Don's Tools · PDF · Compress PDF

Compress PDFs

Shrink up to 500 PDFs at once, right in your browser. Big savings on scans and photos, a lossless option for text, and never larger than you started. Nothing is uploaded.

Mode
Compression
65%

Keep text re-saves your PDFs and strips unused data without changing how they look. Text stays selectable. Savings are usually small and depend on the file.

Drop PDFs here
or tap to choose · up to 500 at once · your files stay on your device
Your PDFs will appear here
Compress PDF is a free batch tool to reduce the size of up to 500 PDFs entirely in your browser. Choose Recompress images to re-render pages as compressed images for large savings on scanned and image-heavy PDFs, or Keep text to losslessly slim text PDFs while keeping text selectable. Adjust quality and resolution, optionally convert to grayscale, see each file before and after, download files one by one or all together as a zip, and the result is never larger than the original. Your PDFs are never uploaded and stay on your device.

Files are processed in your browser and never uploaded.

How to use Compress PDFs

  1. Add your files

    Drop up to 500 PDF files onto the upload area, or tap the area to choose them from your device.

  2. Set the options

    Choose Quality, Resolution and Grayscale. Every setting is on screen before you add a file, so you can see what the tool will do before it runs.

  3. Run it and save

    Press Compress it, Don →. The button stays disabled until there is something to work on, and each file shows its own progress and result. Press Download all, Don (.zip). Each finished file keeps a name based on the one you started with, so you can tell the versions apart.

What this tool does

Compress up to 500 PDFs at once

Drop up to 500 PDFs at once and each is compressed in turn on your device, with its own before and after size shown next to it.

Recompress images mode for scans and photos

Recompress images re-renders each page as a compressed image, which is what gives scans and photo-heavy PDFs the big savings.

Lossless keep-text mode

Keep text leaves the text and vectors untouched and strips only the overhead, so a document that is mostly type stays perfectly sharp.

Adjustable quality and resolution

Compression has Max shrink, Balanced and High quality presets, with a quality slider and a resolution from 72 up to 150 dpi behind them.

Optional grayscale

Grayscale drops the colour, which is worth a lot on a scanned document that was black and white to begin with.

Never larger than the original

If a setting would make a file bigger than it started, the original is kept instead, so you can never come out worse than you went in.

Frequently asked questions

How many PDFs can I compress at once?

Up to 500 per batch. Everything runs on your device, so a big batch depends on your computer's memory and speed. On older phones or low-memory devices, very large or very many PDFs may slow down, so just do them in smaller groups.

Are my PDFs uploaded anywhere?

No. Every PDF is opened and compressed inside your browser on your device, and nothing is ever sent to a server.

How much smaller will my PDFs get?

It depends what is inside. Scanned or image-heavy PDFs often drop by around 40 to 70 percent, while mostly-text PDFs only shrink a little. If a file is already well optimised, the tool keeps the original so the result never ends up larger.

What is the difference between the two modes?

Recompress images re-renders each page as a compressed image, which gives big savings on scans and photos but turns the text into part of the image so it is no longer selectable. Keep text re-saves the file and strips unused data losslessly, so the text stays selectable but the savings are smaller.

Will the quality drop?

In Recompress mode you control it with the Quality slider and Resolution, where lower settings mean a smaller file and softer images. Keep text mode is lossless and does not change how anything looks.

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