Statistical Calculators
These free calculators are hosted on Subthesis, our companion site for statistical computation. Each tool lets you enter your values and get results instantly — no software to install, no sign-up required. Use the tutorials here on Stats for Scholars to learn when and why to use each test, then head to Subthesis to run your numbers.
Effect Size Calculator
Calculate Cohen's d, Hedges' g, and other effect size measures for your study.
Use Calculator →Sample Size & Power Analysis Calculator
Determine the statistical power of your study or the sample size you need.
Use Calculator →Sample Size & Power Analysis Calculator
Find out how many participants you need for adequate statistical power.
Use Calculator →Effect Size Calculator
Calculate effect sizes (Cohen's d, Hedges' g) for your t-test results.
Use Calculator →Effect Size Calculator
Calculate eta-squared and other effect sizes for your ANOVA results.
Use Calculator →Subthesis Research Tools
Browse free research tools for statistical analysis, methodology, and more.
Use Calculator →Subthesis Research Tools
Browse free research tools for statistical analysis, methodology, and more.
Use Calculator →Subthesis Research Tools
Browse free research tools for statistical analysis, methodology, and more.
Use Calculator →Reliability Calculator
Calculate Cronbach's alpha, inter-rater reliability, and other reliability measures.
Use Calculator →