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Geography

Watershed Drainage Area Calculator

Estimate the drainage area of a watershed from its length, average width, and a shape factor. Used by hydrologists and civil engineers to assess runoff, flood risk, and water resource capacity.

Fill in the required fields to see your result.
Geography

Earthquake Distance Calculator

Estimate the distance from a seismograph station to an earthquake epicenter using the arrival time difference between P and S seismic waves. Useful for seismology education and rapid preliminary epicenter location.

Fill in the required fields to see your result.

Key differences

Watershed Drainage Area CalculatorEarthquake Distance Calculator
CategoryGeographyGeography
Inputs required52
ResultAnnual Runoff Volume (million m³)Epicenter Distance (km)
What it doesEstimate the drainage area of a watershed from its length, average width, and a shape factor. Used by hydrologists and civil engineers to assess runoff, flood risk, and water resource capacity.Estimate the distance from a seismograph station to an earthquake epicenter using the arrival time difference between P and S seismic waves. Useful for seismology education and rapid preliminary epicenter location.