Two-Way ANOVA Calculator

Evaluate whether a measurement is affected by two categorical factors and whether the factors interact. This tool supports two-way ANOVA with replication and two-way ANOVA without replication, along with CSV upload, example data, manual entry, charts, downloadable results, and a standardized Stat-Forge Study Report.

Data Input

CSV format should include one column for Factor A, one column for Factor B, and one numeric measurement column. Each Factor A × Factor B combination should be present. Replicated data can estimate the interaction term; one observation per cell is analyzed as two-way ANOVA without replication.

Upload CSV

Significance Level

Factor A Column

Factor B Column

Measurement Column

Manual Entry

Results

Two-Way ANOVA Table

Factor A Summary

Factor B Summary

Cell Means

Interaction Plot

Main Effects Plot

Interaction Classification

Effect Size / Practical Significance

Variance Contribution Chart

Assumption Diagnostics

Residuals vs Fitted Values

Residual Normal Probability Plot

Two-Way ANOVA Study Report

Generate a printable report with factor-effect classification, interaction classification, effect sizes, variance contribution, assumption diagnostics, residual plots, ANOVA table, cell means, engineering interpretation, conclusion, and criteria reference.

How to Use This Tool

Use two-way ANOVA when the response may depend on two categorical inputs such as machine and shift, material and temperature, supplier and inspection method, or line and operator. Review the interaction term first. A significant interaction means the effect of one factor changes depending on the level of the other factor.