Driveway slope calculator: pitch percent, degrees, and drainage
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Searchers looking for a driveway slope calculator or driveway pitch calculator usually want one result: rise and run → grade percent, plus the matching angle in degrees. Keep both measurements in the same unit. That number supports drainage talks and steepness checks before paving starts.
Treat the output as planning geometry — not structural design, ADA certification, or a permit stamp.
Open driveway slope calculator →How slope percent and degrees work
Slope percent = (Rise ÷ Run) × 100
Rise is vertical change; run is horizontal distance. Pair feet with feet, or inches with inches. Illustration: 18 inches of rise across 30 feet of run → 1.5 ft ÷ 30 × 100 = 5%.
Degrees: θ = arctan(rise ÷ run). Near 5% that angle is about 2.9°. Plans may list either unit; the driveway slope calculator reports both so notes line up.
When to use a driveway pitch calculator
- Confirming stormwater moves from garage toward the street rather than into the slab.
- Comparing a proposed regrade against the existing profile before an overlay.
- Giving contractors a measured grade instead of “it feels steep.”
Side-to-side cross-slope also drives sheet flow — take a second rise/run across the width when the drive crowns or tilts.
Tips and caveats
- Prefer horizontal run; measuring along a steep surface inflates run and shrinks percent.
- Long drives often change grade by segment — compute each stretch separately.
- Steep profiles affect scraping, winter traction, and paving difficulty; ask local crews.
- Once length and width are fixed, surface tons belong on the driveway asphalt calculator.
Measuring rise and run in the field
Practical approach: set a straight board or string along the intended run, level it, then measure the gap from the downhill end down to the pavement — that gap is rise for that board length. Sample a few stations; many drives steepen near the curb and flatten at the apron.
Write down percent and degrees when your contractor or city uses different vocabulary. After grade is locked, surface tons come from the asphalt tonnage calculator. Planning geometry only — codes and an engineer set legal maxima and accessible routes.
Related tools
FAQ
How do I calculate driveway slope percent?
Slope % = (rise ÷ run) × 100 using the same length unit for both. A 1 ft rise over 20 ft run is 5%.
What is the difference between slope percent and degrees?
Percent is rise/run × 100. Degrees come from the angle whose tangent is rise/run (atan). Our calculator shows both so you can match plan notes or code language.
Is there one legal maximum slope?
Rules vary by jurisdiction and whether the path is a driveway, sidewalk, or accessible route. Check local code and your engineer or contractor — do not treat a web calculator as a permit document.