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Roof Pitch Calculator

Enter your values below to get the result first, then scroll for the full explanation and guidance.

Step 1 • Add values

Use the calculator

Enter your values below to generate an instant result. You can update the inputs at any time to compare different scenarios.

Example: 1 m rise over 2 m run gives a pitch of 26.57 degrees.

Results refresh instantly as values change.

Angle from horizontal

26.57°Right-triangle rise and run

Angle from horizontal: 26.57° (Right-triangle rise and run)

The angle is arctan(rise divided by horizontal run). Both dimensions must use the same unit.

Slope measurements

The angle is arctan(rise divided by horizontal run). Both dimensions must use the same unit.

Result snapshot

A quick visual read of the values behind this result.

Rise1 m
Horizontal run2 m

Recommended next checks

  • →Use a horizontal run, not the sloping length.
Rise
1 m
Horizontal run
2 m

Try different values to compare results.

Enter the vertical roof rise and horizontal run to calculate pitch in degrees. This is a geometry result, not a roof design approval.

Inputs and units stated

Formula shown

Scope limits explained

Table of Contents

6

About Roof Pitch Calculator

Roof Pitch Calculator helps you work through the main numbers for this topic quickly with a simple input flow and an instant result.

Use the calculator result as a practical starting point, then review the explanation and assumptions on the page if you want more context.

Roof pitch formula

Pitch angle = arctan(rise / horizontal run). For 1 m over 2 m, the angle is 26.57 degrees after rounding.

Formula explained

Angle from rise and run

Calculate roof pitch in degrees from vertical rise and horizontal run.

Formula

Angle = arctan(rise / horizontal run)

How the result is built

1Enter the labelled values using the stated units.
2Apply Angle = arctan(rise / horizontal run).
3Read the result alongside the page assumptions and scope limits.

Example

Example: 1 m rise over 2 m run gives a pitch of 26.57 degrees.

Assumptions

  • Rise and run form a right triangle and use the same unit.
  • This is a geometric angle, not a structural or building-regulation assessment.

Source basis

  • Right-triangle trigonometry

FAQ

Common questions

No. Run is measured horizontally; the sloping rafter length is a different dimension.

Trust and notes

Assumptions and important notes

This calculator is designed to give a fast estimate using the method shown on the page. Results are most useful when your inputs are accurate and the tool matches your situation.

Use the result as guidance rather than a final diagnosis or professional decision. If the result could affect health, legal, financial, or compliance decisions, verify it with a qualified source where appropriate.

  • Rise and run form a right triangle and use the same unit.
  • This is a geometric angle, not a structural or building-regulation assessment.

Method

Angle from rise and run

Last reviewed

October 12, 2026