How to use Compress PDF
- Select or drop the PDF you want to compress.
- Choose a level: Light (lossless), Recommended (good quality) or Strong (smallest file).
- Click “Compress PDF” and compare the before/after sizes, then download.
How bopdf compresses — honestly
Light rewrites the PDF structure using compact object streams. It is completely lossless — text stays selectable — but savings depend on how the file was made and are often small. Recommended and Strong render each page to a JPEG image at 144 or 96 DPI and rebuild the PDF from those images. This shrinks scanned documents and photo-heavy PDFs dramatically, but the text is no longer selectable or searchable.
We always show the real before and after size. If compression would not make your file smaller, bopdf tells you and gives you back your original file — we will never hand you a bigger “compressed” file.
When compression works best
- Scanned documents and PDFs exported from phone cameras — often 70–90% smaller with Recommended.
- Presentations full of high-resolution photos.
- Text-only PDFs from Word are usually already small; Light is the best choice for them.
Server-based tools can sometimes squeeze a little more out of text PDFs by re-encoding fonts and images individually. bopdf trades that for the guarantee that your file never leaves your device.
Need a specific size, like 1 MB or 200 KB?
Upload forms often have a strict limit. Use Compress PDF to a specific size: pick 100 KB, 200 KB, 500 KB, 1 MB, 2 MB, 5 MB or any custom size and bopdf finds the best quality that fits.
🔒 Your files never leave your device
bopdf processes your documents locally with JavaScript (pdf-lib and Mozilla pdf.js) inside your browser tab. Your PDF is never uploaded, stored or seen by us — you can even disconnect from the internet after the page loads and the tool keeps working. When you close the tab, everything is gone.
Frequently asked questions
How do I compress a PDF to 1 MB or 200 KB?
Use our Compress PDF to a specific size tool: choose the target and bopdf automatically picks the highest quality that stays under it.
How can I compress a PDF without losing quality?
Choose Light. It is lossless — text, images and links are untouched — but the size reduction is usually modest. Stronger levels trade quality for size.
Why is my text no longer selectable?
Recommended and Strong convert pages to images to save space. Use Light if you need selectable text, links or form fields.
Why didn’t my file get smaller?
Some PDFs are already optimized. Rather than giving you a larger file, bopdf returns the original and tells you so. Try a stronger level if quality loss is acceptable.
What size is OK for email?
Most email services accept attachments up to 20–25 MB. Recommended compression usually brings scans well under that.
Is compression done on a server?
No. Pages are rendered and re-encoded by your own browser; the file is never uploaded.
Are my files uploaded to a server?
No. Everything happens in your browser on your own device. Files are never sent over the internet, which makes bopdf suitable for confidential documents.
Is there a file size limit?
There is no fixed limit, but very large files (hundreds of MB) depend on your device memory. On phones, files up to about 100 MB usually work well.