This is the project webpage for the Netwide Assembler (NASM), an asssembler for the x86 CPU architecture portable to nearly every modern platform, and with code generation for many platforms old and new.


As of version 2.07, NASM is now under the Simplified (2-clause) BSD license. The details of the license are available in the documentation.

Latest version

Stable 2.16.03 History
Builds List
Snapshots Latest, List

For users of RPM-based Linux distributions (e.g. Fedora, Red Hat, SUSE, ...), you can download the official NASM builds using dnf or yum by installing nasm.repo in your /etc/yum/yum.repos.d directory.

Infrastructure Change

On July 1, 2020, the official NASM git repository moved to github.

The previous repository on repo.or.cz is no longer maintained.

Development Team

NASM was originally developed by Simon Tatham and Julian Hall, and is now maintained by a team led by H. Peter Anvin.

Currently active team members are:

  • H. Peter Anvin
  • Cyrill Gorcunov
  • Chang Seok Bae
  • Jim Kukunas
  • Frank B. Kotler

... with support from many others, and we are always looking for more developers.

Your reports aren't going to /dev/null

We're looking for your comments, suggestions and, of course, bug-reports. Report any suspicious behavior you encounter to help us improve the NASM for everyone!

Please post your messages to the mailing list, or file a bug report.

Don't worry if your report is not immediately addressed, even within the first few days, as this is usual for us. Your report will, however, be recorded and dealt with, of course, as time permits.