Par level calculator

Par level

Par = daily usage × (lead time + days between deliveries) + safety buffer

Reorder point

Reorder point = daily usage × lead time + safety buffer

Safety buffer as a percent

Buffer in units = percent × daily usage × days between deliveries. Cycle usage is daily usage × days between deliveries.

What each input means

Average daily usage is what left stock on ordinary days: the recipes you sold, the waste you logged, and transfers out, divided by the number of those days. Purchases are what arrived, not what you used. A festival week is not an ordinary Wednesday. The method is in how to set par levels from usage.

Supplier lead time is days from the order to the delivery you can put away. It is that supplier’s habit for that branch. Days between deliveries is the order cycle: how many days pass from one delivery to the next. Lead time is how long the order takes. The gap between trucks is separate, and it is what makes the par higher than the reorder point.

The safety buffer is extra stock for a late truck or a full service. Enter it in the same unit as usage, or as a percent of cycle usage. Cycle usage is daily usage × days between deliveries. A percent is turned into units before either result is calculated. The unit is kilograms, litres, or pieces, the same unit you count and the same unit you order.

Example (illustrative numbers)

Daily usage 5 kg, supplier lead time 3 days, days between deliveries 4, safety buffer 5 kg. Reorder point = 5 × 3 + 5 = 20 kg. Par = 5 × (3 + 4) + 5 = 40 kg. These are the same illustrative figures as how to set par levels from usage. They are not a customer result and not a recommended cover.

The same usage with a safety buffer of 20% of cycle usage: cycle usage is 5 × 4 = 20 kg, so the buffer is 4 kg. Reorder point = 5 × 3 + 4 = 19 kg. Par = 5 × (3 + 4) + 4 = 39 kg. The 20% is only to show the percent toggle. It is not a suggested buffer.

Choosing a safety buffer

Make the buffer larger when lead time is long or the truck is unreliable. Imported goods are the usual case: a missed sailing is days, not a morning. Make it smaller when the item arrives fresh every day and a missed delivery is obvious before service. Write the buffer in units, or as a percent of usage over the days between deliveries. Do not copy a percent from another restaurant and call it a standard. This page does not suggest one.

One par per branch

Each branch needs its own par, because usage is not the same kitchen. A second site that sells half as much does not share the first site’s par. A spreadsheet can hold one par. It breaks when each branch has its own usage, someone overwrites the formula, and the next site never gets the change. restaurant inventory management software keeps the count and the reorder point on the branch that holds the stock.

Set a par level and a reorder point

Turn average daily usage, supplier lead time, days between deliveries, and a safety buffer into a par level and a reorder point. Inputs stay in the link.

1. Name the item and the unit. Use kilograms, litres, or pieces, the same unit you count and the same unit you order. A par in cases and a count in kilograms will not reorder the right amount.
2. Enter average daily usage. Usage is what left stock over ordinary days: recipes sold, waste logged, and transfers out, divided by the number of those days. A festival week is not an ordinary day. Purchases are what arrived, not usage.
3. Enter lead time and days between deliveries. Supplier lead time is days from the order to the delivery you can put away. Days between deliveries is the order cycle: how many days pass from one delivery to the next.
4. Add a safety buffer. Enter the buffer in the same unit as usage, or as a percent of cycle usage. Cycle usage is average daily usage × days between deliveries. A percent is converted to units before either result is calculated. Zero is a valid buffer.
5. Read the par level and the reorder point. Reorder point = daily usage × lead time + safety buffer. Par = daily usage × (lead time + days between deliveries) + safety buffer. Order when on-hand stock falls to the reorder point, enough to return to par, in the pack size the supplier sells.

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