Bath calculator

Estimate the water, then read the label.

Rectangular volume overstates most tubs, so this model exposes a shape adjustment and reminds you to allow for displacement.

Interior length (inches)

Average interior width (inches)

Filled depth (inches)

Shape adjustment (%)65% accounts approximately for sloped sides and body displacement.

Estimated working volume

About 66 gallons

This is a rough geometry estimate—not a dosing instruction. Follow the finished product label. Stop filling below overflow hardware and allow for body displacement.