Comparison of assemblers

This is a list of assemblers: computer programs that translate assembly language source code into binary programs. Some assemblers are components of a compiler system for a high level language and may have limited or no usable functionality outside of the compiler system. Some assemblers are hosted on the target processor and operating system, while other assemblers (cross-assemblers) may run under an unrelated operating system or processor. For example, assemblers for embedded systems are not usually hosted on the target system since it would not have the storage and terminal I/O to permit entry of a program from a keyboard. An assembler may have a single target processor or may have options to support multiple processor types. Very simple assemblers may lack features, such as macros, present in more powerful versions.

As part of a compiler suite

GNU Assembler (gas): GPL: many target instruction sets including ARM architecture, Atmel AVR, x86, x86-64, Freescale 68HC11, Freescale v4e, Motorola 680x0, MIPS, PowerPC, IBM System z, TI MSP430, Zilog Z80.
ASxxxx Cross Assembler (part of the Small Device C Compiler project): GPL: several target instruction sets including Intel 8051, Zilog Z80, Freescale 68HC08, PIC microcontroller.
The Amsterdam Compiler Kit (ACK) targets many architectures of the 1980s, including 6502, 6800, 680x0, ARM, x86, Zilog Z80 and Z8000.
LLVM targets many platforms, however emits no per-target assembly language, instead more high-level typed intermediate representation assembly-like language used.
Some others self-hosted native-targeted language implementations (like Go, Free Pascal, SBCL) have their own assemblers with multiple targets. They may be used for inline assembly inside language, or even included as a library, but not always suitable for standalone application - no command-line tool exists, or only intermediate representation used as a source, or support for targets very limited.

Single target assemblers

6502 assemblers

Assembler	Developer	FOSS	License	Instruction set	Host platform
Atari Assembler Editor	Shepardson Microsystems	No	Proprietary	MOS Technology 6502	Atari 8-bit family
Atari Macro Assembler	Shepardson Microsystems	No	Proprietary	MOS Technology 6502	Atari 8-bit family
Lisa	Randall Hyde	No	Proprietary	MOS Technology 6502	Apple II series
MAC/65	Optimized Systems Software	No	Proprietary	MOS Technology 6502, WDC 65C02	Atari 8-bit family
Merlin	Glen Bredon	Yes	Public-domain	MOS Technology 6502, WDC 65C02	Apple II series
vasm	Volker Barthelmann, Frank Wille		Free	MOS Technology 6502	various
k2asm	Andre Kaesmacher, Hauke Brandes, Börje Sieling	Yes	Artistic License	MOS Technology 6502	Linux, Windows, macOS, possibly other Unices
rmac	James Hammons, George Nakos, Landon Dyer	Yes	Free	MOS Technology 6502	Linux, Windows, macOS
xasm	Piotr Fusik	Yes	Free	MOS Technology 6502	Linux, Windows, macOS

680x0 assemblers

Assembler	Developer	FOSS	License	Instruction set	Host platform	Development active
ASM-One Macro Assembler	Rune Gram-Madsen	No	Free	Motorola 680x0	Commodore Amiga	No
GNU Assembler	GNU Project	Yes	Free	Motorola 680x0	various
vasm	Volker Barthelmann, Frank Wille	No	Proprietary	Motorola 680x0	various	Yes
rmac	James Hammons, George Nakos, Landon Dyer	Yes	Free	MOS Technology 6502	Linux, Windows, macOS	Yes

ARM assemblers

Assembler	Developer	FOSS	License	Instruction set	Host platform
GNU Assembler	GNU Project	Yes	Free	ARM	various
vasm			Free	ARM	various

IBM mainframe assemblers

Assembler	Developer	License	Instruction set	Host platform
IBM 1410/7010 OS Autocoder	IBM	Free	IBM 1410 IBM 7010	IBM 1410/7010 Operating System
7070/7074 Autocoder	IBM	Free	IBM 7070/7072/7074
7080 Autocoder III	IBM	Free	IBM 7080	IBM 7058 Processor
Symbolic Coding and Assembly Technique (SCAT)	Share	Free	IBM 709 7090/7094/7094 II	SHARE Operating System (SOS)
FORTRAN II Assembly Program (FAP)	IBM	Free	IBM 709 7090/7094/7094 II	IBM 7090/94 IBSYS
Macro Assembly Program (MAP)	IBM	Free	IBM 709 IBM 7040/7044 7090/7094/7094 II	IBM IBSYS/IBJOB
BAL		Free	IBM System/360	IBM BPS/360
HLASM		Proprietary	z/Architecture	numerous
IBM Assembler D		Free	IBM System/360	IBM DOS/360
IBM Assembler E		Free	IBM System/360	IBM OS/360
IBM Assembler F		Free	IBM System/360	IBM OS/360 and CP-67/CMS
IBM Assembler H		Proprietary	IBM System/360 and System/370	IBM OS/360 and successors
IBM Assembler XF		Free	IBM System/370	numerous
PL360		Free	IBM System/360	IBM OS/360

