Reorder Point Calculator

1. Enter the normal and high values in Average daily demand and Maximum daily demand. Use units per day.
2. Enter the two time values in Average lead time (days) and Maximum lead time (days).
3. Select Calculate Reorder Point to run the calculation.
4. Select Reset to clear all four inputs, hide the result, and clear any validation error.

Reorder point formula and safety stock

Average usage during lead time comes from Average daily demand multiplied by Average lead time (days). Safety stock is the maximum-demand usage minus that average usage. The Reorder point is the average usage plus Safety stock.

Average daily demand: 20 units/day
Maximum daily demand: 30 units/day
Average lead time (days): 5
Maximum lead time (days): 8

Average usage during lead time: 100 units
Safety stock: 140 units
Reorder point: 240 units

The calculator writes the formulas as Safety stock = (Max daily demand x Max lead time) - (Average daily demand x Average lead time) and Reorder point = (Average daily demand x Average lead time) + Safety stock.

Reorder level input checks

Each field must contain a number greater than 0. Maximum daily demand must be at least as high as Average daily demand. The same rule applies to Maximum lead time (days) and Average lead time (days). When a check fails, the page shows an error and keeps the result hidden.

Keep the units consistent. The demand fields use units per day, while the lead-time fields use days. Convert weekly records before entering them because the calculator multiplies the values as entered.

Editing any input after a result appears hides the result and clears the stored result text. Select Calculate Reorder Point again to calculate with the new values.

What the reorder point result includes

A valid calculation shows Reorder point (units), Safety stock (units), and Average usage during lead time (units). The Result section also contains Formula used and a table listing the four inputs and the calculated values. Numbers display with up to two decimal places.

Select Copy result to place the plain-text summary on the clipboard. Select Download result (.txt) to create reorder-point-calculator-result.txt. If copying fails, the page displays Could not copy - select and copy manually.

What the four inputs control

• Average daily demand and Average lead time (days) determine Average usage during lead time (units).
• Maximum daily demand and Maximum lead time (days) determine the maximum-demand usage used in the Safety stock (units) calculation.
• The two calculated values combine to produce Reorder point (units), which the Result section displays with the assumptions.

When another inventory calculator fits better

Use the Business Calculators page to browse the category. Choose the Economic Order Quantity Calculator for an order quantity based on demand, ordering cost, and holding cost. Choose the Inventory Planning Calculator for reorder point, safety stock, economic order quantity, and inventory turnover in one calculation. Use the Inventory Turnover Calculator when your inputs are cost of goods sold and average inventory.

Frequently asked questions