Shopify Size Recommendation Setup: The Data You Need Before Installing

For a smooth Shopify size recommendation setup, gather one body-measurement size chart per garment type before you install anything. You also need to know which garment type each product belongs to, and which unit your charts use.

With that data ready, the app part takes one sitting. This page covers the preparation only. The install itself, plus try-on, is in the guide to adding virtual try-on to Shopify.

Why does the data matter more than the app?

A size app can only be as good as the chart you give it. ZeDaq.ai measures the shopper from one photo plus their height, then matches those measurements to your chart. If your chart has gaps or mixes garment and body numbers, the suggestion will be off, even when the measurement is right.

Most setup problems trace back to three things:

• charts that list flat garment widths instead of body measurements
• size ranges that don't meet, so some shoppers fall between them
• one chart used for products that fit very differently

What size chart data should you collect?

Collect body measurements: the chest, waist and hips of the person each size is meant to fit. Don't use the measurement of the garment laid flat. A shirt that measures 52 cm across is made for a chest much bigger than 52 cm.

Plan one chart for each garment type you sell. ZeDaq.ai supports four:

Garment type	Typical products	Measurements to enter
Tops	T-shirts, shirts, knitwear	Chest
Outerwear	Jackets, coats	Chest
Dresses	Dresses, jumpsuits	Chest, waist and hips
Bottoms	Trousers, skirts, shorts	Waist and hips

Each size needs a minimum and a maximum. For example, a medium might cover a chest of 96 to 101 cm.

A worked example: cleaning up a dresses chart

Here is an example chart, not a standard. Check your brand's own chart before you copy any numbers.

Size	Chest (cm)	Waist (cm)	Hips (cm)
S	84–89	66–71	90–95
M	89–94	71–76	95–100
L	94–100	76–82	100–106
XL	100–106	82–88	106–112

Notice that each size starts where the last one ends. If small stopped at 88 cm chest and medium started at 90 cm, a shopper at 89 cm would land in neither.

When a shopper's chest says medium but their hips say large, the scan goes with the larger size. It sizes up to the largest relevant measurement, so the garment won't be tight where it matters most.

Which unit and labels should you use?

Pick centimeters or inches for each chart and stay with it. Don't mix units within one chart. If your supplier sends inches and your team works in centimeters, convert the whole chart once and check it twice.

Use the size labels you print on your products. If you sell "UK 10" or "38", enter those labels, not a generic S, M, L. The scan recommends your own labels, so the shopper sees the same size they will pick in the variant menu.

How do you match products to garment types?

Go through your catalog and note the garment type for each product before you install. A quick spreadsheet with product name and garment type is enough.

In the Shopify app embed, the garment type setting is upper body, lower body or dresses. That setting tells the scan which of your charts to use, so a skirt doesn't get sized against your tops chart.

Watch for products that don't fit the obvious group:

• Jumpsuits usually belong with dresses, because chest, waist and hips all matter.
• Oversized hoodies may need their own tops chart with wider ranges.
• Coats worn over knitwear belong in outerwear, not tops.

What should you test once the data is in?

Use Test a shopper in the app before you go live. Type in a few sets of measurements and check the result against what your team would say in a fitting room.

Try these cases:

1. A shopper right in the middle of medium.
2. A shopper on the line between two sizes.
3. A shopper whose hips are one size bigger than their chest.
4. A shopper smaller than your smallest size, or bigger than your largest.

If your range is wide, plan for the edges. The guide to size recommendation for plus-size stores covers charts that run past XL.

What do you need ready on install day?

Use this checklist so nothing stops you halfway:

• A Shopify store on an Online Store 2.0 theme
• One body-measurement chart per garment type
• Ranges that meet with no gaps
• One unit per chart
• Your own size labels
• A list of products by garment type
• A phone to test on a live product page

When that is done, follow the steps to show size recommendations on product pages. If you have questions about themes, embeds or permissions first, see the fitting room app setup questions.

The Free plan includes 3 measurements a month, which is enough to check your charts. Paid plans start with Micro at $14 a month, and each paid plan has a 3-day free trial with no card required. See current plan prices for the rest.

FAQs

Can I install the app before my charts are finished?

Yes. Until you add a chart for a garment type, shoppers get a standard UK, US, EU or AU size. Add your own charts as soon as you can, so the suggestion matches your labels.

Do I need product measurements for every single item?

No. You need one chart per garment type, not per product. Products that share a fit share a chart.

Should I use garment measurements if that's all my supplier gives me?

Not directly. Ask your supplier for the body measurements each size is made for, or work them out with a fitted sample and a tape measure.

Does the shopper need to give their weight?

No. The scan uses one photo and the shopper's height. Their measurements are taken on their own device and matched to your chart.