One flight of stairs, meaning one floor of a building, is about 16 steps. Apple treats a floor as roughly 3 meters (just under 10 feet) of climbing, and US building codes cap each step at 7¾ inches in homes and 7 inches in commercial buildings, so a floor that high takes at least 16 or 17 steps. That makes 28 floors about 450 stair steps and 100 flights about 1,600. In effort, a steady climb is worth about 4 walking steps for every stair, or about 60 walking steps per flight: 28 flights comes to about 1,720 walking steps and 100 flights about 6,150.

How many steps are in one flight of stairs?

The number of steps is the height you climb divided by the height of each step, called the riser. Building codes set the tallest riser allowed:

Because steps can't be taller than that, a floor needs at least this many:

Height between floorsHomes (risers up to 7¾ in)Commercial (risers up to 7 in)
8 ft 6 in (2.6 m)1415
9 ft (2.7 m)1416
3 m (9 ft 10 in), Apple's floor1617
10 ft (3.05 m)1618
12 ft (3.7 m)1921

Minimum steps = height ÷ maximum riser, rounded up. Stairs with shorter risers have more steps, and local codes can differ.

Stairwells used in research land in the same range. One public stairway, climbed by 103 people in a study, had 180 steps over 11 stories, about 16 per story (Teh & Aziz, 2002 (opens in a new tab)). Another had 86 steps over 5 floors, about 17 per floor (Halsey et al., 2012 (opens in a new tab)).

That second stairwell also shows why "flight" can mean two things: its 5 floors were split into 8 flights. To builders, a flight is a run of steps between landings, and the IRC limits one flight to 12 feet 7 inches of rise (Section R311.7.3, quoted from Washington State's adopted code (opens in a new tab)). So a floor can have two flights. Your iPhone counts by height instead.

To count your own stairs, count the risers, not the treads. A flight with 16 risers has 15 treads; the 16th step puts you on the floor above.

What counts as a "flight climbed" on iPhone and Apple Watch?

Apple's developer documentation for Health's Flights Climbed data says only that it "measures the number flights of stairs that the user has climbed," and that iPhone and Apple Watch can collect it automatically (HealthKit: flightsClimbed (opens in a new tab)). It doesn't say how tall a flight is.

Its documentation for the pedometer data that iPhone and Apple Watch record is more specific (Core Motion: floorsAscended (opens in a new tab)):

  • A floor is about 3 meters. "A single floor has a height of approximately three meters."
  • Only climbing on foot counts. It reflects floors climbed "while the user was walking or running up stairs," not by elevator "or other assisted means."
  • Not every device counts floors. Apps must check that floor counting is available (CMPedometer (opens in a new tab)).

Apple doesn't say whether Health's Flights Climbed follows exactly the same rule, but this is the closest it comes to a definition. By that definition, a flight is a height, not a number of stairs.

If you carry an iPhone and wear an Apple Watch, both can record flights. When several sources record the same data, Health gives priority to the source at the top of its data source list, which you can reorder (Apple Support (opens in a new tab)).

Does your iPhone count each stair as a step?

Apple doesn't document how it counts steps on stairs. Its documentation does show that the pedometer treats climbing as walking: floors count only while you walk or run up stairs, and the same pedometer data reports steps alongside floors. We couldn't find a published study that checked iPhone step counts on stairs, so we can't say how closely each stair matches one counted step.

Two points hold either way:

  • Taking stairs two at a time halves your footsteps. A 16-stair flight becomes 8 steps.
  • One at a time costs more energy in total. In a study of 14 people, two at a time burned energy faster (9.2 vs 8.5 kcal a minute), but one at a time was "energetically more expensive in total over the entirety of a stairway" (Halsey et al., 2012 (opens in a new tab)).

How many steps is 28 floors? Floors to steps, 1 to 100 flights

This table converts flights to stair steps, at 16 per flight, and to walking-step equivalents: the walking steps that would burn the same active calories as a steady climb.

FlightsStair stepsHeightTime, steady paceWalking-step equivalent
1163 m (10 ft)11 secondsabout 60
58015 m (49 ft)53 secondsabout 310
1016030 m (98 ft)1¾ minutesabout 620
2032060 m (197 ft)3½ minutesabout 1,230
2844884 m (276 ft)5 minutesabout 1,720
50800150 m (492 ft)9 minutesabout 3,080
1001,600300 m (984 ft)18 minutesabout 6,150

Height at Apple's roughly 3 m per floor. Time and walking steps assume about 90 stairs a minute at the 2011 Compendium's fast stair-climbing value (8.8 METs), against walking at 3 mph for a 5'9" walker, rounded to the nearest 10.

The walking-step column uses the same model as our activity to steps converter. Sixteen stairs at about 90 a minute, the pace people chose in the Halsey study (86 stairs in 57.3 seconds), take about 11 seconds. Climbing fast is 8.8 METs and walking at 3 mph is 3.5 METs (Compendium codes 17134 and 17190), so counting only energy above rest, a minute of climbing equals (8.8 − 1) ÷ (3.5 − 1) = 3.12 minutes of walking. At our model's 111 steps a minute, 11 seconds of climbing is worth about 62 walking steps.

