In Short
- Take your size curve from your own sales, not from a generic chart.
- Split each order by that curve, and keep a few units of the slow sizes too.
- Track the stock of every color and size separately during the season, so you see a size sell out right away.
1Why Doesn't an Even Split Work?
Imagine buying a T-shirt in every size from XS to XL, 10 of each. The middle sizes may sell out within a few weeks while the smallest and largest sizes wait on the rack. On one side you lose sales; on the other, unsold stock piles up.
The problem isn't the product; it's how the units are split across sizes. Every store's customers are different: S may lead in one store while L sells more in another. So instead of copying a ratio you heard somewhere else, look at your own sales.
2Take the Curve From Your Own Sales
Add up how many units of each size you sold last season or over the last few months. Each size's share of total sales is your size curve. Watch three things while you do this:
- Sizes that sold out early. Had they stayed in stock, they would have sold more, so their sales understate real demand. Round their share up a little.
- Color differences. M may lead in black while S leads in a light color. If you sell enough, build the curve color by color.
- Promotions. Units sold at a discount can distort the curve of normal weeks. Keep those weeks separate.
Reports › Apparel
Sales by Color × Size
Basic T-Shirt · units sold · darker cell = more sales
3Split the Order Across Sizes
Once you have the curve, split the order quantity by those shares. In the example below, the new-season order for the Basic T-Shirt follows how last season's 120 units were spread across sizes.
Example: An Order of 60 Units
Last season's size shares · Basic T-Shirt
If the math leaves fractions, round the best-selling sizes up and the slow ones down, and check that the total still matches the order quantity.
Keep a few units of the sizes with a small share too. The customer looking for that size should find it as well; a size that's never on the rack is a size you never sell.
4Track the Sizes That Run Low All Season
Placing the order is only half the job. Seeing which size is running low as the season goes on lets you reorder at the right time. For that, you need stock for every color and size, not just for the model: “Basic T-Shirt, 100 units” doesn't tell you which size has sold out.
Products and Stock › Basic T-Shirt › Variants
When a size's stock drops to the threshold you set, add it to your reorder list. Set the threshold with your lead time in mind: if your supplier delivers in a week, you should have enough units on hand to cover a week of sales.
How to Do It in PratikKasa
Apparel module
- Windows
- Android
- iPhone and iPad
- 1
Add the Product With Its Colors and Sizes
Choose the colors and sizes in the product form. Each color and size combination gets its own stock.
- 2
See How Sales Are Spread
Reports › Apparel shows how many units of each color and size you sold, in the color × size table and the size breakdown.
- 3
Set the Low-Stock Threshold
Enter the Low-Stock Threshold in the product's Variants window. A size whose stock drops to that number or below turns yellow in the table; a size that has sold out turns red.
- 4
List the Sizes That Sold Out
In the Windows app, Reports › Apparel › Variant Stock Health shows every sold-out size in one place.
The drawings in this post are based on the screens of PratikKasa 2.1.0.