This app is a precision overlay tool for macOS — built to make alignment of window sizing & content “pixel-perfect”, making comparisons easier while you’re in other apps.
Launch this app. If you’re unlicensed, you’ll be prompted to register and activate a key. Once licensed, the overlay features become available.
Tip: Keep your license key somewhere safe (email + notes). You can re-enter it later from the License menu.
Registration is email-based. You’ll receive a license key, then paste it into the in-app License window and click Activate.
Go to Registration →
Set the grid to be any number of horizontal & vertical lines and you'll get evenly spaced grid lines spanning the full screen.
Guides can be placed at any position on screen using hotkeys of your choosing. Moving and deleting an individual guide is possible with another hotkey of your choosing. Grids & guides can be independently assigned any thickness, any color with transparency, and even shadowing should you choose.
Window snapping is available for any standard window of any app. Pressing the snap hotkey invokes the magnetic property. You can set the distance of the magnetic feel to your preference.
Indicators will appear on the candidate sides of the window when within snapping distance of a grid or guide line. The candidate lines will also flash as further indication of what will snap when the mouse-up event occurs.
(For more on hotkey assignments see Prefs Window below)
Important: Make sure you only have one occurrence of Grids&Guides on your machine!
License window won’t accept key: verify the key is complete (all groups) and pasted cleanly.
Overlay not visible: confirm the app is running, and verify any required macOS permissions.
Snapping not working: confirm the app is running, and verify any required macOS permissions.
Something feels “stuck”: quit and relaunch, then re-check permissions.
If you're still having trouble, remove all permissions from System Settings and re-apply them.
This help page will expand as this app evolves: shortcuts, overlay modes, preferences, and workflow tips.