Stop your keyboard
from double typing.
ChatterFix is a lightweight app that blocks unwanted double keypresses an old or worn-out keyboard might trigger.
Free, with the source on GitHub. macOS 10.15+ (Intel and Apple Silicon) and Windows 10 / 11.
Simple fix, no typing delay.
Keyboard chatter happens within a few milliseconds after a keypress. ChatterFix adds a small buffer after each one to make sure a second input doesn't trigger.
Install ChatterFix
- Open the .dmg and drag ChatterFix into Applications.
- The first time only, right-click ChatterFix in Applications and choose Open. The same warning appears again, but this time it has an Open button. Click it. Double-clicking, or launching from Launchpad, will not work yet.
- Allow Accessibility when asked. Filtering starts on its own.
- That's it. It starts with your Mac from now on, which you can turn off from the menu bar at any time.
Double-clicked first and got "Apple cannot check it for malicious software" and "this software needs to be updated"? Nothing is wrong with the app and there is nothing to update. macOS shows that message for any app not signed with a paid Apple certificate. Its only buttons are Show in Finder and OK, and neither one opens the app. Click OK, then use the right-click and Open step above. After that it opens normally forever, from the Dock or Launchpad too.
- Run ChatterFix.exe. No installer.
- If a blue "Windows protected your PC" box appears, click More info, then Run anyway.
- It lands in the system tray and starts working right away.
- That's it. It starts with Windows from now on, which you can turn off from the tray menu at any time.
That box is SmartScreen, and it appears for any app not signed with a paid certificate. The Run anyway button is hidden behind More info, which is easy to miss.
Those prompts are normal for free apps without a paid certificate. Everything ChatterFix does is open on GitHub, so you can read the code before running it.
Questions
Does it record what I type?
No. It only looks at key timing, never what you type. Nothing is stored, and the code is public.
Will it add lag or affect gaming?
No added lag, real presses register instantly. The one catch is a key you hold down that chatters. Hold W to move while the W switch chatters, and ChatterFix may block the stray repeat, which the game can read as you letting go, so you briefly stop. If a movement key chatters, lower the sensitivity for that key or pause ChatterFix while you play. Games with kernel-level anti-cheat sit below ChatterFix, so it has no effect there anyway.
Which keys does it fix?
Any normal key. The Blocked Keys list shows which of yours are acting up, and each one can be given its own sensitivity. Modifiers like Shift and Ctrl are not filtered, but they rarely chatter.
Can I set a different sensitivity for one bad key?
Yes. Chatter is usually one worn switch rather than the whole keyboard, so open Blocked Keys, pick the key, and give it its own setting. Everything else keeps the global one. You can also type an exact millisecond value instead of using a preset, or choose Only Keys I Choose so that nothing is filtered except the keys you name.
It caught a real double letter. What do I do?
Lower the sensitivity one step. If chatter starts slipping through, raise it back. Standard fits most keyboards, and you can set it per key if only one is a problem.
Is it really free?
Yes, free for everyone, at home or at work. No ads, no account. The source is on GitHub under the MIT license with the Commons Clause, so you can read it and fork it, but not sell it.
My Mac says it "can't check it for malicious software". Is something wrong?
No. That is Gatekeeper's standard message for any app not signed with a paid Apple certificate, which costs $99 a year. It appears before the app has run at all, so it is not a judgement about ChatterFix, and the line about needing an update is misleading, because there is nothing newer to get. Right-click ChatterFix in Applications and choose Open. The same warning appears, but this time with an Open button that runs it, and it launches normally from then on. If you would rather not take our word for it, the whole app is a few hundred lines on GitHub, and you can build it yourself.
How do I remove it?
macOS: quit it and drag ChatterFix to the Trash. Windows: quit it and delete the .exe. Nothing is left behind.