Sales Velocity
The number of units a product sells per day over a chosen period. It is the base figure behind reorder timing, days of cover and stockout forecasts.
What Is Sales Velocity?
Sales velocity is how fast a product sells, usually expressed as units per day. Most sellers look at it over several windows at once - the last 7, 30 and 90 days - because a single window hides trends and seasonality.
How to Calculate It
Sales Velocity = Units Sold ÷ Days in Stock
Count only the days the product was actually available. If you sold 300 units in a 30-day month but were out of stock for 5 of those days, your velocity is 300 ÷ 25 = 12 units per day, not 10. Dividing by all 30 days understates demand and leads to the next stockout.
Why It Matters
Velocity turns stock on hand into time. Days of cover = Units in Stock ÷ Sales Velocity. With 600 units and a velocity of 12 per day you have 50 days of cover; if your supplier lead time is 60 days, you are already late to reorder.
How SellerLegend Helps
SellerLegend tracks sales velocity across multiple time periods for every product and uses it to give you a recommended purchase date and data-driven reorder quantities.
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