Slope / Grade Converter

Calculate grade percentage, angle in degrees, and 1:X ratio from rise and run values.

Slope / Grade Converter

Calculate grade percentage, angle in degrees, and 1:X ratio from rise and horizontal run.

Run must not be zero. Negative inputs preserve direction.

Results update instantly

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How to read grade percentage

Grade percentage is the vertical rise divided by horizontal run, converted to percent.

It is commonly used for roads, ramps, and elevation analysis.

Why use the 1:X ratio

The 1:X format shows how many horizontal units are needed for one vertical unit.

It helps standardize slope communication across teams.

Conversion formulas

Grade percent is rise divided by horizontal run, multiplied by 100.

Angle is calculated with arctan(rise / run).

Field and design context

Ramps, drainage, roads, and landscaping can express the same slope in different units.

The 1:X ratio helps teams communicate slope clearly on site.

Real-world example

An 8% grade means 8 units of rise over 100 horizontal units.

That equals about 4.57 degrees.

Limitations

The tool performs mathematical conversion only and does not assess soil, material, or safety factors.

Execution projects still require local standards and engineering review.