Below are the creative requirements for Google Discovery ads:

  1. Set up your single-image ad (Discovery Standard Ads)
  2. Set up your multi-image carousel ad (Discovery Carousel Ads)
  1. Discovery Standard Ad Assets Specifications

Headline
 (required)

Headlines can be up to 40 characters. You can enter up to 5 headlines for a single creative.

Description
 (required)

Descriptions can be up to 90 characters. You can enter up to 5 descriptions for a single creative.

Images
 (required)

To get the greatest reach, upload multiple 1.91:1 landscape images. You can upload up to 20 marketing images for a single creative.

  • Landscape image (1.91:1): Min size: 600x314. Recommended: 1200x628. 5MB max file size
  • Square image (1:1): Min size: 300x300. Recommended: 1200x1200. 5MB max file size
  • Portrait (4:5): Min size: 480 x 600. Recommended: 960 x 1200
  • * Note that Portrait (4:5) images won't appear on YouTube
  • The maximum file size is 5MB and the supported file types are JPG, PNG, and static GIF.

Business Name
 (required)

Only one business name. It can be up to 25 characters.

Logos
 (required)

Upload 1:1 square logos. The recommended dimensions are 1200 × 1200, but logos can be as small as 128 × 128 The maximum file size is 5MB

Final URL
 (required)

Default landing page that customers will reach on clicking the ad.

  1. Discovery Carousel Ad asset specifications

 

Headline
 (required)

Headlines can be up to 40 characters. Related to each images

Description
 (required)

They can be up to 90 characters. Which will be combined with any of your headlines, images and landing page.

Card images
 (min 2 cards, max 10)

Require Category wise/Product wise images for each card. Landscape, square & Portrait images for each category/product specific.  

  • Landscape image (1.91:1): Min size: 600x314. Recommended: 1200x628. 5MB max file size
  • Square image (1:1): Min size: 300x300. Recommended: 1200x1200. 5MB max file size
  • Portrait (4:5): Min size: 480 x 600. Recommended: 960 x 1200

Business Name
 (required)

Only one business name can be provided for a single creative. It can be up to 25 characters.

Logos
 (required)

Upload 1:1 square logos. The recommended dimensions are 1200 × 1200, but logos can be as small as 128 × 128. The maximum file size is 5MB

Final URL
 (required)

You can provide a specific landing page for each image.

 

 

https://s3.amazonaws.com/cdn.freshdesk.com/data/helpdesk/attachments/production/48058556296/original/0LOfUuTC0H08h1ZjNNiDuUoztLrUZBBkMg.png?1599831800

 

https://s3.amazonaws.com/cdn.freshdesk.com/data/helpdesk/attachments/production/48058556495/original/dP7R6qpOeUJaeULf7WhrAZ3sD0XszITo2g.png?1599831860

Refer to this link to learn about creative asset quality guidelines for discovery ads - https://support.google.com/adspolicy/answer/9311119?visit_id=637475166674913222-3224430719&rd=1