Dogleg Severity & Minimum Curvature Calculator

Directional drillers and MWD hands run these numbers on every survey. Enter two stations to get dogleg angle, dogleg severity and minimum curvature ΔTVD, northing and easting.

Formulas

Dogleg angleDL = arccos[cos(I₂−I₁) − sinI₁·sinI₂·(1 − cos(A₂−A₁))]

Dogleg severityDLS = DL × 100 / CL

Ratio factorRF = (2 / DL) × tan(DL / 2)

Worked example

GIVEN

Station 1: Inc 10°, Az 45°
Station 2: Inc 13°, Az 50°
Course length 93 ft

WORKING

DL = 3.16°
DLS = 3.16 × 100 / 93

DLS ≈ 3.40°/100 ft

FAQ

Why minimum curvature?

It is the industry-standard survey method (API / ISCWSA) because it models the wellbore as a smooth arc between stations.

Run it with your well data

Field & Metric units, works offline, save and share results with your crew.

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Reference only. Always verify against your company procedures and well-control certification.