---
name: "regfiletype"
section: "1"
platform: "linux"
package: "regina"
version: "7.4.1-4"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/regfiletype"
---

# regfiletype(1)

Identify the formats of Regina data files

## NAME

regfiletype - Identify the formats of Regina data files

## SYNOPSIS

**regfiletype** *file ...*

**regfiletype** { **-v, --version** \| **-?, --help** }

## DESCRIPTION

This utility determines which file format a given Regina data file is in. You may pass multiple files on the command line; the format of each file will be written to standard output.

Only Regina's modern XML-based file formats are recognised (both compressed and uncompressed). In its very early years, Regina used an impenetrable and undocumented binary format; this was replaced with XML in 2002 (Regina 3.0), and support for this format was removed completely in 2013 (Regina 4.94). If you still need to recognise and/or read files in this ancient binary format, you will need to download Regina 4.93.

## OPTIONS

- **-v, --version**

  Show which version of Regina is being used, and exit immediately.

- **-?, --help**

  Display brief usage information, and exit immediately.

## MACOS USERS

If you downloaded a drag-and-drop app bundle, this utility is shipped inside it.  If you dragged Regina to the main Applications folder, you can run it as /Applications/Regina.app/Contents/MacOS/regfiletype.

## WINDOWS USERS

The command-line utilities are installed beneath the *Program Files* directory; on some machines this directory is called *Program Files (x86)*. You can start this utility by running c:\\Program Files\\Regina\\Regina 7.4.1\\bin\\regfiletype.exe.

## SEE ALSO

regconvert, regina-gui.

## AUTHOR

This utility was written by Benjamin Burton \<bab@maths.uq.edu.au\>. Many people have been involved in the development of Regina; see the users' handbook for a full list of credits.