In the previous article, we learned about the must-required attributes and attributes based on conditions.  Now, let’s move a step further and understand optional attributes in Google Merchant Center.  Optional attributes in a Google shopping feed provide additional product data that makes your product stand out.

By adding the right optional product attributes, Google can better understand your products and increase conversion rates.

Although it is not mandatory to add these attributes, you can significantly enhance product visibility and optimize your ad performance by adding them.

What are some of the key optional attributes?

Let’s explore some key optional attributes that are essential to submit to the Google Merchant Center for better feed optimization:

1. Additional Images [additional_image_link]

It provides a URL for an additional image of your product. Up to 10 additional images can be added.  The image can show the product in use or include graphics and illustrations. For AI-generated images, you must have metadata indicating AI generation.

E.g. http://www.example.com/image1.jpg

2. Product Highlights [product_highlight]

It provides a short bulleted list of the most relevant highlights of your products. The product highlights are short and quick to read, and answer the most common questions about the product. Each product must have at least 2 and can have at most 100 product highlights.

E.g. 

• Made from 100% organic cotton.
• Soft, breathable fabric with a relaxed fit.
• It features a stylish embroidered logo on the chest.

3. Product Details [product_detail]

Product detail attributes help to find more technical specifications and additional details of the products, which helps to improve the accuracy of search results.  This attribute allows a quick read of individual products based on their query.

It has three sub-attributes:

• Section name [section_name] (Optional but recommended)
• Attribute name [attribute_name] (Required)
• Attribute value [attribute_value] (Required)

E.g. if running shoes are made of recycled material, then it is submitted as
Sustainability: material: recycled

4. Lifestyle Image [lifestyle_image_link]

Lifestyle images include images of the product in a real-world setup, which can be shown to the shoppers in the free listing results.  It allows for showcasing the image of the product, helping potential customers visualize how the product fits into their daily lives.

E.g. Image of a flower vase in the room 

lifestyleImageLink”: “https://www.example.com/flowervase.jpg

5. Size System [size_system]

Make sure your sizing system is crystal clear. This attribute depends on the product category, for example such as apparel or shoes.  Whether it’s US, UK, or EU sizes, this ensures customers pick the right fit and avoid the hassle of returning the product.

E.g. US, UK, EU, etc.

6. Custom labels [custom_label_0-4]

These attributes help create filters in reporting and bidding for shopping campaigns but aren’t displayed to customers.  Custom labels can be used to subdivide your shopping campaigns. You can create up to 5 custom labels and can create up to 1000 unique labels in each custom label.

Eg.
▻ Custom label 0 [Custom_label_0] Summer
▻ Custom label 1 [Custom_label_1] Winter
▻ Custom label 2 [Custom_label_2] Monsoon

7. Cost of Goods Sold [cost_of_goods_sold]

This includes costs for selling a product, such as material, labor, freight, or overhead. It helps improve the overall ranking and enhances the data.  It calculates the estimated gross profit of your product.

8. Unit Pricing Measure [unit_pricing_measure]

This attribute represents the measurement and dimension of a product as it is sold. It provides information about the price per unit of the product.  That helps shoppers to know the per-unit pricing of the product. Use the unit pricing base measure attribute to include the denominator for your unit price.

For example, if you are selling a 150 ml bottle of perfume, unit pricing helps to know how much your perfume costs per 100 ml.

9. Shipping Label [ Shipping_label]

This is a label you assign to a product to categorize it to help assign correct shipping costs in your Merchant Center account settings. It is not visible to customers.

For example, if your store carries both perishable and non-perishable products, their shipping needs are naturally different.  To handle this smoothly, you can assign distinct shipping labels to each product category, like perishable and non-perishable, and set up tailored shipping settings for timely and cost-effective delivery of the product.

10. Shipping width [shipping_width]

This is all about your product’s packaging.  Adding shipping width helps calculate accurate shipping costs, especially for bulky or oversized items.

E.g., 30 cm, 12 in

11. Product Length [product_length], Product Width [product_width], Product Height [product_height]

It shows the length, width, and height of your product. If your product’s width, length, or height matters, like for furniture, packaging, or anything with specific dimensions, make sure to add this attribute.  Adding product height along with width and length ensures customers understand the product’s size accurately.

E.g. Product width: 20 cm, 8 in
Product length: 10 cm, 5 in
Product height: 20 cm, 8 in

12. Return Policy Label [return_policy_label]

Clear return policies build trust. By adding a return label, you can easily apply the right return rules for different products.  It keeps everything organized and helps shoppers know what to expect.

13. Certification [certification]

If your products require specific energy ratings, it shows your product with a supported energy efficiency rating certification to be shown in the free listing or Google ads.

E.g., A+++, B, C

14. Promotion ID [promotion_id]

If you are running a sale or a special offer, use this attribute. Tag your products with a promotion ID so Google knows which discounts apply. This makes sure your deals get the visibility they deserve.

E.g.   black dress_end of summer sale

15. Free shipping threshold [free_shipping_threshold]

It tells Google and customers the minimum order value needed to qualify for free shipping and often encourages bigger purchases.

E.g. $50, €40

16. Tax category [tax_category]

Different products often mean different tax rates. Use the tax category attribute that classifies your product by specific tax rules to keep everything compliant and avoid hassle later.

E.g., Clothing, Electronics, Books, Apparel

17. Mobile link [mobile_link]

This attribute is essential for a mobile-optimized landing page when you have different URLs for desktop and mobile. It ensures that your landing page looks right on a mobile device. These types of sites often load faster on mobile devices.

E.g. https://mobile.example.com/writing

Let’s Understand the Optional Attributes with an Example

Suppose you’re running an online store that sells electronics, specifically Smart TVs. Let’s see how to submit optional attributes and make your product feed more informative and attractive.

• Product ID:   SmartTV-2025
• Product Title:  XYZ 55-Inch 4K UHD Smart TV – Vision & HDR10
• Additional Image Link:  http://www.example.com/images/xyz-55in-sideview.jpg
• Lifestyle Image Link:  http://www.example.com/images/xyz-55in-lifestyle.jpg
• Product Highlight
  • Ultra HD 4K resolution with HDR10 support
  • Built-in Google Assistant and AI compatibility
• Energy Efficiency Class: A++
• Size System: US
• Shipping Label: Fragile
• Free Shipping Threshold: $500

Final Thoughts

Adding the above attributes, like images, highlights, and lifestyle images in your feed, can give customers a clear picture of what you’re selling. Even information like shipping labels and return policy labels, while not directly seen by customers, helps you manage your listings effectively.

By including these optional attributes, you help Google better understand your products, which can lead to them being shown to the right people. Managing all these details might seem like a lot, but using an automated tool such as the Simprosys Google Shopping Feed app can simplify the process of adding and updating this valuable information.

Ultimately, using optional attributes is a great way to optimize your product data feed and potentially improve your ad performance and sales.