---
name: "rz-asm"
section: "1"
platform: "linux"
package: "rizin"
version: "0.8.2-2"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/rz-asm"
---

# rz-asm(1)

rizin assembler and disassembler tool

## NAME

**rz-asm** – rizin assembler and disassembler tool

## SYNOPSIS

**rz-asm** \[**-ABCdDeIEhjLpqrvxw**\] \[**-a** *arch*\] \[**-b** *bits*\] \[**-m** *plugin*\] \[**-c** *CPU*\] \[**-O** *file*\] \[**-o** *addr*\] \[**-@** *addr*\] \[**-f** *file*\] \[**-F** *in:out*\] \[**-i** *len*\] \[**-k** *kernel*\] \[**-s** *syntax*\] \[**-l** *len*\]

## DESCRIPTION

This command is part of the Rizin project.

This tool uses RzAsm to assemble and disassemble files or hexpair strings. It supports a large list of architectures which can be listed using the -L flag.

- **-a** *arch*

  Set architecture to assemble/disassemble (see -L)

- **-A**

  Show analysis information from given hexpairs

- **-b** *bits*

  Set CPU register size (8, 16, 32, 64) (RZ\_ASM\_BITS)

- **-B**

  Binary input/output (-l is mandatory for binary input)

- **-c** *CPU*

  Select specific CPU (depends on the arch)

- **-C**

  Output in C format

- **-d,** **-D**

  Disassemble from hexpair bytes (-D show hexpairs)

- **-e**

  Use big endian instead of little endian

- **-I**

  Display lifted RzIL code (same input as in -d, IL is also validated)

- **-E**

  Display ESIL expression (same input as in -d)

- **-f** *file*

  Read data from file

- **-F** *in:out*

  Specify input and/or output filters (att2intel, x86.pseudo, ...)

- **-h,** **-hh**

  Show usage help message, hh for long

- **-i** *len*

  Ignore N bytes of the input buffer

- **-j**

  Output in JSON format

- **-k** *kernel*

  Select operating system (linux, windows, darwin, ..)

- **-l** *len*

  Input/Output length

- **-L**

  List asm plugins: (a=asm, d=disasm, A=analyze, e=ESIL)

- **-m** *plugin*

  List supported CPUs for the chosen plugin

- **-o,** **-@** *addr*

  Set start address for code (default 0)

- **-O** *file*

  Output file name (rz-asm -Bf a.asm -O a)

- **-p**

  Run SPP over input for assembly

- **-q**

  Quiet mode

- **-r**

  Output in rizin commands

- **-s** *syntax*

  Select syntax (intel, att)

- **-v**

  Show version information

- **-x**

  Use hex dwords instead of hex pairs when assembling

- **-w**

  Describe opcode

## Directives

- **.intel\_syntax**

  Use Intel syntax rather than AT&T

- **.att\_syntax**

  Use AT&T syntax rather than Intel

- **.align** *number*

  Set the code or data alignment

- **.arch** *name*

  Set the code architecture

- **.arm**

  Set the ARM mode (as opposed to Thumb) for ARM architecture

- **.ascii** *string*

  Define the ASCII string

- **.asciz** *string*

  Define the zero-ending ASCII string

- **.bits** *number*

  Define the code bitness

- **.big\_endian**

  Set the BE (big endian) byte order

- **.cpu** *name*

  Set the CPU for the chosen architecture

- **.data**

  Mark the start of the data section

- **.endian** *1\|0*

  Set the endianness (the byte order) - 1 is BE, 0 is LE

- **.equ** *name* *value*

  Define the constant

- **.fill** *repeat,size,value*

  Fill the data with the repeating value pattern

- **.hex** *data*

  Define the data in hexadecimal format

- **.incbin** *filename*

  Include binary file

- **.int16** *number*

  Define 16-bit integer

- **.int32** *number*

  Define 32-bit integer

- **.int64** *number*

  Define 64-bit integer

- **.kernel** *name*

  Set the kernel for syscalls

- **.little\_endian**

  Set the LE (little endian) byte order

- **.org** *value*

  Set the value of the PC (Program Counter) register

- **.os** *name*

  Set the operating system for syscalls

- **.short** *number*

  Define 16-bit integer

- **.string** *string*

  Define the ASCII string

- **.text**

  Mark the start of the text section

- **.thumb**

  Set the Thumb mode (as opposed to ARM) for ARM architecture

## ENVIRONMENT

RZ\_ARCH:      e asm.arch - architecture to assemble/disassemble (same as rz-asm -a)

RZ\_ASM\_ARCH:  architecture to assemble/disassemble (same as rz-asm -a)

RZ\_ASM\_BITS:  cpu register size (8, 16, 32, 64) (same as rz-asm -b)

RZ\_BITS:      e asm.bits - cpu register size (8, 16, 32, 64) (same as rz-asm -b)

RZ\_DEBUG:     if defined, show error messages and crash signal0

RZ\_NOPLUGINS: do not load shared plugins (speedup loading)0

## EXAMPLES

Assemble opcode:

**rz-asm** **-a** **x86** **-b** **32** *'mov* *eax,* *33'*

Disassemble opcode:

**rz-asm** **-d** **90**

## SEE ALSO

[rizin(1)](/rizin/1.md), [rz-find(1)](/rz-find/1.md), [rz-hash(1)](/rz-hash/1.md), [rz-bin(1)](/rz-bin/1.md), [rz-diff(1)](/rz-diff/1.md), [rz-gg(1)](/rz-gg/1.md), [rz-run(1)](/rz-run/1.md), [rz-ax(1)](/rz-ax/1.md),

## AUTHORS

pancake \<pancake@nopcode.org\>

byteninjaa0