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SlimMyFile

Compress PDF files online

Reduce the size of your PDF directly in your browser. Text stays searchable, links keep working and your document is never uploaded.

Processing happens in your browser. Files are never uploaded to a server.

Drop your file here

or

PDF · up to 150 MB each

Files are opened locally and never uploaded.

How to use this tool

  1. 1Select or drop a PDF file.
  2. 2Read any notes about signatures, forms or scanned pages.
  3. 3Choose Low, Balanced or High compression.
  4. 4Click Compress PDF, check the real result, then download.

Supported formats

Input
PDF (not password-protected)
Output
PDF

Features

  • Three levels, from lossless clean-up to strong photo compression
  • Text stays searchable, vectors stay sharp and links keep working
  • Optional scanned document mode with resolution and quality controls
  • Every output is checked for integrity before you can download it
  • Your original is offered when no useful reduction is possible

A free PDF compressor that keeps your document private

Most online PDF compressors send your file to a remote server. SlimMyFile works differently: the optimisation engine is downloaded to your browser and runs on your own device. Contracts, invoices, medical letters and ID scans stay with you.

How we reduce PDF file size

SlimMyFile combines several real techniques, and only keeps a change when it actually makes the file smaller:

  • Re-encoding oversized embedded photos with MozJPEG and limiting their resolution (Balanced and High).
  • Recompressing internal data streams at maximum Flate compression (all levels).
  • Removing unreachable objects left behind by edits, plus page thumbnails and application private data.
  • Packing objects into compressed object streams.

What to expect

Results depend entirely on the document. PDFs exported from phones, scanners or design tools with high-resolution photos can often shrink a lot. A text-only PDF made by a word processor is usually already compact, and we will tell you honestly when no useful reduction is possible.

For scanned documents, the optional scanned document mode re-renders each page as a compressed image. It can give large savings but removes searchable text, links and form fields, so it is never applied without your explicit confirmation.

Your privacy

Files are read and processed by your browser on this device. They are not uploaded, stored or shared, and closing the page discards them. Processing speed and the largest file you can handle depend on your device.

Frequently asked questions

Will my PDF still be searchable after compression?

Yes, in Low, Balanced and High modes. Only embedded images are changed; text, fonts and vector graphics are kept. The optional scanned document mode is the exception and is clearly labelled.

Why did my PDF barely get smaller?

If a PDF contains mostly text and vector graphics, or its images are already compressed, there is little left to remove. Browser-based tools also cannot subset fonts, which desktop tools sometimes do.

Can I compress a password-protected PDF?

No. Encrypted PDFs cannot be modified without the password, and we do not try to bypass protection. Remove the password in an app you trust first.