always see the size before and after, and if a file cannot be made meaningfully smaller, the tool says so instead of giving you a bigger file.
How to use it
- Drop a PDF on the box, or click to choose one.
- Choose a compression level. Recommended suits most files.
- For scans that must be very small, tick “Pages to images” and pick a resolution.
- Click Compress PDF and download the smaller file.
Features
- Keeps text sharp. Only images are recompressed; text and vector graphics are untouched.
- Three levels plus custom. Light, Recommended or Strong, or set image quality and size yourself.
- Pages to images. Maximum compression for scans, at a resolution you choose.
- Honest results. Before and after sizes, and no download when there is nothing worth saving.
- Safe for images it cannot handle. CMYK, masked and unusual images are kept exactly as they are.
- Private. Compression runs in your browser; your PDF is never uploaded.
Frequently asked questions
How much smaller will my PDF get?
It depends on what is inside. PDFs full of photos or scans often shrink by 50–90%. PDFs that are mostly text are already small and may hardly change.
How do I get a PDF under 1 MB or 500 KB?
Start with Strong. If it is still too big and the PDF is a scan, tick “Pages to images” and try 150 DPI, then 120 or 100 DPI. Lower resolution means a smaller file but softer text.
Will the text still be selectable?
Yes with the normal levels. With “Pages to images”, each page becomes a picture, so text can no longer be selected or searched.
Why did my PDF not get smaller?
It may contain no large images, or its images may already be well compressed or of a type that cannot be safely changed (such as CMYK print images). Try Strong, or “Pages to images” for scans.
Does compression affect a password-protected PDF?
You enter the password to open it, and the compressed copy is protected with the same password.
Is my file uploaded to a server?
No. The PDF is compressed on your device.
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