Reservoir Pressure Calculator

Choose hydrostatic, gradient, or mud-weight methods quickly here. Enter field data and review unit conversions. Download reports, share results, and refine engineering choices confidently.

Calculator Inputs

Select a method, enter depth and field data, then calculate. Outputs include pressure, gradient, and equivalent mud weight for quick checks.

Choose based on available measurements.
Use TVD for best estimates.
Use 0 for open-to-atmosphere cases.
Standard is 9.80665.
Typical brine is 1000–1200 kg/m³.
Pressure measured at a known depth.
Depth where the reference pressure applies.
Typical normal gradients are ~0.433–0.465 psi/ft.
Use circulating density if available.
Reset
Results appear above this form after calculation.

Formula Used

This tool supports three common field workflows. All methods are computed in consistent units internally, then converted to your selected output.

Hydrostatic Column
P = Psurface + ρ · g · h
ρ is fluid density, g is gravity, h is TVD.
Pressure Gradient
P = Pref + G · (h − href)
Use a measured datum pressure and gradient.
Mud Weight
P = Psurface + ρ(mw) · g · h
Mud weight is converted to an equivalent density.
Derived values:
  • ΔP = P − Psurface
  • Effective gradient = ΔP / h (shown as psi/ft and kPa/m)
  • EMW(ppg) = ΔP(psi) / (0.052 · h(ft))

How to Use This Calculator

  1. Select a method that matches your available field data.
  2. Enter TVD and choose the correct depth unit.
  3. Add surface pressure if the well is pressured at surface.
  4. Provide the method inputs: density, gradient data, or mud weight.
  5. Choose an output unit, then click Calculate.
  6. Use the download buttons to export CSV or PDF reports.

Example Data Table

These examples illustrate typical inputs. Use your measured values for engineering decisions.

Method Depth Key Inputs Surface Pressure Estimated Reservoir Pressure
Hydrostatic 8000 ft ρ = 1030 kg/m³, g = 9.80665 0 psi ≈ 3,611 psi
Gradient 8000 ft Pref = 3500 psi @ 7000 ft, G = 0.465 psi/ft — ≈ 3,965 psi
Mud Weight 10000 ft MW = 10.0 ppg, g = 9.80665 200 psi ≈ 5,400 psi
Hydrostatic 2500 m ρ = 1.10 g/cc, g = 9.80665 0 bar ≈ 270 bar
Values are rounded for readability. Exact results depend on units and inputs.

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Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.