Reddit Ad Specs: A Complete Guide for Marketers

Reddit has grown into one of the most influential online communities, with over 100,000 active subreddits and millions of daily users. This platform is known for its niche communities, engaged audiences, and high potential for targeted advertising. For brands looking to advertise on Reddit, understanding Reddit ad specs is crucial to ensure that campaigns look professional, load quickly, and meet the platform’s creative guidelines.

In this guide, we’ll break down the essential ad specifications for different Reddit ad formats, so you can design effective creatives and maximize engagement.

1. Overview of Reddit Ad Formats

Reddit offers multiple ad formats to suit different marketing goals:

1. Promoted Posts (Link Ads) – Drive users to an external landing page or content.

2. Promoted Posts (Text Ads) – Engage users directly within Reddit by encouraging discussion in the comments.

3. Image Ads – Highlight a single image with supporting copy.

4. Video Ads – Tell a story using motion and sound.

5. Carousel Ads – Feature multiple images or videos in one ad unit.

6. Conversation Ads – Designed to spark discussion within a subreddit.

Each of these formats comes with its own technical specifications, which advertisers must follow for optimal performance.

2. Image Ad Specs

Recommended size: 1200 x 628 pixels (landscape)
Aspect ratio: 1.91:1
File types: JPG or PNG
Max file size: 3 MB
Headline length: Up to 300 characters (only 150 visible before cut-off)

💡 Tip: Use high-resolution images with minimal text overlay to comply with Reddit’s visual guidelines and ensure clarity across devices.

3. Video Ad Specs

Resolution: Minimum 600 x 338 pixels, recommended 1920 x 1080 pixels
Aspect ratio: 16:9 (landscape) or 1:1 (square)
File types: MP4 or MOV
Max file size: 1 GB
Video length: 5 seconds to 30 minutes (shorter videos generally perform better)
Thumbnail: JPG or PNG, 1200 x 675 pixels recommended

💡 Tip: Always upload captions since many Reddit users watch videos with sound off.

4. Carousel Ad Specs

Carousel ads allow advertisers to showcase multiple slides within a single ad unit.

Image size: 1080 x 1080 pixels (square) or 1200 x 628 pixels (landscape)
Aspect ratio: 1:1 or 1.91:1
Max slides: 2–6 per carousel
File type: JPG or PNG
Max file size: 3 MB per image

💡 Tip: Ensure consistent branding across all slides to maintain a cohesive experience.

5. Text Ad Specs

For Reddit’s Promoted Text Posts, there’s no image requirement, but copy guidelines are strict:

Title: Up to 300 characters (truncated at 150)
Body text: Unlimited characters, but concise content performs best
Formatting: Supports markdown for links, bold, italics, and lists

💡 Tip: Write titles that blend naturally into subreddit discussions to avoid being ignored as an ad.

6. General Reddit Ad Design Guidelines

To meet Reddit’s advertising standards and ensure your creatives pass approval:

• Avoid misleading or clickbait titles

• Keep text overlays minimal (especially on images)

• Respect subreddit rules and tone when targeting specific communities

• Ensure branding is clear but not overpowering

• Optimize files for fast loading on mobile devices

7. Why Following Reddit Ad Specs Matters

Ad specs aren’t just about dimensions and file sizes—they directly affect your campaign performance. Incorrect sizing can lead to cropped visuals, distorted images, or disqualification during review. Following Reddit’s official ad specifications ensures:

• Better user experience – Ads appear sharp and well-formatted across all devices.

• Higher engagement rates – Proper formatting keeps the audience focused on the message.

• Approval speed – Compliant ads are approved faster, reducing campaign delays.

Final Thoughts

Reddit is a goldmine for advertisers looking to connect with highly targeted communities. But to succeed, your creatives must meet Reddit’s ad specs precisely. Whether you’re running image ads, videos, or carousel campaigns, following the correct dimensions, file formats, and content guidelines will help you make the most of Reddit’s unique advertising environment.