nasm.exe: which program is it?
nasm.exe is a program file that 5 Windows programs install, the best known being WinLibs (POSIX threads, MSVCRT runtime). The list below names each one with its publisher and install folder.
| App | Publisher | Latest version | Default install folder |
|---|---|---|---|
 WinLibs (POSIX threads, MSVCRT runtime) | Brecht Sanders | 16.2.0-14.0.0-r3 | — |
 WinLibs (POSIX threads, UCRT runtime) | Brecht Sanders | 16.2.0-14.0.0-r3 | — |
 WinLibs (MCF threads, UCRT runtime) | Brecht Sanders | 16.1.0-14.0.0-r1 | — |
 WinLibs (POSIX threads, MSVCRT runtime, LLVM included) | Brecht Sanders | 14.2.0-19.1.7-12.0.0-r3 | — |
 WinLibs (POSIX threads, UCRT runtime, LLVM included) | Brecht Sanders | 14.2.0-19.1.1-12.0.0-r2 | — |
Frequently asked questions
Is nasm.exe safe?
nasm.exe is a normal part of WinLibs (POSIX threads, MSVCRT runtime) when it sits in the program's install folder and carries the publisher's digital signature. A file with the same name in another folder can be something else: check its signature and hash.
Where is nasm.exe located?
In the program's install folder, which the installer chooses; winget puts portable programs under %LOCALAPPDATA%\Microsoft\WinGet\Packages.
How do I remove nasm.exe?
Uninstall WinLibs (POSIX threads, MSVCRT runtime) through Settings → Apps or with winget; the uninstaller removes nasm.exe with it. Deleting the file alone leaves the rest of the program behind.