Convert from rise/run
Input rise=0.12m, run=3.0m
Output 4.00%, 2.29°, up 1:25.0
Slope Grade Calculator (Rise/Run, %, Degrees, 1:n)
Convert rise/run, percent, degrees, and 1:n from any single input mode.
All outputs are shown together with per-result copy actions, so field use and handoff stay fast.
Switch across four input modes instantly
View m/mm, ft/in, and 1:n in one screen
Copy each result with one click
How to use
- Choose an input mode: rise/run, percent, degrees, or 1:n.
- Set unit system and display unit (m/mm or ft/in).
- Enter a value and check all converted outputs in the result cards.
- Copy the needed format or copy a shareable link.
Sample
Convert from percent
Input 2.5%
Output 1.43°, up 1:40.0, rise/run=0.025
Formulas
- g = rise / run
- percent = g × 100
- degrees = atan(g) × (180 / π)
- for 1:n, n = 1 / |g|
Reference: drainage and practical notes
- For drainage surfaces, around 1-2% is often cited as a rough reference.
- Recommended values vary by use case, finish, and local standards.
- Always prioritize project requirements, codes, and official specifications.
FAQ
What is the difference between percent and degrees?
Percent is rise over horizontal run, while degrees is angular measure. They may feel close at small values, but they are not the same quantity.
How should I read 1:n?
It means a rise (or fall) of 1 unit for every n units of horizontal run.
How is negative slope handled?
Percent and degrees are shown with sign, while 1:n is shown with a downhill label.
Why can't I enter 90°?
Because tan(90°) diverges, which corresponds to run=0 and cannot be represented in this tool.
Can I view mm/m or in/ft style outputs?
Yes. Use the mixed-unit presets in Advanced and choose mm/m or in/ft.