POWER, PowerPC, and Power ISA assemblers

Assembler	Developer	FOSS	License	Instruction set	Host platform
IBM AIX assembler		No	Proprietary	POWER	IBM AIX
vasm			Free	PowerPC	various

x86 assemblers

Assembler	Developer	Operating system	FOSS	License	Development active
A86/A386	Eric Isaacson	Windows, DOS	No	Proprietary	No
ACK	Andrew Tanenbaum, Ceriel Jacobs	Linux, MINIX, Unix-like	Yes	BSD since 2003	1985-? ^[1]
IBM ALP	IBM	OS/2	No	Proprietary	No
AT&T	AT&T	Unix System V	No	Proprietary	1985-?^[2]
Digital Research ASM86	Digital Research	CP/M-86, DOS, Intel's ISIS and iRMX	No	Proprietary	1978-1992
FASM	Tomasz Grysztar	Windows, DOS, Linux, Unix-like	Yes	BSD with added Copyleft	Yes
GAS	GNU Project	Unix-like, Windows, DOS, OS/2	Yes	GNU GPL	Since 1987
HLA	Randall Hyde	Windows, Linux, FreeBSD, macOS	Yes	Public domain	Yes
Open Watcom Assembler (HJWASM a.k.a. UASM, JWASM, WASM)	Watcom	Linux, Windows, DOS, FreeBSD, OS/2	approved by OSI, but not by FSF	Sybase Open Watcom Public	Yes
MASM	Microsoft	Windows, DOS, OS/2	No	Microsoft EULA	Since 1981^[3]
NASM	Simon Tatham, Julian Hall, Hans Peter Anvin, et al.	Linux, macOS, Windows, DOS, OS/2	Yes	BSD	Yes
Tim Paterson's ASM	Tim Paterson	86-DOS, DOS DEBUG	No	Proprietary	1979-1983
TASM	Borland	Windows, DOS	No	Proprietary	?^[4]^[5]
TCCASM	Fabrice Bellard	Unix-like, Windows	Yes	LGPL	Yes
vasm		various	Yes	Free	Yes
86-Assembler for DOS	Stephen Duffy	DOS	Yes	GPL2	No
Xenix	Microsoft	Xenix 2.3 and 3.0 (before 1985)	No	Proprietary	1982-1984
Yasm^[1]		Windows, DOS, Linux, Unix-like	Yes	BSD	No^[6]

^ Part of the MINIX 3 source tree, but without obvious development activity.
^ Developed by Interactive Systems Corporation in 1986 when they ported UNIX System V to Intel iAPX286 and 80386 architectures. Archetypical of ATT syntax because it was used as reference for GAS. Still used for The SCO Group's products, UnixWare and OpenServer.
^ Home site appears inactive. Also offered as part of FreeBSD Ports, in bcc-1995.03.12.
^ Active, supported, but unadvertised.
^ Developed in 1982 at MIT as a cross-assembler, it was picked up by Interactive Systems Corporation in 1983 when they developed PC/IX under IBM contract. The syntax was later used as base for ACK assembler, to be used in MINIX 1.x toolchain.
^ RosAsm project on WebArchive.org.
^ Part of the C++Builder Tool Chain, but not sold as a stand-alone product, or marketed since the CodeGear spin-off; Borland was still selling it until then. Version 5.0, the last, is dated 1996.
^ Turbo Assembler was developed as Turbo Editasm by Uriah Barnett from Speedware Inc (Sacramento, CA) between 1984 and 1987, then later sold to, or marketed by, Borland as their Turbo Assembler.
^ Last stable version 1.3.0 was released in August 2014, and low maintenance since then: https://github.com/yasm/yasm

x86-64 assemblers


Assembler	Developer	Operating system	FOSS	License	Development active
FASM	Tomasz Grysztar	DOS, Unix-like, Windows	Yes	BSD	Yes
GAS	GNU Project	DOS, OS/2, Unix-like, Windows	Yes	GNU GPL	Yes
MASM	Microsoft	DOS, OS/2, Windows\|Xenix	No	Commercial	Yes
NASM	Simon Tatham, Julian Hall, Hans Peter Anvin, et al.	DOS, Linux, macOS, OS/2, Windows	Yes	BSD	Yes
Open Watcom Assembler	Watcom	DOS, FreeBSD, Linux, OS/2, Windows	approved by OSI, but not by FSF	Sybase Open Watcom Public	Yes
POASM		Windows, Windows Mobile	No	Freeware	Yes
TCCASM	Fabrice Bellard	Unix-like, Windows	Yes	GNU LGPL	Yes
Yasm^[2]		DOS, Unix-like, Windows	Yes	BSD	No

Z80 assemblers


Assembler	Developer	Operating system	FOSS	License	Development active
Microsoft MACRO-80	Microsoft	CP/M, ISIS-II, TRSDOS, TEKDOS, MSX-DOS	No	Commercial	No
Zeus Assembler	Crystal Computing		No	Commercial	No
z80asm		Unix-like, Windows	Yes	GNU GPL	No

