Compress PDF

Compress PDF online, free. Choose lossless, smart or strong compression and compare sizes. Local processing — files never leave your device.

Compress PDF reduces file size with minimal impact on readability — ideal for email attachments, web uploads and any channel with a size limit.

Three strategies are available: Light (lossless) restructures the file without touching image quality, while Smart and Strong re-encode page images at a chosen quality for higher compression. Before-and-after sizes are displayed so you decide whether to keep the result.

Everything runs locally in your browser — nothing is uploaded to any server, so confidential documents can be compressed safely.

How to use

  1. Pick the PDF — Drop in or select a file — it is read locally, with no upload wait.
  2. Choose a level — Use Light for official documents, Smart or Strong when you need a much smaller attachment.
  3. Adjust quality — The lossy levels expose an image-quality slider: lower quality means a smaller file.
  4. Compare and download — Review the before/after sizes and savings, then download only if you are happy.

Use cases

FAQ

Will compression hurt quality?

It depends on the level. Light is a lossless rewrite with zero quality loss; Smart and Strong re-encode page images — usually imperceptible on screen, but visible when zoomed in or printed at high quality.

Why does my PDF barely shrink?

Text and vector PDFs are already efficiently encoded and have little room left. That is normal — retrying will not help.

Can compression be undone?

Lossy compression is irreversible. Keep the original file and re-process from it whenever you need higher quality.

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