Roof Pitch to Degrees • Degrees to Roof Pitch

Slope Conversion Charts • Slope Conversion Formulas

By Jack Gray, Roof Online Editor • Updated October 13, 2022

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Table of Contents

Why Convert Roof Pitch to Degrees or Vice Versa?

There are a few reasons why you’d want to convert roof pitch to degrees or convert a roof slope in degrees to standard roof pitch. But the main issue that comes to mind is the fact that technical literature relating to specific roofing products or roof design more generally often use one or the other, but not both.

This is definitely a problem for English-speaking people outside of the United States reading American roofing literature, and vice versa. Say you’re used to standard roof pitch, you’re checking out a new roofing product on a foreign company’s website, and you read that the product has a minimum slope requirement of 20°. It can slow you down.

A good roof pitch to degrees chart would be a nice to have. Being able to quickly convert standard roof pitch to degrees comes in handy in those situations, and that’s the main reason we put these tables together.

Note: Correct Format When Stating Roof Pitch

When discussing roof pitch, the proper way to state a specific pitch is in the form “X-in-12”, so if you’re talking about a roof that rises 6 units for every 12 units it runs horizontally, you would say that the roof has a 6 in 12 pitch.

In roofing industry literature, the standard abbreviation used for indicating a particular roof pitch has a colon and takes the form “X:12” or “X : 12”, so for a 6 in 12 pitch, you would write “6:12 pitch”.

As a practical matter, an overwhelming number of people looking for information about roof pitch on the internet search for a roof pitch using a slash, as in “6/12”. In order to help more people find what they’re looking for, we are using the “X/12” form in our first table below.

Useful Roof Slope Tools

If you’re not sure what the slope of your roof is and you want to determine that in either degrees or standard roof pitch, we recommend this slope finder on Amazon. It’s very inexpensive and very accurate.

If you want to know the slope of anything to an amazing degree of accuracy and you like cool new tools, you should check out this digital level.

It may be way too expensive for what you need, but this is what professionals use. It will tell you the slope of your roof in degrees, rise/run, or percentage, and automatically convert from one to the other. In other words, it will do everything this article explains how to do.

If you’re using this table, you may want to look into getting yourself a construction calculator. This one is very good.

How to Convert Standard Roof Pitch to Degrees

About This Roof Pitch to Degrees Conversion Table

The following table shows the degree equivalents for all roof slopes in standard pitch from ⅛-in-12 to 36½-in-12.

To see the percentage equivalents for standard rise-in-run roof pitches, see our page Three Ways of Expressing Roof Slope.

That page also explains the math that allows you to convert any roof slope expressed in any way to any other way. Pitch to degrees, percentage to degrees, degrees to percentage, etc. This will help you find the conversion equivalent for any slope not listed.

Conversion Formula for Standard Roof Pitch to Degrees

This is how you convert a slope expressed in standard roof pitch (even a slope that include a fraction) to degrees:

  1. To convert a roof slope expressed as “X-in-12″ to a roof slope expressed in degrees, find the arctangent of (rise/run).
  2. Divide the rise (that’s the “X”, your “X” will vary according to how steep the roof is) by the run (the run is always 12).
  3. Using a scientific calculator, find the arctangent of the result.

There’s a good calculator here at web2.0calc.com. Click the “2nd” button (top left of the calculator field). The “atan” (arctangent) button is the second from the bottom on the left side of the calculator field.

First enter the number you got from dividing your rise by your run (0.791667 in the following example).

Then click the “atan” button, and then the “=” button. This will give you the arctangent of (rise/run).

Example:

  1. For a slope of 9½-in-12
  2. Convert to a decimal: 9½ becomes 9.5
  3. Divide 9.5 by 12 (rise/run is 9.5/12) to get 0.791667
  4. Find the arctangent of 0.791667
  5. Arctan(0.791667) = 38.367497125297
  6. Round this to a reasonable number of digits. Let’s call it 38.37.
  7. A 9½-in-12 roof slope is the same as a 38.37 degree slope.

Table 1: Standard Roof Pitch to Degrees Conversion

Roof Pitch to Degrees Conversion
Standard Roof Pitch
(Roof Slope as X in 12)
Roof Angle
(In Degrees)
0.125 in 12
(⅛ in 12)
0.60°
0.25 in 12
(¼ in 12)
1.19°
0.5 in 12
(½ in 12)
2.39°
1/12 4.76°
1.5/12 7.13°
2/12 9.46°
2.5/12 11.77°
3/12 14.04°
3.5/12 16.26°
4/12 18.43°
4.5/12 20.56°
5/12 22.62°
5.5/12 24.62°
6/12 26.57°
6.5/12 28.44°
7/12 30.26°
7.5/12 32.01°
8/12 33.69°
8.5/12 35.31°
9/12 36.87°
9.5/12 38.37°
10/12 39.81°
10.5/12 41.19°
11/12 42.51°
11.5/12 43.78°
Roof Pitch to Degrees Conversion
Standard Roof Pitch
(Roof Slope as X in 12)
Roof Angle
(In Degrees)
12/12 45°
12.5/12 46.17°
13/12 47.29°
13.5/12 48.37°
14/12 49.4°
14.5/12 50.39°
15/12 51.34°
15.5/12 52.25°
16/12 53.13°
16.5/12 53.97°
17/12 54.78°
17.5/12 55.56°
18/12 56.31°
18.5/12 57.03°
19/12 57.72°
19.5/12 58.39°
20/12 59.04°
20.5/12 59.66°
21/12 60.26°
21.5/12 60.83°
22/12 61.39°
22.5/12 61.93°
23/12 62.45°
23.5/12 62.95°
24/12 63.43°
Roof Pitch to Degrees Conversion
Standard Roof Pitch
(Roof Slope as X in 12)
Roof Angle
(In Degrees)
24.5/12 63.90°
25/12 64.36°
25.5/12 64.80°
26/12 65.22°
26.5/12 65.64°
27/12 66.04°
27.5/12 66.43°
28/12 66.80°
28.5/12 67.17°
29/12 67.52°
29.5/12 67.86°
30/12 68.20°
30.5/12 68.52°
31/12 68.84°
31.5/12 69.15°
32/12 69.44°
32.5/12 69.73°
33/12 70.02°
33.5/12 70.29°
34/12 70.56°
34.5/12 70.82°
35/12 71.08°
35.5/12 71.32°
36/12 71.57°
36.5/12 71.80°

