5 percent: a 1 in 20 slope
5% is 2.86°, 1 unit up for every 20 along. It is the gentle end of the 5 to 10% that most driveways sit in, and it falls 0.6 inches per foot, more than twice what drainage needs.
As a ramp it is easier than the 1:12 limit: to rise 24 inches it needs 40 feet of run, where a 1:12 ramp needs 24 feet.
A 40 foot driveway at 5% climbs 2 feet from the street to the garage.
5% slope: rise over a distance
A 5% slope rises 5 feet in every 100 feet of level distance.
| Run (level distance) | Rise in inches | Rise in feet | Length along the slope |
|---|---|---|---|
| 1 ft | 0.6 in | 0.05 ft | 1.00 ft |
| 10 ft | 6 in | 0.5 ft | 10.01 ft |
| 20 ft | 12 in | 1 ft | 20.02 ft |
| 50 ft | 30 in | 2.5 ft | 50.06 ft |
| 100 ft | 60 in | 5 ft | 100.12 ft |
Worked example
5 ÷ 100 = 0.05. The angle is the arctangent of that: arctan(0.05) = 2.86°. As a ratio, 100 ÷ 5 = 20, so the slope is 1 in 20. Per foot, 0.05 × 12 = 0.6 inches.
Nearby grades in degrees
| Grade | Angle | Ratio | Rise per foot |
|---|---|---|---|
| 1% | 0.57° | 1 in 100 | 0.12 in |
| 2% | 1.15° | 1 in 50 | 0.24 in |
| 5% | 2.86° | 1 in 20 | 0.6 in |
| 8.33% | 4.76° | 1 in 12 | 1 in |
| 10% | 5.71° | 1 in 10 | 1.2 in |
| 12% | 6.84° | 1 in 8.33 | 1.44 in |
For any other rise, run or grade use the slope and grade calculator. The guide slope and grade for drainage and ramps covers how much fall each job needs.
Want to change anything else? The calculator above is the full Slope and Grade Calculator: edit any number and the results update instantly.
Tools & materials for this project
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Frequently asked questions
What is a 5 percent slope in degrees?
2.86 degrees. Divide the percent by 100 and take the arctangent: arctan(0.05) = 2.86°.
Is a 5 percent slope steep?
No. It is 2.86°, the gentle end of the usual driveway range and gentler than the 1:12 (8.33%) ramp limit, though it is more than twice the 2% that drainage needs.
How much does a 5% slope rise per foot?
0.6 inches for every foot of run, which is 6 inches over 10 feet and 5 feet over 100 feet.
Related sizes and guides
Estimates only. Results assume standard materials and simple shapes. Supplier products vary, and the final call on quantity, structure and safety is yours. Check your local code and your supplier's guidance before ordering.