★ CONSTRUCTION · BATHROOM · FIXTURES
FITS — with 42 inches in front. A 60 x 72 in room fits an elongated toilet, which needs 30 x 51 in: 15 in of centreline to each side and 21 in clear in front. Enter your room to find whether your toilet fits — and how much room each type needs.
A toilet needs 15 in from its centreline to each side wall and 21 in clear in front of the bowl. This calculator works out whether your room fits your toilet, the centreline and front clearance, and the shortfall when it does not — with the full standard toilet size table. Reference table #209.
A toilet needs two clearances, and both are code minimums. The first is width: 15 in from the toilet centreline to each side wall, vanity or other fixture, which is 30 in of total width. The second is depth: 21 in clear in front of the bowl, measured from the front of the bowl to the wall, door or fixture opposite. The room a toilet needs is 30 in wide and the toilet length plus 21 in deep. A toilet fits when the room is at least 30 in wide and at least the toilet length plus 21 in deep. Sizes are industry-standard nominal sizes and brands vary by ±1/2 in, so check the label before you buy.
At the defaults — a 60 in wide room, 72 in deep, with an elongated toilet (30 in long) — the room needs 30 in of width and 30 + 21 = 51 in of depth. The room is 60 in wide and 72 in deep, so it FITS. The centreline is 60 ÷ 2 = 30 in to each side wall. The front clearance is 72 − 30 = 42 in. The extra width is 60 − 30 = 30 in, and the extra depth is 72 − 51 = 21 in.
| Type | Rough-in (in) | Length (in) | Width (in) | Seat height (in) | Notes |
|---|---|---|---|---|---|
| Round-front standard | 12 | 28 | 20 | 15 | The classic short bowl; best for small rooms. |
| Elongated standard | 12 | 30 | 20 | 15 | The most common bowl; two inches longer than round. |
| Comfort-height / ADA elongated | 12 | 30 | 20 | 17–19 | Taller seat, easier to sit and stand; same footprint as elongated. |
| Compact / small-space | 10 | 25 | 18 | 15 | Short and narrow; for powder rooms and tight spaces. |
| Wall-hung | 12 (carrier) | 22 | 15 | 17–19 (adjustable) | Bowl hangs off the wall; the tank hides inside the wall. |
| Corner | 12 | 28 | 20 | 15 | Sits across a corner; the tank is triangular. |
| Case | Required (in) | Fits? | Centerline (in) | Front (in) |
|---|---|---|---|---|
| Default (60 x 72 in, elongated) | 30 x 51 | FITS | 30 in | 42 in |
| 36 x 60 in, elongated | 30 x 51 | FITS | 18 in | 30 in |
| 30 x 48 in, elongated | 30 x 51 | DOES NOT FIT | 15 in | 18 in |
| 30 x 48 in, compact | 30 x 46 | FITS | 15 in | 23 in |
| 48 x 60 in, compact | 30 x 46 | FITS | 24 in | 35 in |
| 60 x 72 in, round | 30 x 49 | FITS | 30 in | 44 in |
| 60 x 72 in, wall-hung | 30 x 43 | FITS | 30 in | 50 in |
| 24 x 72 in, elongated | 30 x 51 | DOES NOT FIT | 12 in | 42 in |
| 36 x 40 in, elongated | 30 x 51 | DOES NOT FIT | 18 in | 10 in |
Setup: room width 60 in, room depth 72 in, toilet type elongated (30 in long, 20 in wide).
Line 1 — the required width. 15 in centreline to each side wall = 30 in.
Line 2 — the required depth. 30 in of toilet + 21 in clear in front = 51 in.
Line 3 — does it fit? The room is 60 in wide and 72 in deep, and 60 ≥ 30 and 72 ≥ 51, so it FITS.
Line 4 — the centreline. 60 ÷ 2 = 30 in to each side wall.
Line 5 — the front clearance. 72 − 30 = 42 in.
Line 6 — the extras. Extra width 60 − 30 = 30 in. Extra depth 72 − 51 = 21 in.
Reverse: the minimum room depth is 51 in for an elongated toilet, 49 in for round, 46 in for compact and 43 in for wall-hung; the minimum room width for any type is 30 in (15 in centreline each side).
36 x 60 in room, elongated: the room needs 30 x 51 in, and 36 ≥ 30 and 60 ≥ 51, so it FITS. The centreline is 36 ÷ 2 = 18 in to each side, the front clearance is 60 − 30 = 30 in, the extra width is 6 in and the extra depth is 9 in.
