How to compress a PDF online
- 1
Select your PDF
Click Choose PDF file or drag the file onto the page. You can add up to 3 files at once on Free.
- 2
Choose how small it should be
Keep Recommended for most files, or enter a maximum size such as 2 MB.
- 3
Check the preview
Compare the original and compressed pages side by side before you save anything.
- 4
Download your file
Save it, continue with another tool, or press Delete now to remove it from our server.
Choose the right compression level
Compression only changes images and hidden data. Text and line drawings stay exactly as they are. Try the levels below on an example 12.4 MB brochure.
- Image resolution
- 150 dpi
- Image quality
- Medium
- Best for
- Email, sharing
Compress a PDF to a specific size
Job portals, visa applications and university systems often reject files over a set size. Choose a target and we’ll reduce the file until it fits, then show you the result before you download it.
Why is my PDF so large?
Most large PDFs are large for one of three reasons. Knowing which one helps you pick the right setting.
High-resolution photos
Images saved at print quality. Recommended usually cuts these by 70% or more.
Scanned pages
Each page is a picture. Maximum with grayscale works best.
Embedded fonts and data
Unused fonts and edit history. Even Light removes these.
About compressing PDFs
Most large PDFs are large because of their images: photos saved at print quality, or scanned pages where every page is a picture. Compression resamples those images to a lower resolution and removes unused objects, such as leftover fonts and edit history. Text and line drawings stay exactly as they are, so they remain sharp and selectable. Light reduces images to 300 dpi, which keeps print quality and suits archiving. Recommended reduces them to 150 dpi, which looks crisp on any screen and is the right choice for email and sharing. Maximum reduces them to 72 dpi for the smallest file, which suits strict upload limits but can make photos look soft when zoomed in. Grayscale removes colour from images and helps most with scanned documents. A file with few images, such as a text-only report, will not shrink much. Compression never gives you a bigger file: if the result would be larger, you get your original back with a note that it is already well compressed. If a portal sets a maximum size, use Compress to a size instead.
Limits: files up to 25 MB with a free account, 200 MB on Pro and 500 MB on Business; up to 3 files per task on Free, 50 on Pro and 200 on Business. A free account includes 10 server tasks a day.
Before you sign in, files can be up to 25 MB and you can run 10 server tasks a day. A free account raises this to 25 MB and 10 tasks a day.
Is it safe to compress a PDF online?
Compression needs our servers, so here is exactly what happens to your file and when.
- 0:00
Uploaded
Over an encrypted connection to a UK server.
- 0:04
Compressed
Automatically. No person opens it.
- 0:05
Downloaded
Or removed at once with Delete now.
- 1:00:00
Deleted
Both files removed automatically.
Privacy: your file is uploaded over an encrypted connection to our UK servers, processed automatically with no person opening it, and deleted within 2 hours (1 hour on Free), or straight away with Delete now.
How to use the PDF tools: Step-by-step help with every tool, limits and your files.
Compress PDF: frequently asked questions
Will compression reduce the quality of my text?
No. Only images and hidden data are changed. Text and vector graphics stay exactly as they are.
Which compression level should I choose?
Recommended (150 dpi) for email and sharing, Light (300 dpi) for printing, and Maximum (72 dpi) when you need the smallest possible file.
Why did my file not get smaller?
It may have few images or already be well compressed. We never return a bigger file, so you get the original back with a note.
How do I compress a PDF to under 2 MB?
Use Compress to a size, enter 2 MB as the target, and it tries progressively stronger settings until the file fits.