Frequency Analysis

Compare multiple probability distributions with comprehensive goodness-of-fit metrics

Data Upload
Upload Annual Maximum Series

Upload a CSV file containing annual maximum values (rainfall or flood data)

Click to upload or drag & drop file here

CSV format only

Select Distributions
Fitting Method

Choose how the parameters of every selected distribution are estimated.

The chosen method drives all parameters, return levels, plots and the report. Under L-moments, AIC/BIC are shown for reference only — compare fits using KS, RMSE and the Q–Q / P–P plots.

Goodness-of-Fit Metrics
  • AIC/BIC: Lower values indicate better fit (likelihood-based; reference only under L-moments)
  • KS Test: Lower statistic, higher p-value
  • RMSE: Lower values indicate better fit
  • Chi-Square: Lower statistic, higher p-value
Data Summary

Upload data and process to visualize frequency analysis plots

Analysis tables will appear here

Return period tables will appear here