Z80 assembly, modernised.
A cross-platform Z80 assembler — the complete Z80 and Z80N instruction sets, macros, structs and enums, an embedded Rhai engine and built-in unit tests, with output for bare-metal Z80 and the whole ZX Spectrum family.
Complete Z80 + Z80N
The full Z80 and Z80N instruction sets, including every ZX Spectrum Next extended opcode.
A real language
Macros, structs, enums and expressions — assembly with the ergonomics of a modern language.
Scriptable & tested
An embedded Rhai engine for compile-time logic, plus built-in unit tests to keep your code honest.
Targets everything
Output bin, hex, sna and .nex for bare-metal Z80 and the whole Spectrum family — on macOS, Windows and Linux.
Latest news
More FantASM news →For a short window today the downloads were broken: a bug in my new release pipeline shipped tiny placeholder files instead of the real builds, so anything you …
FantASM 1.7.5 is available to download.
FantASM 1.7.4 is available to download.