How to Convert Roof Angle in Degrees to Standard Roof Pitch

About This Degrees to Roof Pitch Conversion Table

The following table shows the roof pitch (rise-in-run) equivalents for all roof slopes in degrees from 1° to 72°. Other than the 45° roof slope, which is 12-in-12, none of the standard roof pitches (5-in-12, 6-in-12, etc.) are equal to a whole degree.

To see what the degree or percentage equivalents are for standard rise-in-run roof pitches, see our page Three Ways of Expressing Roof Slope. That page also explains the math that allows you to do the conversions yourself for any slope not listed.

Conversion Formula for Degrees to Standard Roof Pitch

This is how you convert a slope expressed in degrees (even a slope that include a fraction of a degree) to standard roof pitch:

  1. Find the tangent of the degree value.
  2. Multiply the tangent by the run (which is by convention always 12).
  3. That gives you the rise. Put them together as Rise-in-Run.

You can find a good calculator here at web2.0calc.com.

Example:

For a slope of 35.5°:

  • tan(35.5) = 0.713
  • 0.713 x 12 = 8.556
  • giving you a slope of 8.556-in-12 or approximately 8-9/16 in 12.

Table 2: Slopes in Degrees Converted to Standard Roof Pitch

If you’re not sure what the slope of your roof is and you want to determine that in either degrees or rise-in-run, we recommend this slope finder on Amazon. It’s very inexpensive and very accurate.

If you’re using this table, you may want to look into getting yourself a construction calculator. This one is very good.

Convert Roof Slope
from Degrees

to Standard Roof Pitch
Roof Angle
in Degrees
Roof Slope as
Rise in Run
(X in 12)
0.209 in 12
0.419 in 12
0.629 in 12
0.839 in 12
1.050 in 12
1.261 in 12
1.473 in 12
1.687 in 12
1.901 in 12
10° 2.116 in 12
11° 2.333 in 12
12° 2.551 in 12
13° 2.770 in 12
14° 2.991 in 12
15° 3.215 in 12
16° 3.441 in 12
17° 3.669 in 12
18° 3.899 in 12
19° 4.132 in 12
20° 4.368 in 12
21° 4.606 in 12
22° 4.848 in 12
23° 5.094 in 12
24° 5.343 in 12
Convert Roof Slope
from Degrees

to Standard Roof Pitch
Roof Angle
in Degrees
Roof Slope as
Rise in Run
(X in 12)
25° 5.596 in 12
26° 5.853 in 12
27° 6.114 in 12
28° 6.381 in 12
29° 6.652 in 12
30° 6.928 in 12
31° 7.210 in 12
32° 7.498 in 12
33° 7.793 in 12
34° 8.094 in 12
35° 8.403 in 12
36° 8.719 in 12
37° 9.043 in 12
38° 9.375 in 12
39° 9.717 in 12
40° 10.069 in 12
41° 10.431 in 12
42° 10.805 in 12
43° 11.190 in 12
44° 11.588 in 12
45° 12.000 in 12
46° 12.426 in 12
47° 12.868 in 12
48° 13.327 in 12
Convert Roof Slope
from Degrees

to Standard Roof Pitch
Roof Angle
in Degrees
Roof Slope as
Rise in Run
(X in 12)
49° 13.804 in 12
50° 14.301 in 12
51° 14.819 in 12
52° 15.359 in 12
53° 15.925 in 12
54° 16.517 in 12
55° 17.138 in 12
56° 17.791 in 12
57° 18.478 in 12
58° 19.204 in 12
59° 19.971 in 12
60° 20.785 in 12
61° 21.649 in 12
62° 22.569 in 12
63° 23.551 in 12
64° 24.604 in 12
65° 25.734 in 12
66° 26.952 in 12
67° 28.270 in 12
68° 29.701 in 12
69° 31.261 in 12
70° 32.970 in 12
71° 34.851 in 12
72° 36.932 in 12

About the Author

Jack Gray is a principal roof consultant and vice president at the Moriarty Corporation, an award-winning building enclosure consultant firm founded in 1967. He is also the editor of the Roof Online website.

He has worked in the roofing industry for nearly 25 years, with training and practical experience in roof safety, roof inspection, roof condition assessment, estimating, roof design & specification, roof installation, quality assurance, roof maintenance & repair, and roof asset management.

He was awarded the Registered Roof Observer (RRO) professional credential in 2009.

He also served as an infantry paratrooper in the 82nd Airborne Division and attended Cornell University. Read full bio.