Free Calculator

Roof Pitch Calculator

Enter rise & run — get pitch ratio, angle, slope %, and rafter length instantly

Pitch Calculator

Free · No signup
RISE RUN RAFTER θ 6 : 12 WALL WALL
Common pitches — tap to select
Or enter your own measurements
in
in
ft
in
🏠
Standard Pitch
Most common for residential roofs
Results
Pitch Ratio
6:12
rise per 12" of run
Pitch Angle
26.6°
degrees from horizontal
Slope %
50%
rise ÷ run × 100
Pitch Multiplier
1.118
for material area calc
Rafter Lengths
Line Length
13' 5"
ridge to wall plate
Total w/ Overhang
14' 7"
including eave tail

Pitch Angle Comparison

3:12 14° 4:12 18° COMMON 6:12 27° 9:12 37° 12:12 45° Low slope Standard Steep

Common Pitch Reference Chart

Pitch Angle Slope % Multiplier Type Typical Use
2:129.5°16.7%1.014LowFlat / modern commercial
3:1214.0°25%1.031LowModern homes, sheds
4:1218.4°33.3%1.054StandardMost residential homes
5:1222.6°41.7%1.083StandardResidential, good drainage
6:1226.6°50%1.118StandardMost common, balanced
7:1230.3°58.3%1.158StandardTraditional residential
8:1233.7°66.7%1.202SteepColonial, high snow areas
9:1236.9°75%1.250SteepCape Cod, attic use
10:1239.8°83.3%1.302Very SteepGothic, Victorian
12:1245.0°100%1.414Very SteepA-frame, dramatic designs