A toothpaste tube’s lifespan depends on more than just its size, household size, brushing frequency, and how much you actually squeeze out each time all factor in. This calculator combines them into a clear estimate of how long a tube lasts and what it costs per month.

How to use this toothpaste calculator

1. Enter your Toothpaste Capacity and unit (a standard 4 fl oz tube is about 118 mL).
2. Set your Wastage percentage for paste left in the tube you can’t squeeze out.
3. Enter Pea-Sizes of Toothpaste per wash, Daily Brushes per person, and People in Household.
4. Enter your Toothpaste Price and currency.
5. Read how long the Tube Will Last, plus Monthly Usage and Cost per Month.

What this calculator does

Dentists recommend a pea-sized amount per brushing, about 0.25 mL. For one person brushing twice a day, that works out to roughly 17.5 mL a month, or about 0.6 fl oz. This calculator scales that baseline by your actual household size and brushing frequency, then adds a wastage allowance for the paste that inevitably gets left behind in a tube you can no longer squeeze effectively.

Why wastage matters more than you’d think

A meaningful portion of every tube never actually gets used, it stays trapped near the crimped end or clinging to the inside walls once the tube gets hard to squeeze. Setting an accurate wastage percentage (10% is a reasonable default) keeps the “tube will last” estimate realistic rather than assuming you’ll extract every last drop.

Frequently asked questions