Missing Size Value in Merchant Center: How to Fix It

What this issue means

Google's specification requires size for Apparel & Accessories > Clothing and Shoes in free listings, and for Shopping ads in those categories when targeting Brazil, France, Germany, Japan, the United Kingdom or the United States. In Merchant Center Next it often appears in the combined apparel issue "Missing value: size [size], color [color], gender [gender], age group [age_group]".

Google's rules for size:

• 1 to 100 characters, one value per product (if you send more, only the first is used)
• Use standard values for your target country: letter sizes (XXS to 6XL), numeric sizes, baby sizes in months (3-6 Mo), toddler sizes (2 Toddler), or one-size values (OSFA, OS, One size)
• No placeholders such as n/a, none or multisize
• Don't put color, material or pattern in size
• Each size variant is a separate product with the same item_group_id

Two optional attributes help Google display sizes correctly: size_system (US, UK, EU and so on) and size_type (regular, petite, plus, tall, big, maternity, oversize).

Why it happens

• Variant option named something else. The Shopify Google & YouTube channel reads the variant option named Size. Options like "Sizes", "Shoe size", "Fit" or a non-English label may not be picked up.
• One-size products have no size option. Hats, scarves and some bags sold in one size don't have a variant, so nothing is sent. For clothing, that triggers the issue.
• Size combined with other options. A single option like "Black / M" means the feed can't separate size from color.
• WooCommerce variation attribute not mapped to size in the Google feed plugin.
• Product wrongly categorized as clothing or shoes. Google auto-assigns categories, and an accessory or home textile may land in a category that requires size.

How to fix it

1. Export the affected list. In Merchant Center, open Products > Needs attention, filter for the size issue, and download the CSV. Group by product type: tops, pants, shoes, one-size accessories.

2. Check the category first. If the product isn't clothing or shoes, set google_product_category to the correct category; size will no longer be required.

3. Add sizes at the source:

   • Shopify (Google & YouTube app): Rename the variant option to Size on affected products. If a product combines size and color in one option, split it into two options (Color and Size). For one-size items, add a Size option with the value One size. Changes sync automatically; confirm in the channel's product list.
   • WooCommerce: Use a global attribute named Size for variations and map it to size in Google for WooCommerce's attribute mapping, or fill the size field in the product's Google attributes. For simple (non-variable) products, enter the size directly.
   • Feed files and supplemental sources: Add a size column per variant row, or upload id and size as a supplemental source.

4. Use standard formats by category. Google's examples:

   • Tops and dresses: XS, M, XL/2XL
   • Pants: 32 Regular, 32W 34L, 00 Waist / 29 Inseam
   • Shoes: 10½ M or 6 4A (letter widths are US and Canada only)
   • Underwear and swimwear: 38 DD
   • Multi-dimension sizes: combine into one value, like 16/34 Tall

5. Add size_system and size_type where useful. If you sell to multiple countries, or sell EU sizes to US shoppers, submit size_system. If you have petite, plus or tall lines, submit size_type rather than putting those words in size.

6. Use attribute rules for clean patterns. If sizes appear consistently at the end of your titles or SKUs (-S, -M, -L), an attribute rule can extract them. Validate a sample before applying it to the whole feed.

How long until it's fixed

After the size data reaches Merchant Center, affected products usually clear within one to three days of reprocessing. If you restructured Shopify variants (for example, splitting a combined option), the channel may treat them as updated products and resync; give it a little longer and check for any new issues on those items.

How to prevent it

• Use the same option names across all products: Size and Color.
• Never combine size and color in a single variant option.
• Give one-size items an explicit size value.
• Build your size charts with standard values your target country recognizes.
• Review new apparel imports in Merchant Center before launching campaigns on them.

Size data affects more than approval; it's how Google shows the right variant to a shopper filtering by size. If your apparel feed needs a cleanup, Mercantads can fix variant structure and attributes through our Merchant Center service, or contact us for an audit.