Use the invert image tool as you read.
How to Invert an Image
Three routes, one result: complementary colors. Start with the browser tool below if you want the inverted file in under a minute.
Drop a photo here
Or paste with Ctrl+V / Cmd+V. JPG, PNG, GIF, and WebP stay on this device.
Paste from clipboard is ready
Your image never leaves your browser. Invert runs on this page with the Canvas API.
1
Invert an image in your browser
Open the invert image tool, upload or paste a photo, and download the preview. This is the fastest path if you do not want another app.
2
Invert an image on a phone
Most phone editors bury invert under filters or curves. You can instead open this page in mobile Safari or Chrome, choose a photo, and save the inverted file to your camera roll.
3
Invert an image in a desktop editor
In Photoshop, Image > Adjustments > Invert. In GIMP, Colors > Invert. Those menus do the same RGB flip this page runs locally in a canvas.
What you should see after invert
Highlights become shadows. Warm hues swing to cool hues. A white background becomes black. If the file has transparency, the transparent pixels stay transparent. That is how you know the invert image pass kept the alpha channel.