# Factor

**Source:** https://factorcode.org

Factor programming language



![Factor programming language](logo.png)

# Why Factor

The **Factor programming language** is a [concatenative](http://www.concatenative.org/), stack-based programming language with [high-level features](http://concatenative.org/wiki/view/Factor/Features/The%20language) including dynamic types, extensible syntax, macros, and garbage collection. On a practical side, Factor has a [full-featured library](http://docs.factorcode.org/content/article-vocab-index.html), supports many different platforms, and has been extensively documented.

The implementation is [fully compiled](http://concatenative.org/wiki/view/Factor/Optimizing%20compiler) for performance, while still supporting [interactive development](http://concatenative.org/wiki/view/Factor/Interactive%20development). Factor applications are portable between all common platforms. Factor can [deploy stand-alone applications](http://concatenative.org/wiki/view/Factor/Deployment) on all platforms. Full [source code](https://github.com/factor/factor) for the Factor project is available under a [BSD license](https://factorcode.org/license.txt).

* [Learn more about Factor](https://concatenative.org/wiki/view/Factor)
* [Get started programming with Factor](https://concatenative.org/wiki/view/Factor/Learning)
* [Get answers to frequently-asked questions](https://concatenative.org/wiki/view/Factor/FAQ)
* [Read Factor documentation online](https://docs.factorcode.org/)
* [Learn about concatenative programming](https://concatenative.org/wiki/view/Concatenative%20language)
* [See some example programs](https://concatenative.org/wiki/view/Factor/Examples)
* [Report a bug](https://github.com/factor/factor/issues)
* Screenshots on [macOS](https://factorcode.org/factor-macos.png), [Windows](https://factorcode.org/factor-windows7.png)

```
USING: io kernel sequences ;  
  
4 <iota> [  
    "Happy Birthday " write  
    2 = "dear NAME" "to You" ? print  
] each
```

# Downloads

To download a binary, follow the link for the desired OS / CPU configuration. Binary packages are the recommended route for new users who wish to try Factor.

## Stable release: [0.101](https://re.factorcode.org/2025/12/factor-0-101-now-available.html)

| OS/CPU | Windows | macOS | Linux |
| --- | --- | --- | --- |
| x86 | [0.101](https://builds.factorcode.org/release?os=windows&cpu=x86.32) |  | [0.101](https://builds.factorcode.org/release?os=linux&cpu=x86.32) |
| x86-64 | [0.101](https://builds.factorcode.org/release?os=windows&cpu=x86.64) | [0.101](https://builds.factorcode.org/release?os=macos&cpu=x86.64) | [0.101](https://builds.factorcode.org/release?os=linux&cpu=x86.64) |

**Source code**:
[0.101](https://downloads.factorcode.org/releases/0.101/factor-src-0.101.zip)

## Development release

| OS/CPU | Windows | macOS | Linux |
| --- | --- | --- | --- |
| x86 | [2025-12-17](https://builds.factorcode.org/package?os=windows&cpu=x86.32) |  | [2026-02-11](https://builds.factorcode.org/package?os=linux&cpu=x86.32) |
| x86-64 | [2025-12-17](https://builds.factorcode.org/package?os=windows&cpu=x86.64) | [2026-02-09](https://builds.factorcode.org/package?os=macos&cpu=x86.64) | [2026-02-11](https://builds.factorcode.org/package?os=linux&cpu=x86.64) |

**Source code**: available via [github](https://github.com/factor/factor/) or [gitweb](https://gitweb.factorcode.org/) or [cgit](https://cgit.factorcode.org/).

Stable and development releases are built and uploaded by the [build farm](https://concatenative.org/wiki/view/Factor/Build%20farm). Follow [@FactorBuilds](https://twitter.com/FactorBuilds) on Twitter to receive notifications. If you're curious, take a look at the [build farm dashboard](https://builds.factorcode.org/dashboard). You can also [build Factor](https://concatenative.org/wiki/view/Factor/Building%20Factor) on your own platform from source.

## Older releases

[Download older releases](https://downloads.factorcode.org/releases/) from [Factor 0.29](https://downloads.factorcode.org/releases/0.29/) to the current release.

# Community

* [Join the mailing list](https://concatenative.org/wiki/view/Factor/Mailing%20list)
* [Join the Discord](https://discord.gg/QxJYZx3QDf)
* [Join the IRC channel](https://concatenative.org/wiki/view/Concatenative%20IRC%20channel)
* [Factor community blogs](https://planet.factorcode.org/)
* [Factor community pastebin](https://paste.factorcode.org/) - if you're in an IRC channel and want to share some code
* [Academic publications](https://concatenative.org/wiki/view/Concatenative%20language/Publications)