Calculate the horizontal length (HL) from a slope in degrees and the slope length (SL). Calculator uses the cosine function "The cosine of an angle in a right angled triangle is the ratio that multiplies the slope length and results in the horizontal length."

Formula: HL = cosine(degrees * π ÷ 180) * SL

Example calculation

slope angle = 18.2°
length of slope line = 14' 11" converted to inches --- 12 * 14 + 11 = 179"

converting the degrees to radians

18.2 * ^π/₁₈₀ = 0.3176499

using the cosine function to get the ratio

cos(0.3176499) = 0.94997

multiplying the slope length by the cosine ratio

179 * 0.94997 = 170" (rounded) = 14' 2" The horizontal distance is 14' 2"

Calculation

1. slope in degrees
2. slope line length
3. number of digits in result

Result

1. the horizontal length