Drilling Mud Weight Calculator

Summary

Convert drilling fluid weight between ppg, psi/ft, kg/L, and specific gravity; calculate hydrostatic pressure at depth; and compute Equivalent Circulating Density (ECD).

How it works

1. Enter mud weight in any unit (ppg, psi/ft, kg/L, or SG) — all other units update instantly.
2. Hydrostatic pressure: P (psi) = mud weight (ppg) × 0.052 × TVD (ft). Enter True Vertical Depth to see the result.
3. ECD adds the annular pressure loss to the mud weight at a given depth: ECD (ppg) = mud weight + (annular pressure loss (psi) / (0.052 × TVD (ft))).
4. Unit conversions: 1 ppg = 0.052 psi/ft = 0.11983 kg/L = 0.11983 SG (water = 8.34 ppg = 1.0 SG).
5. Results update in real time as you type.

Use cases

• Convert a mud weight reading from ppg to psi/ft for pressure gradient analysis.
• Calculate hydrostatic pressure at a given depth to verify overbalance against pore pressure.
• Compute ECD to check whether circulating pressure exceeds the fracture gradient.
• Convert field measurements between metric (kg/L) and US oilfield (ppg) units.
• Verify mud weight is within the safe drilling window between pore and fracture pressures.
• Train drilling engineers on the relationship between mud weight, depth, and wellbore pressure.

Frequently Asked Questions