Compress PDF
Runs entirely in your browser
Reduce the file size of a PDF directly in your browser. Choose a compression level and see the exact size reduction — your file is processed entirely on your device and is never uploaded to our servers.
Drag & drop a PDF here
or
Up to 50MB.
File
Keeps text and graphics fully intact and only removes redundant file structure. Best when you need selectable, crisp text.
What is Compress PDF?
Compress PDF reduces the file size of a PDF so it's easier to email, upload or store. Low compression only strips redundant internal file structure, keeping your text and graphics exactly as they were. Medium and High compression redraw each page as an optimized image, which can shrink scanned documents and image-heavy PDFs dramatically at the cost of selectable text.
How to use Compress PDF
- Choose a PDF file, or drag and drop it into the tool.
- Pick a compression level based on whether you need to keep selectable text.
- Click Compress PDF, review the size reduction, then download the result.
Features
- Three compression levels to balance quality and file size.
- Shows the exact original size, compressed size and percentage reduction.
- Low compression preserves selectable text and vector graphics.
- 100% client-side — your PDF never leaves your browser.
When to use this
Say a scanned 40MB signed contract needs to fit under a 25MB email attachment limit. Load the file, choose Medium or High compression (Low won't help much here since the size is coming from scanned images, not file structure), and click Compress PDF. The result screen shows the original size, the new size and the percentage reduction before you download, so you can see whether it's small enough or whether High compression is needed instead.
Tips for compressing a PDF
- Low compression never rasterizes anything — it just resaves the file through pdf-lib, which mainly helps PDFs with redundant internal structure and won't shrink a file whose size comes from large embedded images.
- Medium and High actually re-render every page to a canvas and re-encode it as a JPEG (Medium: 1.5x scale at 75% quality; High: 1x scale at 50% quality) — this is why text stops being selectable at those levels.
- If the compressed version would end up larger than your original file, the tool detects this and serves your original file unchanged instead of a "compressed" file that's actually bigger.
- Medium and High compression only process the first 150 pages in a single run — a longer document will show a note that only part of it was rasterized.
Is Compress PDF safe?
Yes. Medium and High compression re-render pages to a canvas at 1.5x/75% and 1x/50% quality respectively, and Low simply resaves the file with pdf-lib — all of it happening on your device, so the original PDF is never sent to a server.
Frequently Asked Questions
How much smaller will my PDF get?
It depends on the file. Scanned or image-heavy PDFs usually shrink the most. You'll see the exact original size, compressed size and percentage reduction after processing — we never promise a fixed ratio in advance.
Does compression affect text quality?
Low compression keeps your original text and graphics fully intact and just removes redundant file structure. Medium and High compression redraw each page as a compressed image to save more space, which means text is no longer selectable and may look less sharp.
Which compression level should I choose?
Use Low if you need to keep selectable, crisp text. Use Medium or High if the PDF is mostly scanned pages or images and you want the smallest possible file.
Is there a file size limit?
You can compress PDFs up to 50MB. Larger or longer documents may take longer to process depending on your device.