---
name: "kdiff3"
section: "1"
platform: "linux"
package: "kdiff3"
version: "1.12.6-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/kdiff3"
---

# kdiff3(1)

Tool for Comparison and Merge of Files and Folders

## NAME

kdiff3 - Tool for Comparison and Merge of Files and Folders

## SYNOPSIS

**kdiff3** \[**-u, --ignore**\] \[**--query**\] \[**--html**\] \[**--abort**\] \[**-m, --merge**\] \[**-b, --base** *file*\] \[**-o, --output** *file*\] \[**--out** *file*\] \[**--noauto**\] \[**--auto**\] \[**--L1** *alias1*\] \[**--L2** *alias2*\] \[**--L3** *alias3*\] \[**-L, --fname** *alias*\] \[**--cs** *string*\] \[**--confighelp**\] \[**--config** *file*\] \[*File1*\] \[*File2*\] \[*File3*\]

## DESCRIPTION

Compares two or three input files or folders.

## OPTIONS

- **-u, --ignore**

  Ignored. (User defined.)

- **--query**

  Ignored. (User defined.)

- **--html**

  Ignored. (User defined.)

- **--abort**

  Ignored. (User defined.)

- **-m, --merge**

  Merge the input.

- **-b, --base** *file*

  Explicit base file. For compatibility with certain tools.

- **-o, --output** *file*

  Output file. Implies -m. e.g.: -o newfile.txt

- **--out** *file*

  Output file, again. (For compatibility with certain tools.)

- **--auto**

  No GUI if all conflicts are auto-solvable. (Needs **-o** *file*)

- **--noauto**

  Ignore --auto and always show GUI.

- **--L1** *alias1*

  Visible name replacement for input file 1 (base).

- **--L2** *alias2*

  Visible name replacement for input file 2.

- **--L3** *alias3*

  Visible name replacement for input file 3.

- **-L, --fname** *alias*

  Alternative visible name replacement. Supply this once for every input.

- **--cs** *string*

  Override a config setting. Use once for every setting. e.g.: **--cs** *AutoAdvance=1*.

- **--confighelp**

  Show list of config settings and current values.

- **--config** *file*

  Use a different config file.

*File1*

file1 to open (base, if not specified via --**base**)

*File2*

file2 to open

*File3*

file3 to open

## SEE ALSO

More detailed user documentation is available from **help:/kdiff3** (either enter this URL into Konqueror, or run **khelpcenter** *help:/kdiff3*).

[kf6options(7)](/kf6options/7.md)

[qt6options(7)](/qt6options/7.md)

## AUTHORS

This manual page was written by Burkhard Lück \<lueck@hube-lueck.de\>.

## AUTHOR

**Burkhard Lueck** \<lueck@hube-lueck.de\>

KDiff3 man page.