Other

Assembler	Developer	FOSS	License	Instruction set	Host platform
Assembly Language for Multics (ALM)		Yes	MIT	GE-645 Honeywell 6180	GE-645 Honeywell 6180
The Macroassembler AS	Alfred Arnold		Free	29xxx, AVR, 65816, ACE, F2MC-8L, F2MC-16L, HMCS400, 6301, 6309, H8/300(H), H8/500, SH7000 / SH7600 / SH7700, HuC6280, PPC403GA, 4004/4040, 8008, MCS-48, MCS-41, MCS-51, MCS-251, MCS-96/196/296, 8080/8085, 8086/80186, i960, CDP1802(A)/1804(A)/1805(A), LatticeMico8, PIC 16C5x, PIC 16C8x, PIC 17C42, MELPS-740, MELPS-7700, MELPS-4500, M16, M16C, 68000 (up to 68040), ColdFire, DSP56000, DSP56300, PowerPC 601/505, M-Core, 6800, 68HC11(K4), 6805, 68HC(S)08, 6809, 68HC12 incl. XGATE, 68HC16, 68RS08, SC/MP, INS807x, COP4, COP8, SC14xxx, µpD7720/7725, µpD77230, µpD78C1x, 75K0, 78K0, 78K2, 78K3, 78K4, V30/35, OLMS-40, OLMS-50, XA, 6502, (W)65(S)C02, 65C19, 80C382, 80C166/167, 2650, 8X30x, ST6, ST7, ST9, 6804, SYM53C8xx, TMS3201x, TMS320C2x, TMS320C20x, TMS320C3x, TMS320C4x, TMS320C5x, TMS320C54x, TMS320C6x, TMS7000, TMS9900, TMS370xxx, MSP430(X), TLCS-900, TLCS-90, TLCS-870, TLCS-47, TLCS-9000, TC9331, KCPSM/KCPSM3 ('PicoBlaze'), Z80, Z180, Z380, Z8, eZ8, MIL STD 1750	Win32, DOS/DPMI, DOS (no longer maintained), OS/2 (no longer maintained), Linux
Babbage		No	Proprietary	GEC 4000 series	GEC 4000 series
COMPASS^[3]	Control Data Corporation	No	Proprietary	CDC mainframe	CDC mainframe
MACRO-10	Digital Equipment Corporation		Free	PDP-10	PDP-10
MACRO-11	Digital Equipment Corporation		Free	PDP-11	PDP-11
vasm			Free	Zilog Z80, Motorola 6800 family	various
GPASM	James Bowman, Craig Franklin, David Barnett	Yes	GNU GPL	PIC microcontroller	many
MIPS			Free	MIPS	MIPS
Symbolic Optimal Assembly Program (SOAP)		No	Proprietary	IBM 650	IBM 650
Technical Assembly System (TASS)			Free	IBM 650	IBM 650
Autocoder^[4]			Free	IBM 705, 14xx, 1410, 7010, 7070, 7072, 7074, 7080	various
Fortran Assembly Program (FAP)			Free	IBM 709, 704x, 709x	Fortran Monitor System, IBSYS
GCOS Macro Assembly Program (GMAP)			Free	GE-600 series, Honeywell 6000 series	GCOS
Macro Assembly Program (MAP)			Free	IBM 709, 704x, 709x	IBSYS/IBJOB on 709, 704x, 709x
Meta-Symbol			Free	SDS Sigma series	BTM, UTS, CP-V
Symbolic Assembly Program (SAP)			Free	IBM 704	IBM 704
Symbolic Programming System (SPS)^[5]	Gary Mokotoff		Free	IBM 14xx, 1620, 1710	IBM 1401, 1440, 1460, 1620, 1710
ASMB, ASBL, NSBL - Numeric op codes, used for 1900 Operating System Executive		No	Proprietary	ICL 1900	ICL 1900
GINerator mnemonic opcodes, used for GEORGE (operating system)		No	Proprietary	ICL 1900	ICL 1900
PLAN mnemonic opcodes, used for commercial 1900 programs		No	Proprietary	ICL 1900	ICL 1900
Single Address Assembly Language (SAAL)			Free	UNIVAC 1005	UNIVAC 1005
Sleuth			Free	UNIVAC 1107	EXEC, EXEC II, EXEC 8
Meta Assembler (MASM)			Free	UNIVAC 1100/2200 series	UNIVAC EXEC 8
UTMOST			?	UNIVAC III	UNIVAC III

Notes and references

^ The Yasm Modular Assembler Project
^ The Yasm Modular Assembler Project
^ COMPASS is a family of assemblers for disparate machines.
^ Autocoder is actually a family of assemblers for disparate machines.
^ SPS is actually a family of assemblers for disparate machines.

External links

List of assemblers running on S100 bus hardware, including CP/M hosted assemblers for 8080 and Z80

[1] The Yasm Modular Assembler Project

[2] The Yasm Modular Assembler Project

[3] COMPASS is a family of assemblers for disparate machines.

[4] Autocoder is actually a family of assemblers for disparate machines.

[5] SPS is actually a family of assemblers for disparate machines.

[1]

[2]

[3]

[4]

[5]

[1]

[6]

[2]

[3]

[4]

[5]