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SMB Tools / Inventory Reorder & EOQ

Never run out, never overstock

Two numbers keep product businesses honest: the stock level to reorder at so you don't run dry while you wait on the supplier, and the order size that keeps ordering and holding costs in balance.

Demand & lead time

Units sold per month
units
Supplier lead time
days
Safety stock
units

Order economics

Cost to place an order
$
Unit cost
$
Annual carrying cost
%
Reorder when stock hits
190 units
order about 329 units each time · ~11.0 orders a year
Order quantity
329 units
Days between orders
33
Avg inventory value
$4,286
Sells ~10.0/day × 14 days lead140 units
Plus safety stock+50 units
Reorder point190 units

A planning estimate that assumes fairly steady demand - for seasonal or spiky items, carry a larger safety stock and revisit as real numbers come in.