win11-toggle-rounded-corners

Win11 Toggle Rounded Corners

A simple utility to disable rounded window corners on Windows 11

Download

An installer as well as the standalone binary for portable use can be downloaded here.

Windows 11 on x64 only. Some Anti-Virus/EDR products may block access to dwm.exe.

Usage

The program requires administrator privileges and asks for them itself, so you get the usual UAC prompt when you start it. There is no need to open an elevated terminal first.

win11-toggle-rounded-corners --disable   # square corners
win11-toggle-rounded-corners --small     # small rounding

Run it with no arguments to toggle.

The patch is applied to dwm.exe in memory and is lost whenever dwm.exe restarts (logoff, reboot, or a crash).

The installer re-applies it with a logon task, so it persists; the portable binary is one shot.

Reverting

How to undo the patch depends on how you installed it:

• Portable: Run the binary again with --enable, or just reboot.
• Installer: Uninstall it from Settings → Apps. This removes the scheduled task that re-applies the patch at every logon. Your current session will still show square corners until you reboot; after the reboot nothing re-applies the patch and rounded corners return on their own.

If a leftover task is still squaring corners after uninstalling, you can remove it manually from an elevated Command Prompt:

schtasks /Delete /F /TN "Run win11-toggle-rounded-corners as admin on logon"

Build

You need clang-cl or MSVC with C++23/26 support, plus meson and ninja.

First clone the repo

git clone 'https://github.com/rich-ayr/win11-toggle-rounded-corners.git'

Then simply build it with meson

meson setup build
meson compile -C build