You’re in. Thanks!

Download Gradelock below. It works on videos and photos — drag them in and your grade looks right everywhere.

macOS · Apple Silicon & Intel · ~3 MB

Opening it the first time

Gradelock is a brand-new independent app, so macOS double-checks it on the very first open. This is a one-time, 20-second step — after that it opens normally forever.

Open the downloaded Gradelock.dmg and drag Gradelock into your Applications folder.
Open Applications and double-click Gradelock. macOS will block it the first time — that’s expected. Click Done / Cancel.
Open System Settings → Privacy & Security. Scroll down and you’ll see “Gradelock was blocked.” Click Open Anyway, enter your password, then Open.

Still says “damaged”? On some Macs you’ll need this one quick unlock instead. Open Terminal (press ⌘+Space, type “Terminal”, Return), paste the line below, and press Return — then open Gradelock normally.

xattr -dr com.apple.quarantine /Applications/Gradelock.app