Roof Pitch in Degrees: Chart and Converter

Switch between the x/12 pitch roofers use and the angle a saw, phone app or solar installer wants. 4/12, 4:12, "4 in 12" and "4 on 12" all mean the same pitch: 4 inches of rise per 12 inches of run.

Pitch to degrees

Degrees to pitch

Common roof pitches in degrees

Quick answers: the most-searched pitches in degrees
Pitch	Also written	Degrees	Slope %
1/12	1:12, 1 in 12	4.76°	8.3%
2/12	2:12, 2 in 12	9.46°	16.7%
3/12	3:12, 3 in 12	14.04°	25.0%
4/12	4:12, 4 in 12	18.43°	33.3%
5/12	5:12, 5 in 12	22.62°	41.7%
6/12	6:12, 6 in 12	26.57°	50.0%
7/12	7:12, 7 in 12	30.26°	58.3%
8/12	8:12, 8 in 12	33.69°	66.7%
9/12	9:12, 9 in 12	36.87°	75.0%
10/12	10:12, 10 in 12	39.81°	83.3%
12/12	12:12, 12 in 12	45.00°	100.0%

What is 1:12 in degrees?

1:12 is 4.76 degrees (arctan(1 ÷ 12)), an 8.33% slope. On a roof, 1/12 is a low-slope pitch that needs a membrane or low-slope metal, not shingles. The same 1:12 ratio is the maximum slope the ADA allows for a wheelchair ramp, which is why "1:12 in degrees" comes up so often: 1 inch of rise for every 12 inches of length, 4.76°.

Half pitches in degrees (0.5/12 to 11.5/12)

Roof pitch in degrees for half-inch pitches
Pitch	Degrees	Pitch	Degrees
0.5/12	2.39°	6.5/12	28.44°
1.5/12	7.13°	7.5/12	32.01°
2.5/12	11.77°	8.5/12	35.31°
3.5/12	16.26°	9.5/12	38.37°
4.5/12	20.56°	10.5/12	41.19°
5.5/12	24.62°	11.5/12	43.78°

Degrees to roof pitch chart

Angle in degrees to x/12 roof pitch
Angle	Pitch (rise per 12)	Nearest whole pitch	Slope %
5°	1.05/12	1/12	8.7%
10°	2.12/12	2/12	17.6%
14°	2.99/12	3/12	24.9%
15°	3.22/12	3/12	26.8%
18°	3.90/12	4/12	32.5%
20°	4.37/12	4/12	36.4%
22.5°	4.97/12	5/12	41.4%
25°	5.60/12	6/12	46.6%
27°	6.11/12	6/12	51.0%
30°	6.93/12	7/12	57.7%
33°	7.79/12	8/12	64.9%
35°	8.40/12	8/12	70.0%
40°	10.07/12	10/12	83.9%
45°	12.00/12	12/12	100.0%
50°	14.30/12	14/12	119.2%
60°	20.78/12	21/12	173.2%

A 25 degree roof is a 5.60/12 pitch, so about 5.5/12 to 5.6/12. A 30 degree roof is 6.93/12, close to 7/12.

Slope percent to degrees

Percent slope is rise ÷ run × 100, so a 12% slope rises 12 ft per 100 ft. Degrees = arctan(percent ÷ 100). 12% is 6.84° (a 1.44/12 pitch), 25% is 14.04° (3/12), 50% is 26.57° (6/12) and 100% is 45° (12/12).

The conversion

Degrees = arctan(rise ÷ 12) e.g. arctan(7 ÷ 12) = 30.26° Pitch = 12 × tan(degrees) e.g. 12 × tan(22.5°) = 4.97 → about 5/12

Your calculator needs to be in degree mode for the tan and arctan keys. On a spreadsheet, use =DEGREES(ATAN(B2/12)) and =12*TAN(RADIANS(C2)).

