Cleaning Supply Usage & Reorder Calculator
Calculate your cleaning supply consumption rate, days of stock remaining, reorder point, and estimated monthly cost.
Formulas Used
Days of Stock Remaining
= Current Stock ÷ Daily Usage Rate
Safety Stock (units)
= Daily Usage Rate × Safety Stock Buffer Days
Reorder Point (units)
= (Daily Usage Rate × Lead Time Days) + Safety Stock
Days Until Reorder Needed
= (Current Stock − Reorder Point) ÷ Daily Usage Rate
Negative value means reorder is already overdue.
Monthly Usage
= Daily Usage Rate × 30
Monthly Cost
= Monthly Usage × Cost Per Unit
Order Cost
= Reorder Quantity × Cost Per Unit
Days of Stock After Reorder
= (Current Stock + Reorder Quantity) ÷ Daily Usage Rate
Assumptions & References
- Daily usage is assumed to be constant (average). Seasonal or event-driven spikes are not modeled.
- A standard 30-day month is used for monthly usage and cost projections.
- The reorder point formula follows standard inventory management practice: ROP = (Average Daily Usage × Lead Time) + Safety Stock (APICS Supply Chain Management body of knowledge).
- Safety stock acts as a buffer against unexpected demand increases or supplier delays.
- Lead time is the number of calendar days from placing an order to receiving it.
- All unit types (bottles, gallons, oz, etc.) are treated equivalently; ensure consistent units across all inputs.
- Cost calculations assume a fixed price per unit with no bulk discount modeled.
- Reference: Tersine, R.J. (1994). Principles of Inventory and Materials Management, 4th ed.