Construction converter
Roof Pitch to Percent Converter
The Roof Pitch to Percent Converter divides the pitch rise by 12 and multiplies by 100. A 6-in-12 pitch equals a 50 percent slope, and the default result is embedded in the page HTML. Percentage slope describes rise over horizontal run; it is not the same as degrees, so compare like units in specifications.
Converted result
50 %
Use percent when drainage or civil notes express slope as vertical change per 100 horizontal units.
| Direction | Formula | Use |
|---|---|---|
| Forward | percent slope = pitch rise ÷ 12 × 100 | Convert the entered source value. |
| Reverse | pitch rise per 12 = percent slope ÷ 100 × 12 | Audit the converted result. |
How to use this construction conversion
Use percent when drainage or civil notes express slope as vertical change per 100 horizontal units. First copy the source value exactly as it appears on the drawing, product label, field note, or supplier document. Record the source unit beside the number. A value without a unit is not a usable construction measurement, even when the arithmetic itself is correct.
Enter the source values in the tool above. The initial example is calculated during the static build and placed directly in the HTML, which makes the number available without JavaScript. Browser code recalculates locally when an input changes; no project measurement needs to leave the device for this conversion.
Forward and reverse check
The forward relationship is percent slope = pitch rise ÷ 12 × 100. The reverse relationship is pitch rise per 12 = percent slope ÷ 100 × 12. Use the reverse formula on the displayed answer whenever a converted dimension will control a cut, layout line, order quantity, or code comparison. A round-trip difference normally reveals premature rounding or a mismatched source unit.
Do not read a 50 percent slope as 50 degrees. The corresponding angle is about 26.565 degrees. Write both the source and converted values on the job sheet. If another person receives only the rounded converted number, they cannot reconstruct the original precision or confirm which conversion was used.
Rounding and field precision
Conversion does not create accuracy that was absent from the measurement. Keep all available digits through the formula, then round the final answer once. Counts and package quantities usually round up. Dimensions should round to the precision supported by the measuring tool, material tolerance, connection detail, and actual work method.
For structural members, stairs, guards, ramps, and roof systems, a unit conversion is only one part of verification. Check the current primary source, local amendments, product instructions, loads, connections, and field conditions. A clean converted number is not an approval of the design.
Related calculator and printable chart
Open the related calculator to place the converted value into a complete formula. The printable chart PDF provides an independent reference that can be stored with the job notes. The HTML chart also exposes every table row without relying on JavaScript.
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