30 x 48 in room, elongated: the room needs 30 x 51 in, and 30 ≥ 30 but 48 is less than 51, so it DOES NOT FIT — depth short by 3 in. The front clearance would be 48 − 30 = 18 in, and it needs 21 in. Three inches is all that is missing.
30 x 48 in room, compact: the same room with a compact toilet needs 30 x 46 in, and 30 ≥ 30 and 48 ≥ 46, so it FITS. The front clearance is 48 − 25 = 23 in, which clears the 21-in minimum by 2 in. Five inches less toilet is the whole difference.
48 x 60 in room, compact: the room needs 30 x 46 in, and 48 ≥ 30 and 60 ≥ 46, so it FITS. The centreline is 48 ÷ 2 = 24 in, the front clearance is 60 − 25 = 35 in, the extra width is 18 in and the extra depth is 14 in.
60 x 72 in room, round: a round toilet is 28 in long, so the room needs 30 x 49 in, and 60 ≥ 30 and 72 ≥ 49, so it FITS. The front clearance is 72 − 28 = 44 in and the extra depth is 23 in. Two inches shorter than elongated, two inches more room in front.
60 x 72 in room, wall-hung: a wall-hung toilet is 22 in long, so the room needs 30 x 43 in, and 60 ≥ 30 and 72 ≥ 43, so it FITS. The front clearance is 72 − 22 = 50 in and the extra depth is 29 in. The shortest bowl leaves the most room in front.
24 x 72 in room, elongated: the room needs 30 x 51 in, and 24 is less than 30, so it DOES NOT FIT — width short by 6 in. The centreline is 24 ÷ 2 = 12 in to each side, and it needs 15 in. The depth is fine at 72 in, but the width is a hard minimum and no toilet type changes it.
36 x 40 in room, elongated: the room needs 30 x 51 in, and 36 ≥ 30 but 40 is less than 51, so it DOES NOT FIT — depth short by 11 in. The front clearance would be 40 − 30 = 10 in, and it needs 21 in. Eleven inches short is too much for a compact toilet to save: a compact needs 46 in of depth, and the room is still 6 in short.
Reverse — the other way round: the minimum room depth is 51 in for an elongated toilet, 49 in for round, 46 in for compact and 43 in for wall-hung; the minimum room width for any type is 30 in.
The model assumes the IRC/NKBA code minimums: 15 in from the toilet centreline to each side wall and 21 in clear in front of the bowl, and the table’s industry-standard nominal sizes. It assumes the room width and depth you enter are measured wall to wall, and that the toilet sits against the back wall — check them, because a room measured to the door frame is not the room the toilet sits in, and a vanity next to the toilet eats the centreline on that side. It leaves out the door swing, which needs its own clearance, and the rough-in, which is a separate measurement from the finished wall to the centre of the drain. Rounding convention: inches are shown to two decimals, the fit is a yes or no, and all figures are computed from unrounded values, rounded only for display.
| Output | Formula | What it means |
|---|---|---|
| Fits? | room width ≥ 30 in AND room depth ≥ toilet length + 21 in | FITS. |
| Required width | 15 in centerline to each side wall | 30 in. |
| Required depth | toilet length + 21 in clear in front of the bowl | 51 in. |
| Centerline to each side wall | room width ÷ 2 | 30 in. |
| Front clearance | room depth − toilet length | 42 in. |
| Extra width | room width − 30 in | 30 in. |
| Extra depth | room depth − (toilet length + 21 in) | 21 in. |
| Shortfall | what is missing when it does not fit | none. |
| Min depth: elongated | 30 + 21 | 51 in. |
| Min depth: round | 28 + 21 | 49 in. |
| Min depth: compact | 25 + 21 | 46 in. |
| Min depth: wall-hung | 22 + 21 | 43 in. |
| Min width: any type | 15 + 15 | 30 in. |
| 36 x 60 in, elongated | same model, 36 x 60 in, elongated | Required 30 x 51 in; FITS. Centerline 18 in, front 30 in, extra width 6 in, extra depth 9 in, shortfall none. |
| 30 x 48 in, elongated | same model, 30 x 48 in, elongated | Required 30 x 51 in; DOES NOT FIT. Centerline 15 in, front 18 in, extra width 0 in, extra depth -3 in, shortfall depth short by 3 in. |
| 30 x 48 in, compact | same model, 30 x 48 in, compact | Required 30 x 46 in; FITS. Centerline 15 in, front 23 in, extra width 0 in, extra depth 2 in, shortfall none. |
| 48 x 60 in, compact | same model, 48 x 60 in, compact | Required 30 x 46 in; FITS. Centerline 24 in, front 35 in, extra width 18 in, extra depth 14 in, shortfall none. |
| 60 x 72 in, round | same model, 60 x 72 in, round | Required 30 x 49 in; FITS. Centerline 30 in, front 44 in, extra width 30 in, extra depth 23 in, shortfall none. |
