Construction

Grade & Construction Slope Calculators

Percent, ratio, degrees and inches per foot — the four ways slope gets written on a jobsite. Enter feet, inches or metric; each tool checks your figure against the limit that applies to that trade.

Start here Percent Grade Calculator

Convert rise and run into percent grade, ratio and degrees — in feet, inches or metric.

Open calculator →Roof Pitch Calculator

Rise-in-12 pitch, angle, percent and the rafter multiplier for framing.

Open calculator →Ramp Slope Calculator

Check a wheelchair ramp against the ADA 1:12 limit and get the run and landings you need.

Open calculator →Pipe Slope Calculator

Drainage fall per foot, percent and ratio — checked against the 1/4 in/ft minimum.

Open calculator →

Overview of Construction Slope Tools

Grade & Construction Slope Tools serves as a specialized calculation hub engineered to solve slope, incline, and elevation changes across diverse building trades. While every construction discipline relies on the fundamental relationship between vertical elevation and horizontal distance, each field utilizes distinct units and compliance standards. This centralized suite eliminates manual conversions by standardizing slope output into percentages, pitch ratios, linear fall rates, and angular degrees.

Fundamentals of Construction Slope Mathematics

All slope calculations stem from the core geometric principle of rise over run, expressed as m = rise/run. In practical field applications, this basic ratio is converted into specific industry formats:

  • Percent Grade: Calculated as (rise/run) × 100, expressing inclination as a horizontal percentage.
  • Pitch Ratio: Written as x:12 or 1:x, comparing vertical change against a fixed base distance.
  • Angular Degrees: Derived using the arctangent function θ = arctan(rise/run), yielding exact angular tilt.
  • Linear Fall Rate: Expressed as inches of drop per foot of horizontal run for continuous drainage.

How to Choose the Right Calculator

While every trade relies on the same rise-over-run geometric baseline, field requirements demand specialized units, compliance thresholds, and measurement formats. Selecting the appropriate tool ensures fast input and accurate results for your specific workflow:

  • Grade / Percent: Serves as the general converter for roads, driveways, and landscaping slopes, instantly translating elevation changes into percent grade, pitch ratio, or angular degrees.
  • Pipe Slope: Designed for plumbing and drainage systems, evaluating linear fall in inches per foot to verify minimum flow velocity standards such as 1/4" per foot.   
  • Roof Pitch: Tailored for framers and roofers to calculate x:12 pitch ratios, roof slope angles, and exact rafter length multipliers.   
  • Ramp / ADA Slope: Formatted specifically for accessibility compliance, evaluating ramp runs against strict maximum slope limits like the 1:12 ADA standard.

By accurately converting between percentages, pitch ratios, and angular degrees, these specialized calculators simplify slope measurement for any construction project. Whether you are setting up drainage lines, framing a roof, or verifying ADA compliance, choosing the right trade tool ensures total accuracy and saves valuable time on site. Select a calculator above to start your project calculations right here!

These results are estimates for study and planning. Building codes, ADA requirements and local drainage rules vary — confirm any construction figure with your local building department, the current code edition and a licensed professional before you build.
More slope calculators
Slope CalculatorSlope from two points, a line equation, or a point plus slope — with equation, angle, intercepts, distance and a graph.Slope Formula CalculatorApply m = (y2 - y1) / (x2 - x1) to two points with every substitution shown.Slope Intercept Form CalculatorBuild y = mx + b from a slope and intercept or from two points, and graph it.Point Slope Form CalculatorTurn one point and a slope into y - y1 = m(x - x1), plus slope-intercept and standard form.X and Y Intercept CalculatorFind where a line crosses both axes, from two points or from an equation.Midpoint CalculatorThe exact halfway point between two coordinates, plotted on a graph.Distance Between Two Points CalculatorStraight-line distance between two points using the Pythagorean distance formula.Perpendicular Bisector CalculatorThe line that cuts a segment in half at a right angle, with its equation.Percent Grade CalculatorConvert rise and run into percent grade, ratio and degrees — in feet, inches or metric.Roof Pitch CalculatorRise-in-12 pitch, angle, percent and the rafter multiplier for framing.Ramp Slope CalculatorCheck a wheelchair ramp against the ADA 1:12 limit and get the run and landings you need.Pipe Slope CalculatorDrainage fall per foot, percent and ratio — checked against the 1/4 in/ft minimum.