Form Grade & Elevation Calculator
Calculate target elevations along a run from a starting elevation and specified slope.
Editorial review: 2026-09-29 · How we review technical content
Key takeaways
- Generate target elevations at regular stations along a straight uniform slope.
- Complex grading, crowns, valleys, vertical curves, drainage structures, and survey-control requirements need project-specific layout.
Form Grade & Elevation Calculator
Generate target elevations at regular stations along a straight uniform slope.
What this calculator does
Generate target elevations at regular stations along a straight uniform slope.
The tool applies the entered percent grade to each station from the starting elevation and produces a small staking/check table. Positive slope is treated as falling away from the starting elevation.
How to use the result
Complex grading, crowns, valleys, vertical curves, drainage structures, and survey-control requirements need project-specific layout.
How this calculator works
The tool applies a uniform percent slope from a starting elevation and generates station elevations at the entered interval.
Real surfaces may use multiple planes, crowns, valleys or transitions. Do not force a complex drainage surface into one straight-line grade.
Input checklist
- Starting elevation: Enter the project-specific starting elevation in ft.
- Run distance: Enter the project-specific run distance in ft.
- Slope: Enter the project-specific slope in %.
- Stake interval: Enter the project-specific stake interval in ft.
Worked example
At 1.5% fall, elevation drops 0.015 ft per horizontal foot; over 30 ft the total drop is 0.45 ft.
Field checklist
- Confirm benchmark datum.
- Use horizontal station distance.
- Check direction of fall before setting forms.
- Field-verify with appropriate survey/laser equipment.
References & further reading
- ACI SPEC-301-20 — Specifications for Concrete Construction — Reference specification used when incorporated into project specifications.
- NRMCA Concrete In Practice (CIP) — Industry education covering common concrete field problems and practices.
- ACI PRC-302.1-15 — Guide to Concrete Floor and Slab Construction — Construction guidance for slabs-on-ground and suspended floors.
- ACI PRC-360R-10 — Guide to Design of Slabs-on-Ground — Planning/design reference for nonstructural slabs-on-ground; structural slabs may fall under ACI 318.