BYTETOOLS

Compress PDF

Reduce PDF file size in your browser by re-encoding pages as JPEG at a quality you choose. Free PDF compressor with no upload and no watermark.

Drop a PDF here or click to browsePages are re-rendered as JPEG images — text stops being selectable

What is the Compress PDF?

The ByteTools PDF Compressor shrinks oversized PDFs so they fit inside email limits and upload forms.

  • Quality slider and DPI control for precise size targeting
  • Shows original size, new size and the percentage saved
  • Works on scans, brochures and image-heavy reports
  • 100% local — the PDF is never uploaded anywhere
  • No watermark, no page limit and no sign-up
  • Warns you when a file cannot be made smaller

How to use the Compress PDF

  1. 1

    Drop your PDF onto the upload area to see its current file size.

  2. 2

    Set the JPEG quality slider — 60 to 75 works well for scanned documents.

  3. 3

    Choose an output resolution; lower DPI produces the smallest files.

  4. 4

    Click Compress PDF and compare the before and after sizes.

  5. 5

    Download the compressed file, keeping the original as a backup.

About the Compress PDF

The ByteTools PDF Compressor shrinks oversized PDFs so they fit inside email limits and upload forms. Each page is redrawn as a JPEG image at the quality and resolution you pick, then rebuilt into a new PDF — you see the before and after sizes before you download anything.

Compression runs entirely inside your browser using JavaScript. The document is never uploaded to a server, so invoices, scanned contracts, passports and internal reports stay on your own machine from the moment you drop them in.

This is lossy compression, and it is worth being clear about the trade-off: because pages become images, text stops being selectable or searchable and fine detail softens as quality drops. That is exactly what makes it so effective on scan-heavy files, and why you should keep the original.

Frequently asked questions

How do I reduce the size of a PDF without losing too much quality?

Start at 70% quality and 110 DPI, then check the result. If the file is still too big, drop the resolution before you drop the quality — halving DPI removes far more bytes than a few quality points, and text usually stays readable down to about 100 DPI.

Why did my PDF barely get smaller?

Files that are mostly vector text are already very compact, so turning them into images can even make them larger. This compressor shines on scans and photo-heavy documents. If the tool reports little or no saving, keep your original file.

Does compressing a PDF make the text unselectable?

Yes. Every page is rasterised into a JPEG, so the finished PDF contains pictures rather than characters. You can still read and print it, but you cannot select, search or copy the text, and screen readers will not see it.

Is it safe to compress a confidential PDF online?

With this tool, yes. The rendering and rebuilding happen in your browser with JavaScript, and nothing is transmitted to a server. You can load the page, go offline, and still compress the file.

What is a good PDF size for email attachments?

Most mail providers accept attachments up to 20–25 MB, but many corporate gateways cut that to 10 MB. Aiming for under 5 MB keeps a document deliverable almost everywhere and quick to open on a phone.

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