Full pitch to degrees chart

Roof pitch to degrees, 1/12 to 24/12
Pitch	Angle	Multiplier	Slope %	Hip/valley factor
1/12	4.76°	1.0035	8.3%	1.4167
2/12	9.46°	1.0138	16.7%	1.4240
3/12	14.04°	1.0308	25.0%	1.4361
4/12	18.43°	1.0541	33.3%	1.4530
5/12	22.62°	1.0833	41.7%	1.4743
6/12	26.57°	1.1180	50.0%	1.5000
7/12	30.26°	1.1577	58.3%	1.5298
8/12	33.69°	1.2019	66.7%	1.5635
9/12	36.87°	1.2500	75.0%	1.6008
10/12	39.81°	1.3017	83.3%	1.6415
11/12	42.51°	1.3566	91.7%	1.6853
12/12	45.00°	1.4142	100.0%	1.7321
13/12	47.29°	1.4743	108.3%	1.7815
14/12	49.40°	1.5366	116.7%	1.8333
15/12	51.34°	1.6008	125.0%	1.8875
16/12	53.13°	1.6667	133.3%	1.9437
17/12	54.78°	1.7341	141.7%	2.0017
18/12	56.31°	1.8028	150.0%	2.0616
19/12	57.72°	1.8727	158.3%	2.1230
20/12	59.04°	1.9437	166.7%	2.1858
21/12	60.26°	2.0156	175.0%	2.2500
22/12	61.39°	2.0883	183.3%	2.3154
23/12	62.45°	2.1619	191.7%	2.3819
24/12	63.43°	2.2361	200.0%	2.4495

Handy reference points

12/12 = 45°. Rise equals run. Anything steeper is more than 45°.
About 7/12 ≈ 30° (exactly 30.26°). A true 30° roof is 6.93/12.
About 3.2/12 ≈ 15°, and 2/12 ≈ 9.5°. Low-slope products start to matter around here.
Degrees do not scale evenly with pitch: going from 1/12 to 2/12 adds 4.7°, while going from 23/12 to 24/12 adds about 1°.

Worked examples

Solar layout. A racking spec asks for the roof angle. The roof is 5/12: arctan(5 ÷ 12) = 22.62°.

Miter saw. To cut a rafter plumb cut on a 9/12 roof, set the saw to the roof angle, arctan(9 ÷ 12) = 36.87°.

Inclinometer reading. An app reads 18.4° on the shingles. 12 × tan(18.4°) = 3.99, so the roof is 4/12.

Frequently asked questions

What is 1:12 in degrees?

A 1:12 slope (1/12 pitch) is 4.76 degrees, or an 8.33% grade. It is also the steepest slope the ADA allows for a ramp.

How many degrees is a 2/12 pitch?

A 2/12 pitch is 9.46 degrees.

How many degrees is a 3/12 roof pitch?

A 3/12 pitch is 14.04 degrees.

How many degrees is a 4/12 roof pitch?

A 4/12 pitch is 18.43 degrees.

How many degrees is a 5/12 pitch?

A 5/12 pitch is 22.62 degrees.

How many degrees is a 6/12 pitch?

A 6/12 pitch is 26.57 degrees.

How many degrees is an 8/12 pitch?

An 8/12 pitch is 33.69 degrees.

What pitch is a 25 degree roof?

A 25-degree roof is about a 5.6/12 pitch (12 × tan 25° = 5.60).

How many degrees is a 7/12 roof pitch?

A 7/12 pitch is 30.26 degrees, which is why 7/12 is often described as a 30-degree roof.

What pitch is a 45 degree roof?

A 45-degree roof is a 12/12 pitch: it rises 12 inches for every 12 inches of run.

How do I convert degrees to roof pitch?

Multiply the tangent of the angle by 12. For 35 degrees, 12 × tan(35°) = 8.4, so the pitch is about 8.4/12.

Last reviewed 2026-10-21. Results are estimates for planning; confirm quantities with your supplier and requirements with your local building code and the manufacturer's instructions.