Adjust PDF Colours
Fine-tune the look of a whole PDF: brighten dark scans, boost contrast on faded copies, or tone down loud colours. Sliders update a live preview, and text stays sharp.
Adjust PDF Colours
Open · Adjust · Save
How to adjust the colours of a PDF
Open your PDF
Drop the file onto the tool.
Move the sliders
Change brightness, contrast and saturation while watching the preview.
Download
Press Save PDF and download.
Why use it
What this free tool does
Brightness
Lighten or darken everything.
Contrast
Make faded documents crisp, or soften harsh ones.
Saturation
Mute or intensify colours.
Pictures included
Photos and scans are adjusted too.
Sharp text
Text stays selectable.
Reset
Back to the original in one click.
Fixing faded and dark documents
Old photocopies and phone scans are often grey and low contrast. Raising contrast and brightness slightly makes them much easier to read and print.
Text, drawings and pictures are all adjusted. Smooth gradients may keep their original colours.
Tip: For scans, try contrast +30 and brightness +10 as a starting point.
Your files stay on your device
Most online PDF sites upload your documents to their servers. Aleynray Ai does the work inside your browser instead, on your own computer or phone.
Nothing is sent anywhere, so contracts, bank statements, IDs and medical forms stay private, and there is no waiting for uploads.
- Free, with no sign-up or limits
- No watermark
- Files never leave your device
- Opens password-protected PDFs
- Works on desktop and mobile
Frequently asked questions
Does it work on scanned PDFs?
Yes. Scans are pictures, and pictures are adjusted.
Will text become blurry?
No. Text stays text.
Can I make a PDF black and white?
Use Greyscale PDF for that.
Is it free?
Yes. There is no sign-up, no limit on files and no watermark.
Are my files uploaded?
No. The tool runs inside your web browser and works on the file on your own device. Nothing is sent to a server, so private documents stay private.