PB predictor and pace calculator
Estimate a finish time from current form, or calculate exact pace, splits and a manual cutoff plan.
Pace charts by distance
Read a finish-time table, choose a target and print or share your kilometre or mile splits.
Performance prediction
Enter a recent result and the race you are targeting. We convert your current form to an equivalent finish time. Course energy estimates help compare terrain; they do not yet provide a validated adjustment to your finish time.
Pace, splits and cutoff arithmetic
Convert a target time or pace into an even-pace plan for distances up to 1,000 km. These figures are arithmetic, not a prediction of what you can achieve. The separate predictor above estimates equivalent performance from a recent result.
Compare marathon course models
Estes Park Marathon and Half Marathon
Modelled energy change -4.6%.
Montana Marathon (Billings)
Modelled energy change -2.5%.
Windermere Marathon (Spokane)
Modelled energy change -0.5%.
Reims Champagne Run Marathon
Modelled energy change -0.4%.
Maratona do Funchal (Funchal Marathon)
Modelled energy change -0.4%.
Generali Genève Marathon
Modelled energy change -0.3%.
Belfast City Marathon
Modelled energy change -0.1%.
Hoag OC Marathon Running Festival
Modelled energy change -0.1%.
Why a course-adjusted predictor
Generic predictors assume every course is flat. When a race has a verified GAP profile, this tool uses that measured gradient profile so a target with 300 m of climb is predicted slower than a pancake-flat PB course.