Online Tool Store
Change PNG Brightness
Upload a PNG and adjust its brightness with a live-updating slider, transparency preserved. Runs entirely in your browser.
🔒 This tool runs entirely in your browser. Your files are never uploaded to a server.
+30
Result
Example shown — upload your own PNG to adjust its brightness.
How it works
- Upload a PNG.
- Drag the brightness slider.
- Download the brightness-adjusted result.
Adjustment reads the image's pixel data via the canvas API and adds the chosen offset to each pixel's red, green, and blue values (clamped to 0-255), leaving alpha untouched — the same math behind a brightness slider in any photo editor.
FAQ
Is my image uploaded anywhere?
No. Brightness is adjusted entirely in your browser using the canvas API — your PNG is never sent to a server.
Does it preserve transparency?
Yes — only the RGB channels are adjusted. The alpha channel is left untouched.
What range can I adjust brightness by?
From -100 (much darker) to +100 (much brighter), with a live preview as you drag the slider.
Does this reduce image quality?
No — pixel values are adjusted directly; resolution and compression stay the same.
How we compare
| Feature | Online Tool Store | Photoshop / GIMP | Phone gallery editor |
|---|---|---|---|
| No file upload — runs in your browser | ✓ | Desktop install required | ✓ |
| Free, no sign-up | ✓ | Photoshop is paid | ✓ |
Full image editors are the right call for complex edits. PNG Brightness Changer is for the one-off case — a quick brightness fix — done in one upload with no install.