Compare calculators

Both calculators run independently — change the inputs on either side to compare results.

Marathon Finish Time Predictor

Predicts your marathon finish time from your average training pace and a fitness factor adjustment. Ideal for race-day planning and setting realistic time goals before a 26.2-mile event.

Average Training Pace (min/km)

Fitness Factor

Fill in the required fields to see your result.

Sports

Body Fat Percentage Calculator

Estimates body fat percentage from waist, neck, and hip circumferences using the U.S. Navy tape-measure method. Use it to track changes in body composition without calipers or expensive lab scans.

Gender

Waist Circumference (cm)

Neck Circumference (cm)

Hip Circumference (Women) (cm)

Fill in the required fields to see your result.

Key differences

	Marathon Finish Time Predictor	Body Fat Percentage Calculator
Category	Sports	Sports
Inputs required	2	4
Result	Predicted Marathon Time (hours)	Body Fat Percentage (%)
What it does	Predicts your marathon finish time from your average training pace and a fitness factor adjustment. Ideal for race-day planning and setting realistic time goals before a 26.2-mile event.	Estimates body fat percentage from waist, neck, and hip circumferences using the U.S. Navy tape-measure method. Use it to track changes in body composition without calipers or expensive lab scans.