Reddit Carousel Ads — Image Sizes for Card, Compact and Conversation Mode

Your Reddit ads can be displayed using a Single Image, Video, or a Carousel of multiple images. The carousel format may appear differently depending on the chosen slide size. Below, we provide the technical specifications for image sizes in Carousel Ads across In-feed, In-banner, and In-conversation placements in Reddit Ads.

Headline for Carousel Reddit Ads

Regardless of which image size you choose, you can use a Headline that applies to all slides. It is displayed above the slides and can be up to 300 characters long. Reddit recommends keeping the text within 150 characters.

• Maximum length: 300 characters
• Recommended length: ≤ 150 characters
• Quantity: 1
• Required: Yes

Captions

Along with the main headline, you can add a Caption of up to 50 characters. This short text appears under each slide and can be unique per slide. In some formats, only one of the uploaded captions will be displayed.

• Maximum length: 50 characters
• Quantity: 1 per image
• Required: No

Destination URLs & Call to Action

Each slide may link to a unique landing page. A Call to Action button can also be set individually for each slide.

Number of Slides

You can use between 2 and 6 slides. Each slide includes an image, headline, and link, allowing you to highlight different features, categories, or options of your product.

Image Specifications

Images may use different aspect ratios. Below are the recommended specifications.

Cross-device

• Portrait 4:5 — 1200 × 1500 px
• Landscape 4:3 — 1440 × 1080 px
• Landscape 16:9 — 1920 × 1080 px

Mobile

• Square 1:1 — 1200 × 1200 px
• Portrait 4:5 — 1200 × 1500 px
• Landscape 4:3 — 1440 × 1080 px
• Landscape 16:9 — 1920 × 1080 px

Desktop

• Portrait 4:5 — 1200 × 1500 px
• Landscape 4:3 — 1440 × 1080 px
• Landscape 16:9 — 1920 × 1080 px

Thumbnail (for compact view)

The thumbnail is automatically generated from the first carousel image but can be replaced manually.

• Accepted formats: JPG, PNG, GIF
• Maximum file size: 3 MB

Recommended resolution

• Landscape 4:3 — 400 × 300 px
• Square 1:1 — 300 × 300 px