Calculator

Kill Sheet Calculator

Use this after shutting in on a kick to calculate kill mud weight and circulating pressures — the same core math taught in IWCF and IADC well control certification.

🚨 Kill Sheet Calculator

Requires the well to already be shut in with SIDPP recorded. See the shut-in procedure if you haven't done this yet.

Formation Pressure—
Kill Mud Weight—
Initial Circ. Pressure (ICP)—
Final Circ. Pressure (FCP)—
This is a reference tool, not an operational authority. Real well control decisions must be made by your certified well control supervisor following your company's approved procedures. Never act on a kill sheet calculation from a website alone during an actual well control event.

The Formulas Used

Formation Pore Pressure
FPP = SIDPP + (OMW × 0.052 × TVD)
Direct measurement of excess formation pressure above hydrostatic once the well is shut in.
Kill Mud Weight
KMW = OMW + (SIDPP ÷ (0.052 × TVD))
The mud weight required to exactly balance formation pressure at the bit.
Initial Circulating Pressure
ICP = SIDPP + Slow Pump Rate Pressure
The standpipe pressure to hold at the start of the kill circulation.
Final Circulating Pressure
FCP = (KMW ÷ OMW) × Slow Pump Rate Pressure
The standpipe pressure once kill mud has fully displaced the wellbore.

What Is Slow Pump Rate Pressure?

SPR (also called SCR — slow circulating rate pressure) is the standpipe pressure recorded at a reduced, standardized pump rate — measured routinely during normal operations specifically so it's available if a kick occurs. Without a current SPR reading, ICP and FCP can't be calculated accurately, which is why crews record it every shift as standard practice.

For the full step-by-step shut-in procedure and the difference between the Driller's Method and Wait-and-Weight, see the well control reference page.