Rafter Length Calculator

Calculate common rafter length from span and pitch for framing and material orders.

Distance between supports.
ft
Angle of incline, often as ratio or percentage.
:12
Enter the overhang value for this calculation.
in

Results

Run (Half Span):
Calculated run (half span) based on your inputs.
-ft
Total Rise:
Sum of all calculated values.
-ft
Rafter Length:
Calculated rafter length based on your inputs.
-ft
With Overhang:
Sum of all calculated values.
-ft
Reference: Industry Standards. Standard rafter calculation methods per IRC framing guidelines.