Hole Angle Deviation Calculator
Computes toe error from the difference between designed and measured drill-hole angles.
Enter Values
Before you rely on this: First-pass guide only. Verify safety-critical or regulated work against the relevant standards, your project requirements and a qualified professional.
How to use this calculator
- Enter the designed and measured collar angles.
- Enter the hole depth.
- Press Calculate.
How it works
Toe error ≈ hole depth × sin(angle deviation). Small collar-angle errors grow into large toe errors on deep holes.
Worked example
3° off over a 12 m hole. Toe error ≈ 0.63 m.
Frequently asked questions
Why does toe position matter?
Toe errors cause uneven burden at the bench floor — leading to toe (hard digging) or overbreak.
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Cite this tool
Zerdly. (2026). Hole Angle Deviation Calculator. Retrieved from https://www.zerdly.com/tools/hole-angle-deviation-calculator/
Tip: Enter any known values to calculate the remaining results.
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