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Cleaning Chemical Calculator
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Days of Supply Calculator

How many days the stock on the shelf covers at the current rate of use.

Inputs

Range: 0.01–100,000 gal

Enter the measured quantity in the unit shown.

Range: 0.0001–1,000 gal

Take it from the issue history for the last three months, not from a guess. Divide by the days the building was actually serviced.

Result

Days of supply at the current rate
40.0 days
Weeks of supply
5.7 weeks
Reading: what this result means for the job
A few weeks of cover. This is the ordinary state for a product with a reliable supplier: the shelf holds what the lead time and the safety days need, and the figure moves with the season rather than with the day.
Applicability limit
The days of supply come from the stock on hand and the average daily use entered, and the average is the weak part: it hides the peak week and the peak is what empties a closet. The stock figure has to be a physical count, including open containers, and the use figure has to be divided by the days the building was actually serviced. This is a planning figure for the values entered, not a measured result. Coverage rates, product yields and application rates are properties of a specific product, applicator and substrate, and the label or data sheet for the product you are using always takes precedence over the default here.
Check before the job

Working

Days of supply at the current rate
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Weeks of supply
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What to check

  • Take the daily use from the issue history over the last three months.
  • Divide by the days the building was actually serviced, not by calendar days.
  • Check the stock figure against a physical count, including open containers.

Related calculators

Days of supply is only as good as the usage rate behind it. An average hides the peak, and the peak is what empties a closet on a Monday, so a rate taken from the last three months of issue history is more useful than a rate taken from last week.