Reddit ad specs for 2026: image ads at 1080x1350 pixels (4:5 portrait, max 3MB JPG/PNG), video ads at MP4/MOV up to 1GB (15-min max, 30 FPS, H.264 recommended), headlines at 150 characters for feed placements and 100 characters for conversation placements. Since 70%+ of Reddit usage is mobile, 4:5 portrait is the optimal ratio for most campaigns. Improperly sized creative gets cropped or rejected, so bookmark this page as your quick-reference guide.

What Are the Reddit Ad Formats and Their Key Specs?

Reddit offers several ad formats, each with specific creative requirements:

Ad Format

Best For

Key Specs Summary

Image Ads

Static promotional content

1080x1080 to 1920x1080, max 3MB

Video Ads

Engaging storytelling

Up to 15 min, max 1GB, 30 FPS

Carousel Ads

Multi-product/feature showcase

2-6 cards, same image specs

Conversation Ads

Native thread placement

Appears in comment sections

Takeover Ads

Premium brand awareness

Custom specs, contact Reddit

Reddit Ad Formats Overview

Image Ad Specs

Image ads are the most common Reddit ad format. For context on what Reddit advertising costs across all formats, see our Reddit advertising cost guide. Here are the complete specifications:

Image Dimensions

Reddit supports multiple aspect ratios for image ads:

Aspect Ratio

Dimensions

Best Use

1:1 (Square)

1080 x 1080 px

Mobile-first campaigns

4:5 (Portrait)

1080 x 1350 px

Mobile feed visibility

4:3 (Landscape)

1440 x 1080 px

Desktop-friendly content

16:9 (Widescreen)

1920 x 1080 px

Cinematic visuals

Recommended: 4:5 portrait or 1:1 square ratios perform best on mobile, where 70%+ of Reddit usage occurs.

Image File Requirements

Specification

Requirement

File Types

JPG, PNG

Maximum File Size

3 MB

GIF Support

Accepted but converted to static image

Minimum Resolution

300 x 300 px

Color Space

sRGB recommended

Image Ad Text Requirements

Element

Character Limit

Notes

Headline (Feed)

150 characters max

Displays in user feeds

Headline (Conversation)

100 characters max

For conversation placement

Body Text

Optional, varies by placement

Keep concise

Display URL

Automatically generated

From destination URL

Best practice: Keep headlines under 100 characters to ensure full visibility across all placements.

Video Ad Specs

Video ads on Reddit are highly engaging and support a range of formats. Understanding reddit video ads specifications ensures your content displays perfectly across all placements.

Video Dimensions

Aspect Ratio

Dimensions

Best Use

1:1 (Square)

1080 x 1080 px

Balanced mobile/desktop

4:5 (Portrait)

1080 x 1350 px

Best for mobile (recommended)

4:3 (Landscape)

1440 x 1080 px

Desktop viewing

16:9 (Widescreen)

1920 x 1080 px

Cinematic content

Video File Requirements

Specification

Requirement

File Types

MP4, MOV

Maximum File Size

1 GB

Recommended File Size

Under 512 MB for optimal upload

Frame Rate

30 FPS

Video Codec

H.264 recommended

Audio Codec

AAC, 128 kbps+

Video Duration

Duration Type

Specification

Minimum

No strict minimum

Recommended

5-30 seconds

Optimal Length

60 seconds for engagement

Maximum

Up to 15 minutes

Best practice: Front-load your key message in the first 3 seconds. Most users scroll quickly, so hook attention immediately.

Video Thumbnail Specs

Specification

Requirement

Dimensions

400 x 300 px

Aspect Ratio

4:3 landscape

File Types

JPG, PNG

Maximum File Size

500 KB

Thumbnails display before autoplay and when users have autoplay disabled. Always upload a custom thumbnail rather than relying on auto-generated frames.

Video Ad Text Requirements

Element

Character Limit

Headline (Feed)

150 characters max

Headline (Conversation)

100 characters max

Call-to-Action

Pre-set options available

Carousel Ad Specs

Carousel ads let you showcase multiple images in a swipeable format:

Carousel Structure

Specification

Requirement

Minimum Cards

2

Maximum Cards

6

Card Uniformity

All cards must use same aspect ratio

Carousel Image Specs (per Card)

Specification

Requirement

Dimensions

Same as image ads (1080x1080, 1080x1350, etc.)

File Types

JPG, PNG

Maximum File Size

3 MB per card

Aspect Ratio

Consistent across all cards

Carousel Text Requirements

Element

Character Limit

Notes

Ad Headline

150 characters

Applies to entire carousel

Card Headlines

Optional

Individual card text

Card Descriptions

Optional

Individual card text

Best practice: Use carousel ads to tell a sequential story, showcase product features, or display multiple products. Maintain visual consistency across all cards.

Conversation Ad Specs

Conversation ads appear within comment threads, providing native placement. Learning best reddit conversation ads techniques helps maximize engagement with this format.

Conversation Ad Requirements

Specification

Requirement

Placement

Within comment sections

Headline Limit

100 characters (shorter than feed ads)

Image/Video

Same specs as standard ads

Engagement

Users can upvote, downvote, and comment

Conversation Ad Best Practices

  • Shorter headlines required: 100 characters max (vs. 150 for feed)
  • Native tone: Content should feel like part of the discussion
  • Enable comments strategically: Be prepared to engage with responses
  • Educational content wins: Users in threads expect helpful information

Conversation ads work exceptionally well when your content genuinely adds value to the discussion topic.