Body weight cancels out, because it scales both activities equally. Taller walkers take slightly fewer steps per minute, so their equivalents run a little lower.

Note

Rule of thumb: at a steady pace, one stair is worth about 4 walking steps, and one flight about 60. Equivalent steps compare effort. They aren't extra steps your phone records.

For a stair machine, use our stairs to steps converter. It uses the Compendium's stair-machine value of 9.0 METs, which puts 25 minutes at about 8,872 walking steps.

Is climbing stairs harder than walking?

Per minute, a brisk climb burns about three times the active calories of a moderate walk, while a slow climb burns only a little more. These values come from the 2011 Compendium of Physical Activities (opens in a new tab):

Activity (Compendium code)METWalking minutes per minuteWalking steps per minute
Walking, 3 mph, level (17190)3.51.0about 111
Walking down stairs (17070)3.51.0about 111
Climbing stairs, slow (17133)4.01.2about 133
Climbing stairs, fast (17134)8.83.1about 346
Stair machine (02065)9.03.2about 355

Equivalents: (MET − 1) ÷ (3.5 − 1) × 110.9 steps a minute. See our MET values chart for walking speeds and terrain.

Measured climbs fit this picture. In the study of 103 people climbing 11 stories, going up averaged 9.6 METs and coming down 4.9 METs, about 0.11 kcal per step up and 0.05 kcal per step down (Teh & Aziz, 2002 (opens in a new tab)).

The US Physical Activity Guidelines class 6.0 METs or more as vigorous and 3.0 to under 6.0 as moderate (Physical Activity Guidelines for Americans (opens in a new tab)). So a brisk climb is vigorous exercise, and a slow one is moderate, like brisk walking.

How to use stairs to add to your day

The same guidelines say bouts of any length count: "Even a brief episode of physical activity like climbing up a few flights of stairs counts." They advise adults to get 150 to 300 minutes of moderate activity a week, or 75 to 150 minutes of vigorous activity, or a mix.

  • Take a few flights instead of the elevator on the way up, and ride down if you prefer.
  • Try stair "snacks." In a small randomized trial, sedentary young adults who briskly climbed three flights (60 steps) three times a day, three days a week, for six weeks ended with higher peak oxygen uptake, a measure of aerobic fitness. The authors called the gain modest (Jenkins et al., 2019 (opens in a new tab)).
  • Break up long sitting with a flight or two between meetings.

Going down is harder on your knees. In a study that measured forces through instrumented knee replacements, peak knee load averaged 346% of body weight going down stairs, 316% going up and 261% in level walking (Kutzner et al., 2010 (opens in a new tab)). If stairs bother your knees, walking up and riding down is a reasonable compromise. Our guide to walking with bad knees covers building up by symptoms.

Make the stairs safe. The CDC's home fall-prevention checklist recommends handrails on both sides along the full length of the stairs, a light and switch at the top and bottom, and keeping objects off the steps (CDC (opens in a new tab)). Stop and get medical advice if climbing brings on chest pain, unusual breathlessness, dizziness or sharp joint pain, and if you have a heart or lung condition, ask your doctor how hard to push. For a gentle start, see stair climbing benefits.

If you'd like to see flights next to your steps, Stepsly, our iPhone app, shows floors climbed alongside steps, distance and active calories, read from Apple Health. It's iPhone-only with no Apple Watch app, free to download, and requires Stepsly Pro.

Questions people ask

How many steps is 10 flights of stairs?

About 160 stair steps, climbing about 30 meters (98 feet). At a steady pace that takes under two minutes and is worth about 620 walking steps in active calories.

How many flights of stairs equal 10,000 steps?

By energy, about 163 flights at a steady pace: roughly 2,600 stair steps and 29 minutes of climbing. Getting back down adds as many stairs again, and descending loads your knees most.

How many calories does a flight of stairs burn?

About 1.6 active calories per flight for a 70 kg (154 lb) person climbing steadily, and about 2.1 at 90 kg (198 lb), from (8.8 − 1) × weight in kg × hours. That's about 45 active calories for 28 flights and 160 for 100 flights at 70 kg. Pace and fitness change these estimates.

Does walking down stairs count?

For energy, walking down stairs is 3.5 METs in the Compendium, the same as walking at 3 mph, so a minute going down is worth about a minute of walking. It doesn't add to your climb: Health's metric is flights climbed, and Apple's pedometer tracks floors descended separately.

Is a flight of stairs the same as a floor?

Not always. Builders call each run of steps between landings a flight, so one floor can have two. Your iPhone works by height: Apple's pedometer documentation puts a floor at about 3 meters, however many stairs that takes.

Sources, notes & disclaimers