Freedom251 › Statistical Analysis Software
G*Power
by G*Power
What G*Power is
G*Power is a free desktop program for statistical power analysis. It computes power for many t, F, χ², and z tests, along with some exact tests. The software can calculate effect sizes and display power-analysis results graphically. Its tutorial covers a priori, post-hoc, and compromise analyses, and presents examples from psychological research. Statistical tests, regression models, and scripting support are listed. G*Power runs locally on Windows and macOS, and the makers say the versions do not communicate with servers. The Windows installer may download Microsoft Visual C++ runtime libraries if needed. The Windows download is version 3.1.9.7 for Windows XP, Vista, 7, 8, 10, and 11. The Mac download is version 3.1.9.6 for Mac OS X 10.7 to 26 and is compiled for Intel processors. It costs nothing and is available for commercial use. Commercial distribution is prohibited, and redistribution through another channel requires permission from the authors.
Who it suits
It suits students, researchers, and analysts needing local power calculations, effect sizes, regression models, or scripts. The tutorial’s examples are aimed at general power analysis, including psychological research.
What it does well
- Free for commercial and non-commercial users
- Covers many common statistical tests
- Calculates and graphs effect sizes
- Runs locally on Windows and macOS
- Includes scripting support
What to know first
- Commercial distribution is prohibited
- Mac download is compiled for Intel processors
- Windows installer may download runtime libraries
- Makers provide no security documentation
Limits
G*Power is free, but commercial distribution is prohibited and redistribution through another channel requires permission from the authors. The Mac version is compiled for Intel processors; the Windows installer may download Microsoft Visual C++ runtime libraries if needed.
Plans
| Plan | Billed and limits | Price |
|---|---|---|
| Free | Available to everyone, including commercial users · Local desktop software for Windows and macOS | Free |
| G*Power | Free for everyone, including commercial use · Commercial distribution prohibited | Free |
As gpower.hhu.de lists them, read 20 Sept 2026. The maker's own page has the final word.
Getting started
- Open the G*Power website
- Choose the Windows or macOS download
- Install the desktop program for your operating system
- Run G*Power locally
- Select an analysis and enter the required values
Verdict
G*Power offers broad, local statistical power analysis at no cost. Users should note its distribution restrictions, platform versions, and the absence of provided security documentation.
Questions
How much does G*Power cost?
G*Power costs nothing. It is free for everyone, including commercial users.
Which operating systems are supported?
G*Power supports Windows and macOS. The Windows download is version 3.1.9.7, while the Mac download is version 3.1.9.6.
Does G*Power run online?
Both versions run locally and do not communicate with servers, except that the Windows installer may download Microsoft Visual C++ runtime libraries if needed.
What analyses does G*Power perform?
It computes power analyses for many t, F, χ², and z tests and some exact tests. It also supports effect sizes, regression models, scripting, and graphical power results.
Can a business redistribute G*Power?
Commercial use is allowed, but commercial distribution is prohibited. Redistribution through another channel requires permission from the authors.
Who makes G*Power?
The maker is G*Power, headquartered in Düsseldorf, Germany.
Facts from G*Power's own pages
- Analysis types
- The tutorial describes a priori, post-hoc, and compromise power analyses. · psychologie.hhu.de, 11 Oct 2026
- Deployment
- both · psychologie.hhu.de, 20 Sept 2026
- Distribution limit
- Redistributing G*Power through another channel requires permission from the authors, and commercial distribution is prohibited. · psychologie.hhu.de, 11 Oct 2026
- Effect sizes
- The software can compute effect sizes and display power analysis results graphically. · psychologie.hhu.de, 11 Oct 2026
- Free plan
- Yes · psychologie.hhu.de, 20 Sept 2026
- Headquarters
- Düsseldorf, Germany · gpower.hhu.de, 28 Sept 2026
- Intended audience
- The tutorial presents G*Power as a general power analysis program and illustrates its use with psychological research examples. · psychologie.hhu.de, 11 Oct 2026
- Local operation
- The official page says both versions run locally and do not communicate with servers, aside from the Windows installer attempting to download Microsoft Visual C++ runtime libraries if needed. · psychologie.hhu.de, 11 Oct 2026
- Mac version
- The Mac download is version 3.1.9.6 for Mac OS X 10.7 to 26 and is compiled for Intel processors. · psychologie.hhu.de, 11 Oct 2026
- Platforms
- The official page offers separate downloads for Windows and Mac OS X. · psychologie.hhu.de, 11 Oct 2026
- Privacy
- The update mailing list states that email addresses are used only to send update notices and are not shared with others. · psychologie.hhu.de, 11 Oct 2026
- Purpose
- G*Power computes statistical power analyses for many t, F, χ², z, and some exact tests. · psychologie.hhu.de, 11 Oct 2026
- Regression models
- Yes · psychologie.hhu.de, 20 Sept 2026
- Scripting support
- Yes · psychologie.hhu.de, 20 Sept 2026
- Security documentation
- The makers state that they do not provide license agreements, security documentation, or similar documents. · psychologie.hhu.de, 11 Oct 2026
- Statistical tests
- The tutorial demonstrates power analyses for t-tests, F-tests, and χ²-tests. · psychologie.hhu.de, 11 Oct 2026
- Support
- The makers invite users to email them to report bugs, usage difficulties, or suggestions for future versions. · psychologie.hhu.de, 11 Oct 2026
- Windows version
- The Windows download is version 3.1.9.7 and is listed for Windows XP, Vista, 7, 8, 10, and 11. · psychologie.hhu.de, 11 Oct 2026
Where G*Power stands on Freedom251
- Statistical Analysis Software#32 of 106