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PDF Editor

Compress a PDF

Reduce file size by rasterising pages at a DPI and JPEG quality you choose. Best for scans and image-heavy decks.

  • Free, no signup
  • No upload — runs on your device
  • No watermark
  • Unlimited use

Compress PDF

Processed locally
Drop a PDF here

or click to browse

Lower means smaller and blurrier.

This is lossy compression, and you should know what you are trading

Most "PDF compressors" do one of two very different things. The gentle kind re-samples embedded images and strips unused objects, leaving text as text. The aggressive kind — this one — renders every page to a bitmap and rebuilds the PDF from those images. The second approach reliably hits a size target; it also destroys selectable text, kills accessibility for screen readers, and makes the document unsearchable.

That trade is correct for a scanned contract, a photo-heavy portfolio, or anything you just need to get past a 10 MB mail gateway. It is the wrong call for a report someone will Ctrl-F through. Rule of thumb: 150 DPI at 70% quality is the sweet spot for on-screen reading and typically cuts a scan by 70–90%. Drop to 96 DPI only if the recipient will never zoom in. Stay at 300 DPI if it will be printed.

How it works

  1. Drop in the PDF you want to shrink
  2. Set the DPI and JPEG quality — 150 DPI at 70% is a good default
  3. Click Compress and check the reported size reduction
Why nothing uploads. Every operation on this page happens inside your browser using JavaScript and WebAssembly. Your file is read into memory, processed, and offered back as a download. It is never transmitted. Disconnect from the internet after this page loads and the tool keeps working.

Frequently asked questions

Why did compression make my text-based PDF larger?
Because this tool converts pages to images. A page of crisp vector text may occupy 8 KB as text but 200 KB as a JPEG. If your PDF is mostly text and already small, compression will not help — the source is already efficient.
What DPI should I use to email a document?
150 DPI at 70% quality reads well on any screen and usually clears a 10 MB limit comfortably. Use 96 DPI for the smallest possible file when print quality is irrelevant. Never go below 150 DPI for anything containing small type.
Will the text still be searchable after compressing?
No. Rasterisation replaces text with pixels. If searchability matters, keep the original and send the compressed copy only as a preview, or use OCR software on the output to re-add a text layer.
How much smaller will my file get?
Scanned documents typically shrink 70–90%. Image-heavy presentations shrink 50–80%. Vector-only text documents may grow. The tool reports the before-and-after size so you can check before sending.
Can I compress a PDF without losing any quality at all?
Not meaningfully in a browser. Truly lossless PDF optimisation requires deduplicating fonts and object streams, which needs a full PDF rewriter. If you cannot accept quality loss, remove unnecessary pages or images instead — try the Delete PDF Pages tool.

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