Text & Headline Requirements

Across all ad formats, these text specifications apply:

Character Limits Summary

Element

Feed Placement

Conversation Placement

Headline

150 characters

100 characters

Display URL

Auto-generated

Auto-generated

CTA Button

Pre-set options

Pre-set options

Available Call-To-Action Buttons

Reddit offers these CTA options:

  • Learn More
  • Shop Now
  • Sign Up
  • Download
  • Apply Now
  • Contact Us
  • Get Quote
  • Watch More
  • See Menu
  • Book Now
  • Play Now

Headline Writing Tips

  1. Include your primary keyword naturally
  2. Lead with value proposition or hook
  3. Avoid excessive caps or punctuation!!!
  4. Match community tone--corporate speak underperforms
  5. Test multiple headlines (3-5 variants recommended)

What Are the Best Practices for Each Reddit Ad Format?

Image Ads

When planning your image creative, consider these approaches alongside your overall reddit advertising strategy to ensure format specs align with campaign goals.

Do:

  • Use 4:5 portrait for mobile-first campaigns
  • Add text overlay to images (but keep it minimal)
  • Test meme-style creative against polished assets
  • Include your logo subtly

Don't:

  • Use heavy text overlays (reduces performance)
  • Upload blurry or low-resolution images
  • Use generic stock photos without customization
  • Ignore aspect ratio recommendations

Video Ads

Do:

  • Design for sound-off viewing (add captions)
  • Hook viewers in the first 3 seconds
  • Show actual product/service in action
  • Keep optimal length around 60 seconds
  • Use custom thumbnails

Don't:

  • Start with logo animations (users scroll past)
  • Rely on audio for key messaging
  • Upload videos over 512 MB (slower processing)
  • Use horizontal-only for mobile campaigns

Carousel Ads

Do:

  • Tell a story across cards
  • Use first card as the hook
  • Maintain visual consistency
  • Include CTA on final card

Don't:

  • Mix aspect ratios across cards
  • Use unrelated images
  • Skip the narrative opportunity
  • Overload with text per card

Conversation Ads

Do:

  • Match the discussion topic authentically
  • Prepare for user engagement (comments)
  • Use educational/helpful content
  • Keep headlines under 100 characters

Don't:

  • Use aggressive sales language
  • Ignore user comments
  • Place in irrelevant threads
  • Copy/paste feed ad content

How Do Mobile vs. Desktop Affect Reddit Ad Specs?

Understanding device distribution is crucial for creative decisions. Many digital marketing agency reddit teams prioritize mobile optimization given platform usage patterns.

Platform

Usage Share

Primary Format Recommendation

Mobile

70%+

4:5 portrait or 1:1 square

Desktop

~30%

16:9 or 4:3 landscape

Mobile-First Design Tips

  • Assume sound-off viewing
  • Use larger text overlays (readable at small sizes)
  • Keep key content in center safe zone
  • Test thumbnails at mobile preview size
  • Front-load messaging (users scroll quickly)

Quick Reference Cheat Sheet

Copy this table for your creative team:

Image Ads Quick Specs

Dimensions: 1080x1080 (1:1), 1080x1350 (4:5), 1920x1080 (16:9)
File type: JPG, PNG
Max size: 3 MB
Headline: 150 chars (feed), 100 chars (conversation)
Dimensions: Same as image (1080x1080, 1080x1350, etc.)
File type: MP4, MOV
Max size: 1 GB (recommended under 512 MB)
Duration: 5-60 seconds recommended (max 15 min)
Frame rate: 30 FPS
Thumbnail: 400x300 px, JPG/PNG, max 500 KB
Cards: 2-6 per ad
Dimensions: Same as image ads
File type: JPG, PNG
Max size: 3 MB per card
All cards: Same aspect ratio required

Image vs Video Ad Specs Comparison

Frequently Asked Questions

What'S the Best Image Size for Reddit Ads?

For most campaigns, use 1080x1350 pixels (4:5 portrait) for mobile-first reach, or 1080x1080 pixels (1:1 square) for balanced mobile/desktop performance. Since 70%+ of Reddit usage is mobile, 4:5 portrait delivers the largest visual footprint in the feed.

What Video Length Works Best on Reddit?

Reddit allows videos up to 15 minutes, but the optimal length is 60 seconds for engagement. For awareness campaigns, 15-30 seconds works well. Always hook viewers in the first 3 seconds, and design for sound-off viewing with captions.

Can I Use Gifs in Reddit Ads?

Reddit accepts GIF files, but they get converted to static images on upload. If you want animated creative, use MP4 video format instead -- it preserves motion and gives you better quality control.

What'S the Maximum File Size for Reddit Ads?

Image ads: 3 MB maximum. Video ads: 1 GB maximum, though 512 MB is recommended for faster processing. Carousel cards: 3 MB per card. File size can impact upload speed and delivery performance.

Why Is My Reddit Ad Headline Getting Cut Off?

Feed placements allow 150 characters, but conversation placements only allow 100 characters. If you run multi-placement campaigns, keep all headlines under 100 characters to ensure full visibility across every placement type.

How Can I Verify My Ad Meets All Requirements?

Pre-check your dimensions, file sizes, and character counts against the specs in this guide before uploading. Reddit's platform will flag spec violations during upload, but verifying beforehand saves time and avoids rejected creative.

Key Takeaways

  • 4:5 portrait (1080x1350) is the optimal image/video ratio for mobile-dominant Reddit
  • Keep video under 60 seconds with hook in first 3 seconds
  • Headline limits differ by placement: 150 chars (feed) vs. 100 chars (conversation)
  • File size limits: 3 MB images, 1 GB video (512 MB recommended)
  • Always upload custom thumbnails for video ads
  • Test multiple creative variants (3-5 per campaign recommended)

For comprehensive platform guidance beyond creative specs, explore how does reddit advertising work to understand the full campaign setup process. When evaluating channel mix, compare reddit ads vs facebook ads to determine optimal budget allocation. For Facebook-specific specs and pricing, see our Facebook Ads cost guide for 2026.