| 60 x 72 in, wall-hung | same model, 60 x 72 in, wall-hung | Required 30 x 43 in; FITS. Centerline 30 in, front 50 in, extra width 30 in, extra depth 29 in, shortfall none. |
| 24 x 72 in, elongated | same model, 24 x 72 in, elongated | Required 30 x 51 in; DOES NOT FIT. Centerline 12 in, front 42 in, extra width -6 in, extra depth 21 in, shortfall width short by 6 in. |
| 36 x 40 in, elongated | same model, 36 x 40 in, elongated | Required 30 x 51 in; DOES NOT FIT. Centerline 18 in, front 10 in, extra width 6 in, extra depth -11 in, shortfall depth short by 11 in. |
The math is exact for the numbers you enter: the room needs 30 in of width and the toilet length plus 21 in of depth, and it fits when the room is at least that big in both directions. What the model cannot do is measure your room: check the width and depth, because a vanity next to the toilet eats the centreline on that side, and a door that swings into the room eats the front clearance. It assumes the toilet sits against the back wall and leaves out the door swing and the rough-in, which is measured from the finished wall to the centre of the drain. Sizes are industry-standard nominal sizes and brands vary by ±1/2 in — check the label. For the cabinets next to the toilet, see cabinet size chart; for the deck outside, see deck board size chart.
Bright Side Kit. "Toilet Size Chart: Standard Dimensions & Clearances 2026." https://brightoolbox.com/toilet-size-chart/ Accessed October 25, 2026.12 inches, measured from the finished wall to the centre of the drain. Most toilets are made for a 12-in rough-in, and the standard round and elongated bowls in the table above are all 12-in. A 10-in rough-in applies when the wall is closer to the drain — that is what the compact toilet is for — and a 14-in rough-in applies in some older homes, where the drain sits further out. Measure the rough-in before you buy: a 12-in toilet on a 10-in rough-in will not fit, and a 12-in toilet on a 14-in rough-in leaves a 2-in gap behind the tank.
15 inches from the centre of the toilet to the wall on each side. The code minimum is 15 in from the toilet centreline to each side wall, vanity or other fixture, which is 30 in of total width. At the defaults the room is 60 in wide, so the centreline is 30 in to each side — twice the minimum. A 30-in wide room is exactly at the minimum, with 15 in to each side, and it fits. A 24-in wide room has only 12 in to each side, so it does not fit: it is 6 in short.
21 inches clear in front of the bowl. The code minimum is 21 in of clear space in front of the toilet bowl, measured from the front of the bowl to the wall, door or fixture opposite. An elongated toilet is 30 in long, so the room needs 30 + 21 = 51 in of depth. At the defaults the room is 72 in deep, so the front clearance is 42 in. A 48-in deep room with an elongated toilet leaves only 18 in in front, which is 3 in short — a compact toilet at 25 in long needs only 46 in of depth, so it fits the same room with 23 in in front.
No — the same footprint, just a taller seat. A comfort-height or ADA toilet is 17–19 in tall at the seat, against 15 in for a standard toilet, but it is the same 30 in long and 20 in wide as a standard elongated toilet. It needs the same 30 in of width and 51 in of depth, with the same 15-in centreline and 21-in front clearance. The extra height is in the bowl, not in the floor space, so a room that fits an elongated toilet fits a comfort-height one too.
30 inches wide and 51 inches deep for an elongated bowl. That is 15 in of centreline to each side wall and 21 in clear in front of a 30-in bowl. A round bowl needs 30 in wide and 49 in deep, a compact needs 30 in wide and 46 in deep, and a wall-hung needs 30 in wide and 43 in deep. The width never changes: every type needs 30 in, because the centreline rule is the same for all of them.
Go compact, or go wall-hung. A 30 x 48 in room does not fit an elongated toilet — it is 3 in short on depth — but it fits a compact toilet, which needs only 46 in of depth and leaves 23 in in front. A wall-hung toilet needs only 43 in of depth, so it fits rooms an elongated toilet cannot. If the room is under 30 in wide, no standard toilet fits: the centreline rule is a hard minimum, and the only fix is a wider room.