PACECALC · iOS App

Treadmill Calculator

Speed plus incline equals outdoor-equivalent pace. We use the published grade-cost curve, not a linear extrapolation.

UNITS
Treadmill speed
mph
Incline1.0%
0%5%10%15%

OUTDOOR-EQUIVALENT PACE
6:13
min/mi·3:52 min/km
Treadmill pace · km3:44
Treadmill pace · mi6:00
Speed · km/h16.1
Speed · mph10.0
METHODOLOGY

How this calculator works

  1. 1% treadmill grade equivalence

    Setting a treadmill to 1% incline most closely matches the metabolic cost of outdoor running at the same pace, mainly because there is no air resistance indoors. PaceCalc uses this as the default conversion; the calculator also handles steeper inclines where the grade-cost curve becomes nonlinear.

    A. M. Jones, J. H. Doust, "A 1% treadmill grade most accurately reflects the energetic cost of outdoor running," Journal of Sports Sciences, vol. 14, no. 4, 1996, pp. 321–327.

NOTES
  • The 1% rule applies most accurately at paces between roughly 4:30/km and 7:00/km on flat treadmills. Steeper inclines (3 %+) have a steeper energetic cost; we apply a published grade-cost curve, not a linear extrapolation.
FAQ

Frequently asked

Is treadmill running easier than outdoor running?
Yes, treadmills lack wind resistance and assist your stride with belt movement. Setting a 1% incline roughly approximates outdoor effort on flat terrain. Our calculator accounts for incline when converting to outdoor-equivalent pace.
How does treadmill incline affect effort?
Each 1% incline increase adds roughly 3-4% to your effort. Running at 10 km/h with 5% incline feels like running significantly faster on flat ground. The calculator uses grade adjustment formulas to compute the equivalent outdoor pace.
What treadmill speed equals a 5:00/km pace?
A 5:00/km pace equals 12.0 km/h (7.5 mph). Use our speed table to quickly look up any treadmill speed and its equivalent pace in both metric and imperial units.
Should I set the treadmill to 1% incline?
Research suggests 1% incline compensates for the lack of air resistance at speeds above ~10 km/h. For slower paces, 0% is fine. Our calculator lets you see the exact effort difference.
How do I convert mph to min/mile on a treadmill?
Divide 60 by the mph speed. For example, 6.0 mph = 60/6 = 10:00/mi. For km/h to min/km, divide 60 by the km/h speed. Our table shows all conversions at a glance.