Uses the ACSM running equation: VO₂ = 0.2 × speed + 0.9 × speed × grade + 3.5 — more personalised than the usual "about 60–70 kcal per km" rule of thumb.
Frequently Asked Questions
Why does my watch show a different number?
Each vendor uses its own algorithm, often heart-rate based. Both this and your watch are estimates.
Gross vs net calories?
Gross includes resting metabolism; net subtracts what you would have burned anyway (about 1.2 kcal/min depending on body mass).
Should I use this for fat loss?
Only as a reference. Total energy balance and diet matter far more than a single session’s burn.
Gear runners ask about
GPS running watch
Pace, laps and alerts on your wrist
Chest strap heart-rate monitor
More reliable than wrist-based HR
Race day running shoes
Lightweight shoes for tempo and race pace
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