Free tool · 100% private
Compress PDF
Shrink a large, scanned or image-heavy PDF down to size. Everything runs inside your browser: your file is never uploaded, so nothing can leak. It even works offline.
Choose a PDF file or drop it here
One PDF · it stays on your device
How hard should we compress?
Best for scanned documents, photos & image-heavy PDFs. To shrink the file, pages are re-saved as images, so text becomes non-selectable. If you need searchable text, keep your original.
Compressing your PDF…
Re-encoding each page entirely on your device
🔒 Nothing is uploaded — this all happens on your device
- ✓Reading your PDF on this device
- ✓Re-encoding pages as images
- ✓Rebuilding & verifying (no corruption)
- ✓Checking it actually got smaller
Compressed & verified
Couldn’t compress this PDF
Juggling lecture PDFs, timetables and deadlines?
AttendFlow keeps your attendance, timetable, exams and notes together — free.
Get AttendFlow — free
How to compress a PDF (without uploading it)
Most "compress PDF" websites upload your file to their servers, shrink it there, and send it back — then promise to delete it an hour later. This one is different: it does the whole job on your device, and it checks its own work before handing you the smaller file.
- 1Add your PDF. Drag it onto the box or click to pick. It loads straight into your browser's memory — nothing is sent anywhere.
- 2Choose a level. Strong for the smallest file, Recommended for a balance, or Light for the best quality. Each page is re-saved as an image at a lower resolution — that's what shrinks it.
- 3Compress, verify & download. Your browser rebuilds the PDF, re-opens it to confirm every page is there, and only offers a download if the file genuinely got smaller.
Why this is honest. Because the tool compares the result to your original, it never hands you a bigger file dressed up as "compressed". If it can't beat your original, it says so and gives your file back untouched — and since nothing is ever uploaded, there's no copy on any server to leak.
Frequently asked questions
Is my PDF uploaded to a server?
No. This tool runs 100% in your browser using JavaScript. Your file is read into your device's memory and compressed locally — it's never sent to any server, so there's no way for it to leak. It even works offline once the page has loaded.
How does the compression work?
Each page is rendered to an image and re-saved as a JPEG at a lower resolution, then a new PDF is rebuilt from those images. This is what shrinks the file. Because pages become images, the text is no longer selectable — so it works best for scanned documents, photos and image-heavy PDFs.
Will the text still be selectable afterwards?
No. To shrink the file, each page is re-saved as an image, so text becomes non-selectable. If you need searchable, selectable text, keep the original — this tool is designed for image-heavy and scanned PDFs where size matters most.
What if my PDF is already small?
The tool compares the new file to your original. If it can't make it meaningfully smaller without hurting quality, it tells you honestly and offers your original file back unchanged — it will never hand you a bigger file and call it compressed.
Is it really free?
Yes — completely free, no sign-up, no watermark, no account limits. It's part of AttendFlow's free student tools.
One app for the rest of student life
AttendFlow tracks your attendance and bunk budget, timetable, exams, marks and notes — and warns you before you slip below 75%.
Get AttendFlow on Google Play Free plan available · Pro from ₹99/mo · cancel anytime