Size grids
How to read an apparel size grid on a wholesale order
Buyers write clothing orders as compact grids: a row per style and color, a number per size. Here is how to read size runs, prepacks and buyer shorthand, and how to turn them into the right Shopify variants every time.
Key takeaways
- A size grid is the style × color × size table on an apparel PO. Each filled cell becomes one Shopify variant with its own quantity.
- A prepack is a fixed bundle of sizes. Quantities ordered in packs must be multiplied out before they become units.
- Most size mistakes come from three places: the buyer's size order differs from yours, a size isn't offered in that color, or packs are read as pieces.
What is a size grid?
On a wholesale purchase order for clothing, each line is usually one style in one color, and the sizes run across the line. That table of styles, colors and sizes is the size grid. The set of sizes a style comes in, and how many of each the buyer wants, is the size run.
| Style | Color | XS | S | M | L | XL | Units |
|---|---|---|---|---|---|---|---|
| Field jacket | Olive | 2 | 3 | 3 | 2 | 10 | |
| Field jacket | Navy | 1 | 2 | 2 | 1 | 6 | |
| Rib tee | Cream | 2 | 4 | 4 | 2 | 12 |
Those three rows are 12 separate Shopify variants (Field jacket / Olive / S, Field jacket / Olive / M, and so on), each with its own quantity. Blank cells are sizes the buyer didn't order, not zeros to type.
Size systems you will see on apparel POs
- Letter sizes: XXS, XS, S, M, L, XL, 2XL, 3XL. Watch for "XXL" versus "2XL" and "1X" in extended sizes.
- Numeric women's sizes: 0, 2, 4, 6, 8 and up, or 24 to 34 for denim waist sizes.
- Kids' sizes: baby sizes by months (0–3M, 3–6M), toddler sizes (2T, 3T, 4T) and kids' sizes (4, 5, 6, 7, 8, 10, 12, 14). "4" and "4T" are different sizes, so they must not be merged.
- Menswear: waist × inseam for trousers (32×30, 32×32) and chest plus length for tailoring (40R, 42L).
- One size: hats, scarves, bags. Often written as "OS" or "O/S".
How buyers write sizes in shorthand
Buyers rarely copy your line sheet exactly. The same order can arrive in any of these forms:
- Slash runs: "S/M/L 2/4/2" means 2 S, 4 M, 2 L.
- Dash runs: "1-2-2-1" next to a style offered in S to XL means 1 S, 2 M, 2 L, 1 XL. You have to know the style's size range to read it.
- Ranges: "S–XL, 2 each" means 2 of every size from S to XL, including M and L.
- Nicknames: "Lg", "Med", "X-Lrg", "Sm" for letter sizes, and color names that drift ("Sage" for "Sage Green", "Oat" for "Oatmeal").
- Handwriting: at trade shows, a size grid is often filled in on a paper form, so a 1 and a 7, or a 4 and a 9, are easy to confuse.
Prepacks: when one unit is not one piece
A prepack is a fixed bundle of sizes sold as one unit, often used for basics and kids' wear. A brand might sell a tee in a "1-2-2-1" prepack: one S, two M, two L and one XL, six pieces per pack.
| Size | Per pack | × 3 packs |
|---|---|---|
| S | 1 | 3 |
| M | 2 | 6 |
| L | 2 | 6 |
| XL | 1 | 3 |
| Total pieces | 6 | 18 |
If the PO says "3" and you enter 3 pieces, the buyer gets a sixth of what they ordered. Always check whether a quantity is in packs, cases or pieces, and whether the price is per pack or per piece.
Five mistakes to watch for
- The buyer's size order differs from yours. A grid headed "L, M, S" read in your usual S-M-L order flips the whole run.
- The size doesn't exist in that color. Some colors are cut in a shorter run. If the buyer ordered XL in a color that stops at L, it needs a decision, not a guess.
- Packs read as pieces, or pieces read as packs.
- Kids' sizes merged. 4T and 4 are different products in many catalogs.
- A row total that doesn't add up. If the buyer wrote a units total, add up the cells. A mismatch means one cell is misread.
Set up Shopify variants so every PO is easier
Matching PO lines goes faster, by hand or with software, when the catalog is consistent:
- Use the same option names on every product, such as
ColorandSize, in the same order. - Use one spelling for each size across the catalog: pick "XL" or "X-Large", not both.
- Use a SKU pattern that includes style, color and size, for example
FJ-OLV-M. Many buyers copy SKUs onto their POs. - Keep a short list of the color nicknames your buyers use, and which catalog color each one means.
This is the problem Orderseam was built around. It reads size grids, prepacks and buyer shorthand from any PO format, matches every cell to the right Shopify variant, remembers how each buyer writes things, and flags anything it can't be sure of instead of guessing.
Common questions
- What is a size run in apparel wholesale?
- A size run is the set of sizes a style is offered in, and the quantity ordered in each, for example S/M/L/XL ordered as 1/2/2/1. On a wholesale PO it is usually written as one row per style and color, with a column or number per size.
- What is a prepack in apparel?
- A prepack is a fixed bundle of sizes sold as one unit, for example one pack containing 1 S, 2 M, 2 L and 1 XL, which is 6 pieces. A buyer who orders 2 packs is ordering 12 pieces, so the quantity on the PO has to be multiplied by the pack's size ratio before it goes into Shopify.
- How should size variants be set up in Shopify for wholesale?
- Use the same option names on every product (for example Color and Size), the same size labels across the catalog, and a SKU pattern that includes style, color and size. Consistent variants make every PO line faster to match, by hand or automatically.
Let Orderseam read the size grids
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