Drop your PDF here
Adjust PDF Brightness, Contrast & Colors
Fix dark scans, rescue faded text and re-balance color in any PDF. Drag the brightness, contrast, saturation and RGB sliders, watch the live preview, then download — free, with no watermark and no upload.
or drop a PDF anywhere on this page
Quick presets
Light
Color
Tip: double-click any slider to reset it to zero.
Effects
Output
Color changes are applied to the rendered page, so the exported PDF contains images rather than selectable text. Pick a higher DPI for sharper results and a larger file.
Full color control over every PDF page
Everything you would expect from a photo editor, applied to a PDF document — with a live preview so you can see exactly what you are getting before you export.
Brightness & contrast
Lighten a PDF that scanned too dark, or push the contrast up until faded, low-ink text is crisp and readable again.
Saturation & exposure
Make charts and photos pop with more saturation, or pull washed-out color back under control. Exposure rescues badly lit phone scans.
Individual RGB levels
Separate red, green and blue sliders let you neutralize a color cast — the yellow tinge on old paper or the blue cast from an office scanner.
Temperature & tint
Warm a document up or cool it down, and correct green or magenta casts with the tint slider — the same white-balance controls photographers use.
Invert for dark mode
Flip a PDF to white-on-black in one click for comfortable night reading, or to save ink when a page is mostly dark.
Private by design
Your PDF is opened, adjusted and rebuilt entirely inside your browser. Nothing is uploaded, stored, queued or seen by anyone else.
How to adjust PDF colors in four steps
No account, no software install, no waiting in an upload queue.
Open your PDF
Click Select PDF File or drag a document onto the page. It opens straight away in your browser.
Move the sliders
Adjust brightness, contrast, saturation, exposure, temperature, tint and the red, green and blue channels — or start from a preset.
Check every page
Page through the document and hold Compare to flip between the original and your edit.
Apply & download
Choose an output quality and click apply. Your corrected PDF downloads immediately, watermark-free.
Free online PDF brightness and contrast editor
Everything you need to know about correcting the color of a PDF in your browser.
Why scanned PDFs need color correction
Scanned documents rarely come out right the first time. A phone photo of a contract is too dark in one corner, an old receipt has yellowed, a library scan of a textbook page is grey instead of white. Most PDF readers will happily show you the problem but give you no way to fix it, and desktop editors like Adobe Acrobat put color correction behind a subscription.
This tool gives you the missing controls. Load any PDF and you get the same adjustments a photo editor offers — brightness, contrast, saturation, exposure, color temperature, tint and independent red, green and blue levels — applied uniformly across every page of the document.
What you can fix with it
- Dark or underexposed scans. Raise brightness and exposure until the page reads as white paper again.
- Faded or low-ink text. Push contrast up and brightness slightly down to make grey text properly black.
- Yellowed or aged paper. Drop the red channel or cool the temperature to neutralize the cast.
- Color casts from a scanner. Use the individual RGB sliders to remove a blue or green tint that the scanner baked in.
- Documents you need to print cheaply. Switch on grayscale and raise contrast to save color ink without losing legibility.
- Late-night reading. Invert the colors for a dark-mode PDF that is far easier on the eyes.
Does it change the text in my PDF?
Color adjustment works on pixels, so each page is rendered and re-encoded as an image inside the new PDF. The layout, page size and page order are preserved exactly, but text in the exported file is no longer selectable or searchable. If you need the text layer intact, adjust your source document instead, or run OCR on the result to make it searchable again.
Is my document private?
Yes. Everything happens locally in your browser using your own device's processing power. The PDF is never transmitted to PixelMagicTools or anywhere else, there is no server-side copy, and nothing is retained after you close the tab. That makes it safe for contracts, medical records, payslips and anything else you would not want to hand to a third party.
Works on any device
The tool runs in Chrome, Firefox, Safari and Edge on Windows, macOS, Linux, Android and iOS. There is nothing to install and no account to create. Very large documents at 300 DPI are limited only by the memory available on your device — if a big file struggles, drop the output quality to 150 DPI.
Related PDF tools
Keep going with the rest of the free PixelMagicTools PDF toolkit.