Plan a race
Find my pace
Know my fitness
Guides
All tools
Every calculator, chart, and planning tool — in one place.
Plan a race
Pick a race
Choose from 50+ marathons
Race predictor
Estimate finish time from a past result
Find my pace
Pace calculator
Solve for pace, time, or distance
Marathon pace calculator
Splits for 26.2 miles / 42.2 km
Half marathon pace calculator
Splits for 13.1 miles / 21.1 km
5K pace calculator
Splits for 5 kilometres
Pace chart
Reference table for common paces & finish times
Unit converter
min/km, min/mi, km/h, mph
Distance converter
km ↔ miles — for race entries and GPS units
Pace converter
Quick pace unit conversions
Know my fitness
Heart rate zones
Train at the right intensity
VDOT & training paces
Soon
Jack Daniels formula
My profile
Soon
Save your personal bests
Guides
Sub-3 marathon pace
Everything for a 2:59:59
5K pacing strategy
Go out right, finish strong
Boston Marathon
Soon
Course breakdown & split targets