Compress PDF online — reduce file size, free
Shrink PDFs for email, upload, or storage. Pick a quality level, see exactly how much smaller the file becomes, and download. Your PDF never leaves your browser.
Everything in this PDF compressor
A free, fast, private compressor for everyday use — no signup, no watermark, no upload.
Three quality levels
Choose High quality to preserve text, or Recommended for image-based compression. Compare the result with your original.
See sizes before & after
We show the original file size, the new compressed size, and the percentage saved.
100% private
Compression runs entirely in your browser. Your PDF is never uploaded or stored.
Compress for email
Get your file under common 25 MB attachment limits in seconds, then send straight from the tool.
Print-ready output
High quality and Recommended levels stay sharp for on-screen reading and most print jobs.
Save, Share or Email
Once compressed, download, share via the system share menu, or open your email app pre-filled.
How to compress a PDF in 3 steps
- 1
Open your PDF
Drop a PDF on the page or pick one from your computer. We immediately show its size.
- 2
Pick a level
High quality preserves selectable text; Recommended renders pages as images. Compare file size and legibility.
- 3
Compress & download
Click Compress PDF, see the new size and savings, then Download — or Share / Email.
Compress PDF — frequently asked questions
▶How much can I shrink a PDF?
Results depend on the file. There is no guaranteed reduction. Image-heavy PDFs may benefit from Recommended; an already compact text PDF may stay the same size or grow. Compare the output and keep your original.
▶What's the difference between the two compression settings?
High quality re-saves the PDF with structural optimisations and retains selectable text. Recommended renders pages at 150 DPI as JPEG images. It may reduce image-heavy files, but loses searchable text and interactive document features.
▶Will the compressed PDF still be searchable?
High quality preserves the existing text layer. Recommended rebuilds pages as images, so their text is no longer selectable or searchable.
▶Is the file uploaded to your server?
No. All compression runs inside your web browser using JavaScript. Your file never leaves your computer, which keeps your documents private.
▶Why is my compressed file the same size or larger?
Already optimised PDFs may not shrink further. Rasterising compact text pages can create a larger file. Compare both settings and keep the original if neither result is suitable.
▶Can I compress a PDF for email?
You can try either setting and compare the downloaded file against your email service’s attachment limit. A target size is not guaranteed. Attach the saved file yourself when sending.
▶Does compressing change the page count?
No. The compressed PDF has the same number of pages and the same dimensions as the original. Only the visual quality and storage size change.
▶Will the compressed PDF print well?
Inspect the output at the intended print size. High quality preserves the original page content; Recommended can soften fine details because pages become images. Keep the original for archival use.
▶Are there file-size or page-count limits?
There's no fixed limit, but very large PDFs (hundreds of pages or 100 MB+) take longer because everything happens in your browser. Most files compress in seconds.
Practical guide
Choose compression without losing information you need
Compression results depend on how the source PDF was built. A scanned document may benefit from image compression, while an already compact text document can become larger if every page is turned into an image.
Step by step
- Open the PDF and note the original file size.
- Try High quality first to preserve selectable text. Recommended renders pages as JPEG images at 150 DPI.
- Compare the result’s size and legibility. Download only if it suits your needs; keep the original.
Before you start
There are two settings. High quality re-saves the structure; Recommended makes image-based pages and can remove searchable text, links and interactive fields. Reduction is not guaranteed, and rasterising digitally signed PDFs can discard signature information.
Example workflow
If a scanned handout is too large for an attachment, try Recommended and inspect small print. For a text report where copying words matters, use High quality and accept that savings may be small.
If the result is not what you expected
If the output is larger, use the original or another setting. Do not repeatedly compress an image-based result, because repeated JPEG encoding can reduce clarity.
Keep your original file and check the downloaded result before sharing. Large files may exceed your browser’s memory. Need help? Contact us with the tool name and your browser version; please do not send private documents.
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