How trackers count floors
Watches and phones that count floors use a barometer, which senses small changes in air pressure as you go up. Garmin, for example, counts one floor for every 3 m (10 ft) of height gained. That is a height, not a number of stairs, so a steep stair and a shallow one both give one floor for the same climb.
Because floors come from height gained, walking up a hill or a ramp counts too, and going down does not add floors climbed. Our browser step counter does not use a barometer and does not count floors; it counts the steps you take, including steps on stairs, from your phone's motion sensor.
Steps per floor at common riser heights
A riser is the vertical height of one stair. Building rules set a maximum. In England, Approved Document K allows up to 22 cm for private stairs in homes and 17 cm for general access stairs in public buildings. In the United States, the International Residential Code allows up to 7 3/4 in (19.6 cm) in homes.
Dividing 3 m by the riser height gives the stair steps per tracker floor. This is a calculation, not a survey of real buildings: actual floor heights vary.
| Riser height | Steps per 3 m floor | Where this riser height applies |
|---|---|---|
| 17 cm | 18 | Upper limit for general access stairs in England |
| 19.6 cm | 16 | Upper limit for homes under the US International Residential Code (7 3/4 in) |
| 22 cm | 14 | Upper limit for private stairs in homes in England |
Flights vs floors
A flight is one unbroken run of stairs between landings. One storey of a building is often split into two flights with a landing, so a flight may be only half a floor.
In England, Approved Document K limits a general access stair to 12 risers per flight in most cases, or 16 where space is tight, and a utility stair to 16. Homes follow different rules. So a single flight in a public building is rarely more than 12 to 16 steps, while a full floor is usually more.
Stairs vs walking: effort and calories
The Compendium of Physical Activities lists the energy cost of activities in METs, multiples of your resting energy use. Climbing stairs costs far more than walking on the flat, and going down costs less than going up.
Calories per minute below use the standard conversion (METs x 3.5 x body weight in kg / 200) for a 70 kg adult. They are estimates.
| Activity | METs | kcal per minute |
|---|---|---|
| Descending stairs | 3.5 | 4.3 kcal |
| Walking, 2.8 to 3.4 mph (4.5 to 5.5 km/h), moderate | 3.8 | 4.7 kcal |
| Walking, 3.5 to 3.9 mph (5.6 to 6.3 km/h), brisk | 4.8 | 5.9 kcal |
| Stair climbing, slow pace | 4.5 | 5.5 kcal |
| Stair climbing, general | 6.8 | 8.3 kcal |
| Stair climbing, fast pace | 9.3 | 11.4 kcal |
What stair training can do
Allison and colleagues (2017) trained previously inactive young women with very short stair workouts three times a week for six weeks. Three 20-second all-out climbs per session raised peak aerobic fitness by about 12%. A second version, three 60-second bouts of climbing up and down one flight, raised it by about 7%. These were small studies of about a dozen people each, but they show that brief stair climbing is real exercise.
Stairs are vigorous for many people. Start with one or two flights at a comfortable pace, use the handrail, and rest on landings. If you have a heart, lung or joint condition, or get chest pain, dizziness or unusual breathlessness on stairs, talk to your doctor.