All tools

Every calculator, chart, and planning tool — in one place.

Plan a race

Choose from 50+ marathons

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

Reference table for common paces & finish times

min/km, min/mi, km/h, mph

Distance converter

km ↔ miles — for race entries and GPS units

Quick pace unit conversions

Know my fitness

Heart rate zones

Train at the right intensity

VDOT & training pacesSoon

Jack Daniels formula

My profileSoon

Save your personal bests

Guides

Sub-3 marathon pace

Everything for a 2:59:59

5K pacing strategy

Go out right, finish strong

Boston MarathonSoon

Course breakdown & split targets