Free Online Meta-Analysis Tool - Meta-Mar 2026

Meta-Mar

Free public {meta-analysis platform}

Launch Meta-Mar Classic

Meta-Mar 5 is on its way

A new, open-source engine for meta-analysis: free for everyone, and built to work wherever you do research.

Free and open source. No accounts, no tokens, no paid plans. The code is open, the methods are documented, and every result can be reproduced.

A more capable statistical engine. Pairwise and single-group analyses (including prevalence), modern heterogeneity estimators and Hartung–Knapp inference, subgroups, meta-regression, and sensitivity diagnostics. In development: multilevel models for dependent effects, network meta-analysis, and umbrella reviews.

Use it your way. In the Meta-Mar web hub, directly through the API, or inside your own AI assistant, such as Claude, with Meta-Mar tools and skills: the AI explains, Meta-Mar computes. Run it locally, and your data never leaves your machine.

Until then, the current Meta-Mar stays free and available.

Meta-Mar Classic is a free-to-use platform for quantitative evidence synthesis.

It provides an interactive environment for meta-analysis of continuous, binary, correlation, and pre-calculated effect-size data. Analyses include fixed- and random-effects models, heterogeneity assessment, publication-bias diagnostics, sensitivity analysis, subgroup analysis, meta-regression, and interactive visualisations.

Statistical analyses are performed by a validated R-based analysis engine and are accessible through the web interface without installation, registration, or payment.

Meta-Mar is developed as scientific software for research, teaching, and reproducible evidence synthesis.

Used in Academic Teaching

Workshop participants at the University of Extremadura computer lab
Workshop participants at the University of Extremadura computer lab
Instructor-led demonstration of Meta-Mar v4.0.2 during the workshop
Instructor-led demonstration of Meta-Mar v4.0.2 during the workshop

Workshop in evidence synthesis — Department of Nursing, Faculty of Nursing and Occupational Therapy, University of Extremadura, Cáceres (May 2026)
20 participants completing 5–6 individual meta-analyses each across a three-day course on Synthesis of Evidence in Health Sciences II.

Hands-on Meta-Mar workshop during a PhD meta-analysis course
Hands-on workshop during a PhD meta-analysis course
Live demonstration: bubble plot for meta-regression analysis
Live demonstration: bubble plot for meta-regression analysis

PhD course in meta-analysis — Center for Health Technology Assessment, Semmelweis University, Budapest (January 2026)
~30 concurrent users running real-time analyses with AI guidance tailored to each study.

Case Studies

Meta-Mar Workshop: End-to-end meta-analysis tutorials using real clinical data (e.g., MIMIC-IV). From study design and cohort extraction to statistical analysis and AI-generated interpretation.

Coming soon.

Meta-Mar Privacy Policy

Effective date: 11 November 2026

This policy covers www.meta-mar.com and Meta-Mar Classic, the current analysis application. Meta-Mar is free to use. It needs no account and no payment, and it does not use analytics or advertising trackers.

1. Controller

Ashkan Beheshti Hamedani
c/o Philipps-Universität Marburg, Fachbereich Psychologie, AG Klinische Kinder- und Jugendpsychologie
Gutenbergstr. 18, 35037 Marburg, Germany
Email: ashkan.beheshti@staff.uni-marburg.de
See also the Impressum.

2. What happens to your data

2.1 Meta-Mar Classic analysis

  • Meta-Mar Classic runs on shinyapps.io, a hosting service operated by Posit (USA). The data you upload is processed there in your session with R (the meta and metafor packages).
  • Your data is used only to compute and display your results. It is not linked to any person or account and is not analysed for any other purpose.
  • Please do not upload personal or confidential data. Meta-analysis normally needs only aggregate study-level data.

2.2 Optional AI features (Classic)

  • The AI assistant and AI reports are used only if you choose to use them. Statistical analysis never requires them.
  • If you use them, your messages and, for a report, your analysis results are sent to OpenAI, our AI processor, to generate the answer. OpenAI may process this data in the United States.
  • Do not enter or analyse sensitive information when using the AI features.

2.3 Website visits and hosting

  • This website is hosted by Railway. Like any web server, the hosting infrastructure may process technical data such as IP address, date and time, and requested page in server logs, to deliver the site and keep it secure (legitimate interest, Art. 6(1)(f) GDPR). Railway may process this data in the United States. The analysis application is hosted separately on shinyapps.io (Posit), which may also log such technical data.
  • The site sets no cookies and loads no third-party analytics, fonts or advertising scripts.

2.4 Analytics

There are none. Google Analytics and similar tools have been removed.

2.5 Development-priorities survey

The survey on the Contribute page stores only which priorities were ticked and a timestamp. It stores no name, email address or IP address, and it can be answered anonymously. Aggregated counts are public on the survey-results page. The counts are held in a managed database service (Supabase).

3. Your rights

Under the GDPR you have the right of access, rectification, erasure, restriction of processing, data portability and objection (Arts. 15–21), and the right to withdraw consent at any time. Because Classic holds no account data, we can usually identify you in our systems only if you give us specifics (for example the time of a request). You also have the right to lodge a complaint with a supervisory authority, in particular in the EU member state where you live or work or where an alleged infringement took place. The authority responsible for the controller is the Hessian Commissioner for Data Protection and Freedom of Information (Der Hessische Beauftragte für Datenschutz und Informationsfreiheit), Wiesbaden.

4. Coming with Meta-Mar 5

The Meta-Mar 5 engine is designed to be stateless: requests are computed and not stored. It will also run locally on your own computer or institutional server, so your data never has to leave your machine.

5. Contact

For privacy questions or requests, contact: ashkan.beheshti@staff.uni-marburg.de

Impressum

Provider

Ashkan Beheshti Hamedani
c/o Philipps-Universität Marburg
Fachbereich Psychologie, AG Klinische Kinder- und Jugendpsychologie
Gutenbergstr. 18
35037 Marburg
Germany

Contact

Email: ashkan.beheshti@staff.uni-marburg.de

About this project

Meta-Mar is a free academic software project for meta-analysis, developed and maintained by Ashkan Beheshti Hamedani.

Licences

Source code: AGPL-3.0 (see the LICENSE file in each repository). Website texts and documentation: CC BY 4.0 (see CONTENT-LICENSE). © 2020–2026 Ashkan Beheshti.

See also the Privacy Policy.

Contribute to Meta-Mar

Help shape the platform's future through feedback and community engagement.

Development Priorities

Which areas matter most to you? Select all that apply:

No personal data collected View results

Other Ways to Help

  • Cite — Reference Meta-Mar in your publications
  • Report — Submit bugs or ideas via GitHub Issues
  • Share — Recommend to colleagues who might benefit
  • Feedback — Email contact@meta-mar.com

Citation

If you use Meta-Mar in your research, please cite the preprint and/or the software as appropriate.

Paper (Preprint)

Beheshti, A., Sazmand, H., Chavanon, M.-L., & Christiansen, H. (2026). Meta-Mar: An AI-assisted web platform for accessible and rigorous meta-analysis. OSF Preprints. https://doi.org/10.31222/osf.io/psw4x_v1

Software

@software{beheshti2026metamar,
  author    = {Beheshti, Ashkan and Sazmand, Hassan and Chavanon, Mira-Lynn and Christiansen, Hanna},
  title     = {Meta-Mar: An AI-Integrated Web Platform for Meta-Analysis},
  year      = {2026},
  url       = {https://www.meta-mar.com},
  version   = {4.0.2}
}

Software paper under review at the Journal of Open Source Software (JOSS).