A PDF that’s too big to email or upload is a daily frustration — scanned documents and image-heavy decks are the usual culprits. Compression shrinks the file so it actually fits. This guide explains how PDF compression works, the one trade-off to know about, and how to compress a whole batch at once without uploading anything.
TL;DR — Open the free compress PDF tool, drop in your files, pick a level, and download the smaller versions. It runs in your browser — nothing is uploaded.
How PDF compression works here
Each page is re-rendered as a high-quality image and rebuilt into a leaner PDF. That’s what makes scanned and photo-heavy documents drop dramatically in size. The trade-off is simple and worth knowing:
The catch: text in the compressed file becomes part of the page image, so it’s no longer selectable or searchable. Keep your original if you need editable text — use the compressed copy where a small size matters most.
This approach reliably shrinks the files that are usually the problem (scans, screenshots, image-rich reports), where structural-only compression barely helps.
Choosing a level
| Level | What it does | Best for |
|---|---|---|
| Less | Light compression, best quality | Documents you’ll print |
| Recommended | Balanced size and clarity | Most email and upload needs |
| More | Smallest file | Quick sharing where size rules |
Try Recommended first — you’ll see the size saving on each file straight away — and step up to More only if you need to squeeze under a strict limit.
Step by step: compress a PDF
- Open the compress PDF tool.
- Drop in one or more PDFs — scans and image-heavy files shrink the most.
- Pick a compression level and watch the size saving appear per file.
- Download one file, or the whole batch as a zip.
Everything runs on your device, so confidential documents never leave your computer.
Tips for smaller PDFs
- Compress before you merge. Shrink heavy sources first, then merge — the combined file stays light.
- Right-size scans. A document scan doesn’t need to be enormous; the More level brings huge scans down fast.
Where to go next
- Merge PDF files — combine your compressed files into one.
- Convert a PDF to images — export pages as JPG or PNG instead.
- Split a PDF — drop the heavy pages you don’t need.