Download
After you buy
One-time payment, one download. Grab the installer below and you're set — it runs offline from there.
After paying, head to the download page and grab Grind — it runs offline from there.
Not sure which Mac you have? Apple menu → About This Mac. If it says "Apple M1/M2/M3/M4", pick Apple Silicon; if it says "Intel", pick Intel.
Grind is notarized with Apple soon; until then macOS shows this warning for independent developers.
Video tutorial
Under two minutes, showing the exact steps above on a real Mac.