Work out well drilling cost instantly with clear inputs, formula shown and shareable results.
Rig time is the dominant cost driver: drilling days are depth divided by average rate of penetration times 24, plus non-drilling days for casing, cementing, logging, testing and trouble time. Tangibles and services add roughly 45% on top of rig cost for a conventional well.
Drilling time
Drilling days = depth / (ROP x 24); total days = drilling days + non-drilling days
Cost
Rig cost = total days x day rate; total well cost = rig cost x 1.45
Casing runs, cementing, waiting on cement, logging, formation testing and any stuck-pipe or lost-circulation events all consume day rate without making hole. On difficult wells they can exceed drilling days.
As a benchmark between wells and bit runs. It is most useful for comparing bit and drilling parameter choices, where the trade-off is between penetration rate and bit life.