---
name: "fastbase64.coreutils"
section: "1"
platform: "linux"
package: "simdutf"
version: "9.2.2-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/fastbase64.coreutils"
---

# fastbase64.coreutils(1)

base64 encode/decode data and print to standard output (coreutils compatible)

## NAME

fastbase64.coreutils - base64 encode/decode data and print to standard output (coreutils compatible)

## SYNOPSIS

**fastbase64.coreutils** \[*OPTIONS*...\] \[*INPUTFILE*\]

## DESCRIPTION

**fastbase64.coreutils** encodes or decodes base64 data using the high-performance simdutf library, with options compatible with GNU coreutils base64, plus clearly marked fastbase64-specific extensions. By default, it encodes binary input to base64 output. On large files, it can be several times faster than standard base64 tools.

**fastbase64 extension (not present in GNU coreutils base64):** If a second filename is provided, it is used as the output file. Otherwise, output goes to standard output. The **-o** option takes precedence over positional output file.

## OPTIONS

- **-b, --break=*NUM***

  synonym to --wrap. (not in GNU coreutils base64)

- **-w, --wrap=*NUM***

  Wrap encoded lines after *NUM* characters (default 76). Use 0 to disable line wrapping.

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

  Decode input.

- **-e, --encode**

  Encode input (default).

- **--ignore-garbage**

  When decoding, ignore non-alphabet characters.

- **-i, -n, --noerrcheck**

  fastbase64 extension (not present in GNU coreutils base64): when decoding, ignore non-alphabet characters (same as --ignore-garbage).

- **-h, --help**

  Display help message and exit.

- **-o, --output=*FILE***

  fastbase64 extension (not present in GNU coreutils base64): output file (default: "-" for stdout).

- **--version**

  Output version information and exit.

## EXAMPLES

- Encode a file:

  **fastbase64.coreutils myfile.txt**

- Decode base64 data ignoring garbage:

  **fastbase64.coreutils -d -i \< encoded.txt**

## SEE ALSO

[**base64**(1)](/base64/1.md), [**fastbase64**(1)](/fastbase64/1.md)

## AUTHOR

Written by the simdutf development team.