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Correlation and regression

Moderation Analysis Calculator

Test whether the effect of X on Y depends on one or two moderators. You get the interaction test, conditional effects at low, middle and high moderator values, the Johnson-Neyman region of significance and an interaction plot.

Free · No sign-upReplaces SPSS PROCESS macroWorks with your data
Updated · By Bibin Xavier

Data 250 × 9

Paste from Excel, or drop a CSV, TSV or Excel file here.
Example data 250 rows, 9 variables. Data stays in this browser tab.
Employeetext · 250 levelsLeadershipnumericTrustnumericEngagementnumericAutonomynumericTenure_YearsnumericPerformancenumericAgenumericFemalenumeric · coded
E0014.563.944.123.214.95.36281
E0024.423.024.353.12104.26431
E0034.824.944.784.2319.44.06210
E0044.654.083.533.375.44.22210
E0056.434.585.353.3110.96.12440
E0064.865.495.414.6115.54.72380
E0072.93.795.552.8412.24.86350
E0084.64.113.54.372.35.09390

Variables and options

Covariates (optional) 0 selected
Covariates enter every equation, as in PROCESS.
Results update automatically when you change an option.

Results

250 rows · example data
PROCESS model1Simple moderation
Sample size250
Bootstrap samples—percentile 95% CI
Standard errorsOLS

Conceptual diagram: Model 1

W: AutonomyX: LeadershipY: Performance
Table 1

Outcome: Performance

PredictorcoeffsetpLLCIULCI
constant5.69531.10955.133< .0013.51017.8806
Leadership-0.19320.2419-0.799.425-0.66960.2833
Autonomy-0.62800.2794-2.248.025-1.1784-0.0777
Leadership × Autonomy0.13970.06132.281.0230.01910.2604

Note. R = .3561, R² = .1268, MSE = 0.7087, F(3, 246) = 11.912, p < .001. Highest-order interaction test: Leadership × Autonomy: ΔR² = .0185, F(1, 246) = 5.202, p = .023.

Table 2

Conditional effects of Leadership at values of the moderator

AutonomyEffectsetpLLCIULCI
2.9890.22450.07992.810.0050.06720.3818
4.0350.37070.06315.877< .0010.24640.4949
5.0920.51830.09955.211< .0010.32240.7142

Note. Moderator values are the 16th, 50th and 84th percentiles.

Table 3

Johnson-Neyman significance region for Autonomy

Transition value% of sample below% of sample above
2.688510.489.6

Note. The effect of Leadership changes significance at these values of Autonomy (α = .05). Observed range: 1.09 to 7.00.

Conditional effect of Leadership across Autonomy

Interaction plot

Interpretation

The Leadership × Autonomy interaction is statistically significant and adds 1.85% to the explained variance in Performance. The effect of Leadership depends on Autonomy; read the conditional effects table and the Johnson-Neyman region to see where it is significant.

The Leadership × Autonomy interaction was significant, ΔR² = .018, F(1, 246) = 5.20, p = .023.

How to cite this tool

Using these results in a thesis, journal article, report or class assignment? Please cite this free tool so others can find it. It keeps the site free.

APA 7

Xavier, B. (2026). Moderation Analysis Calculator [Web application]. FreeStatisticalTools.com. https://freestatisticaltools.com/moderation-analysis-calculator/

BibTeX

@software{xavier_moderationanalysis_2026,
  author = {Xavier, Bibin},
  title = {Moderation Analysis Calculator},
  publisher = {FreeStatisticalTools.com},
  year = {2026},
  url = {https://freestatisticaltools.com/moderation-analysis-calculator/},
  note = {Web application}
}

Suggested sentence for your methods section: “The analysis was carried out with the free Moderation Analysis Calculator tool on FreeStatisticalTools.com (Xavier, 2026).”

What is moderation analysis?

Moderation analysis tests whether the effect of X on Y depends on a moderator. This tool runs Hayes’ PROCESS Model 1 (one moderator), Model 2 (two additive moderators) and Model 3 (three-way interaction), with conditional effects, the Johnson-Neyman technique and an interaction plot.

When to use moderation analysis

Use moderation analysis when theory says the strength or direction of an effect changes with a third variable. Model 1 has one moderator, Model 2 two additive moderators, and Model 3 a three-way interaction (moderated moderation).

Assumptions

  • Linear relationships and correctly specified causal ordering (X before M before Y), justified by theory or design.
  • Independent observations and, for OLS standard errors, constant residual variance (choose HC3 if this is doubtful).
  • No unmeasured confounding of the paths between mediators and the outcome.

How to set up your data

One row per case and one numeric column per variable. Code dichotomous variables 0/1. Moderators with two values are probed at those two values; continuous moderators at the 16th, 50th and 84th percentiles, or the mean ± 1 SD.

How to use this tool

  1. Enter your data. Paste columns from Excel, Google Sheets or SPSS with variable names in the first row, or upload a CSV or Excel file. The example data shows the expected layout.
  2. Choose the variables. Select the x (predictor), y (outcome), moderator w and covariates (optional).
  3. Set the options. Fill in process model, confidence level, moderator values and standard errors.
  4. Read the results. Results update automatically. Read the plain-English interpretation, then use Copy table to paste APA-style tables into Word and Copy for the results sentence.

How to report moderation analysis in APA style

Report the interaction coefficient with its test and ΔR², then the conditional effects or the Johnson-Neyman transition points.

Frequently asked questions

Should I mean-center my variables?

Centering only changes how the lower-order coefficients are interpreted; the interaction test is identical. PROCESS does not center by default, and neither does this tool.

What is the Johnson-Neyman technique?

It finds the moderator values at which the effect of X changes from significant to non-significant, so you do not depend on arbitrary low, middle and high values.

What is the difference between moderation and mediation?

A moderator changes the strength or direction of an effect. A mediator explains how or why the effect occurs.

Related tools

PROCESS is a macro for SPSS, SAS and R written by Andrew F. Hayes. This tool is an independent implementation of the published regression methods and model numbering (Hayes, 2022) and is not affiliated with, endorsed by or derived from the PROCESS software.

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