Contour Slope & Gradient Calculator
Calculate slope gradient %, angle (°), and ratio from contour lines elevation rise and horizontal run.
Input Parameters
Calculation Results
Formula & How Contour Slope & Gradient Calculator Works
Closely spaced contour lines indicate a steep slope with a high gradient percentage. Widely spaced contour lines indicate gentle or flat terrain.
- Enter Elevation Change / Vertical Rise (m): Input your target parameter value.
- Enter Horizontal Ground Distance / Run (m): Input your target parameter value.
- Apply Formula: Calculate using
Gradient (%) = (Rise / Run) × 100 | Angle (θ) = arctan(Rise / Run). - Review Results: View exact computed answers, metrics, and worked mathematical proofs.
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Frequently Asked Questions (FAQs)
How do you calculate slope gradient from contour lines?
Count the contour intervals between two points to find total elevation gain (Rise), then measure horizontal distance with a map scale (Run). Gradient % = (Rise ÷ Run) × 100.
What are Eastings and Northings?
Eastings are vertical grid lines on a topographic map (read first, moving left to right). Northings are horizontal grid lines (read second, moving bottom to top).
Authoritative Standards & Verified Reference Citations
Calculations and mathematical logic on this page are grounded in published statutory rules, regulatory standards, and official government data published by the following bodies:
Australian Standards including AS/NZS 3000 (Wiring Rules), AS 3600 (Concrete Structures), and AS 4100 (Steel Structures).
Accreditation and technical guidelines for civil, structural, mechanical, and electrical engineering.
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