Pace & Race Time Calculator

Method, assumptions & sources

Who this is for

Arithmetic conversions for recreational activity. Race prediction is an illustration for trained adults under comparable conditions.

How it works

Pace = elapsed time ÷ distance; speed = distance ÷ elapsed time. Exact mile = 1.609344 km. Race prediction uses T₂ = T₁ × (D₂/D₁)^exponent, default 1.06. Times are rounded once to whole seconds before formatting.

Keep in mind

• Race times are not guaranteed and extrapolation, especially to a marathon, may be optimistic.
• No training prescription or medical exercise clearance is generated.

Sources

• Riegel (1981): athletic records and human endurance (opens in a new tab)
• Blythe & Király (2016): performance prediction and the conventional 1.06 exponent (opens in a new tab)
• NIST: SI unit conversion factors (opens in a new tab)