Calculate the right stool seat height for any counter, bar, or table, plus the footrest position for your body height and how many stools fit.
Stool Height Formula
The seat height of a stool is set by the height of the surface you sit at, minus the legroom gap you leave for your thighs.
- SH = stool seat height, floor to the top of the seat (in or cm)
- CH = counter, bar, or table height, floor to the top surface (in or cm)
- G = legroom gap, normally 10 to 12 in (25 to 30 cm)
The same relationship rearranges when you already own a stool and want to know what surface it belongs at:
To test a stool and counter you already have, subtract one from the other and compare the result to the 10 to 12 in band:
- C = seat to counter clearance (in or cm)
- C under 8 in is too tight for adult thighs, 10 to 12 in is the target, and over 14 in makes the counter feel too high
Body height sets two more numbers. Knee height, measured from the floor to the back of the knee while seated, is close to a quarter of standing height, and the footrest should sit that same distance below the seat so your legs are supported instead of dangling:
- KH = knee height, floor to the back of the knee (in or cm)
- BH = standing body height without shoes (in or cm)
- FH = footrest height above the floor (in or cm). If FH is zero or less, your feet reach the floor and no footrest is needed
Spacing along a run of counter uses a simple division, where the allowance per stool covers the seat plus elbow room:
- N = number of stools that fit
- L = usable counter length, only the part with an overhang you can sit at (in or cm)
- A = allowance per stool, 24 in for backless, 26 in standard, 28 to 30 in for stools with backs or arms
Each mode of the calculator runs one of these. The seat height mode applies the first formula and names the stool category to shop for. The counter mode reverses it. The fit check returns the clearance and grades it. The body height mode returns your knee height, the seat height that lets your feet rest flat, and the footrest position for standard stools. The spacing mode returns the stool count, the center to center spacing, and the clear gap between seats if you enter a stool width.
Standard Surface, Seat, and Footrest Heights
Stools are sold in four height classes. Match the class to your surface first, then fine tune inside the range.
| Stool class | Surface height | Seat height | Typical use |
|---|---|---|---|
| Chair or dining height | 28 to 30 in (71 to 76 cm) | 17 to 19 in (43 to 48 cm) | Dining tables, desks, breakfast nooks |
| Counter height | 34 to 37 in (86 to 94 cm) | 24 to 27 in (61 to 69 cm) | Kitchen islands and breakfast bars |
| Bar height | 40 to 43 in (102 to 109 cm) | 29 to 32 in (74 to 81 cm) | Home bars, pub tables, raised islands |
| Spectator or extra tall | 44 to 48 in (112 to 122 cm) | 33 to 36 in (84 to 91 cm) | Custom high counters and commercial bars |
The table below is the part most height guides leave out. A stool only feels stable if the footrest lands at your knee height below the seat. Anything lower leaves your legs hanging, and anything higher pushes your knees up and rolls your pelvis back. Compare these numbers to the rail height printed in the product specs before you buy.
| Your height | Knee height | Footrest on a 26 in stool | Footrest on a 30 in stool |
|---|---|---|---|
| 5 ft 0 in (152 cm) | 15.0 in (38 cm) | 11.0 in (28 cm) | 15.0 in (38 cm) |
| 5 ft 4 in (163 cm) | 16.0 in (41 cm) | 10.0 in (25 cm) | 14.0 in (36 cm) |
| 5 ft 8 in (173 cm) | 17.0 in (43 cm) | 9.0 in (23 cm) | 13.0 in (33 cm) |
| 6 ft 0 in (183 cm) | 18.0 in (46 cm) | 8.0 in (20 cm) | 12.0 in (30 cm) |
| 6 ft 4 in (193 cm) | 19.0 in (48 cm) | 7.0 in (18 cm) | 11.0 in (28 cm) |
Most factory bar stools put the rail 11 to 12 in off the floor, which suits users near 6 ft on a 30 in seat. Shorter users get more support from a stool with a wraparound rail or a second lower rung.
Example Problems
Example 1. Seat height and footrest for a kitchen island. Your island measures 36 in from the floor to the top of the stone. Using the standard gap, the seat height is 36 – 11 = 25 in, with a workable range of 24 to 26 in, so you are shopping counter height stools. If you are 5 ft 8 in tall, your knee height is 0.25 x 68 = 17 in, so the footrest should sit 25 – 17 = 8 in above the floor. A stool with a 12 in rail will leave your feet reaching down for it.
Example 2. Checking a stool you already own. You have a 30 in seat height stool and the same 36 in island. The clearance is 36 – 30 = 6 in, which is far below the 10 to 12 in band, so your thighs will hit the counter. Lower the seat by at least 4 in, or move that stool to a surface of 30 + 10 to 30 + 12, which is 40 to 42 in, standard bar height.
FAQ
What size stool do you need for a 36 inch counter? A seat height of 24 to 26 in, which is the counter height class. 25 in is the middle of the range and the safest single choice. Go to the low end if you are under 5 ft 4 in or if the counter has a thick top or an apron under the edge, since both eat into the clearance you actually feel.
How high should a bar stool footrest be? The rail should be one knee height below the seat, which is about a quarter of your standing height. For most adults that is 15 to 19 in below the seat, putting the rail 11 to 15 in above the floor on a 30 in bar stool and 7 to 11 in above the floor on a 26 in counter stool. If the rail is too low your legs dangle and pressure builds under the thighs. If it is too high your knees rise above your hips and your lower back rounds.
Do you measure the stool to the top of the cushion? Yes, and measure it with weight on the seat. A thick foam or leather cushion can compress an inch or more, which turns a snug 9 in clearance into a comfortable 10 in once you sit down. Measure the counter the same way, from the floor to the top surface rather than to a raised edge, and subtract the thickness of any apron or drawer box under the overhang before you judge knee clearance.