Creative ad specs, all in one place.
Everything you need to prepare assets for a Rebel campaign — formats, sizes, file limits and technical requirements by channel.
Display Banners
Accepted sizes (HTML5 & static)
- Mobile Banner — 320×50
- Mobile Banner — 300×50
- Large Mobile Banner — 320×100
- Large Mobile Banner — 300×100
- Leaderboard — 728×90
- Large Leaderboard — 970×90
- Wide Skyscraper — 160×600
- Medium Rectangle — 300×250
- Half-Page — 300×600
- Billboard — 970×250
- Mobile Interstitial (Portrait) — 320×480
- Mobile Interstitial (Landscape) — 480×320
- Tablet Interstitial (Portrait) — 768×1024
- Tablet Interstitial (Landscape) — 1024×768
File requirements
| File types | Static: JPG, PNG · Animated: GIF · HTML5: compressed .zip |
|---|---|
| Max file size | 750 KB (JPG/PNG optimal) · 3.5 MB (GIF) · 4 MB total for HTML5 folders (Chrome limit) |
| Resolution | Min 72 ppi — 144 ppi recommended |
| Animation | Up to :15 seconds · max 3 loops |
| SSL | Required (https) for all assets and tags |
| 3rd-party tags | Iframe; JavaScript |
| Click behavior | Click URLs open in a new tab · "Sponsored by" field max 25 characters |
| Not supported | 1:1 ratio placements |
Native
Image & file
| File format | JPG, PNG |
|---|---|
| Optimal file size | 750 KB |
| Resolution | High resolution — min 72 ppi, 144 ppi recommended |
| Image dimensions | All sizes recommended: 1200×627 · 800×600 · 600×600 — no text overlay on the image |
| Tags | Not supported — direct upload only |
| Destination URL | The image is clickable and leads to the article/post |
Text & branding
| Headline | Recommended under 30 characters · max 55 · min 5 (including spaces) |
|---|---|
| Body | Max 120 characters · min 5 (including spaces) |
| Brand logo | Recommended 300×300 px, appears on a white background — preferably PNG |
| Brand name | Max 35 characters · ≤25 recommended (may truncate past 25) |
Placements vary, so not every element is guaranteed to render — the headline, image, URL and "Sponsored by" field always appear; body text and brand logo can vary by publisher. If body text is essential to your creative, tell your Rebel team and we'll restrict delivery to native placements that always display it.
Video & Connected TV
Online video & in-banner video
| Aspect ratio | 16:9 widescreen — Full HD 1920×1080 |
|---|---|
| Resolution | Min 400×300 · Max 1920×1080 |
| File size | Online video: max 150 MB · In-banner video: max 3.5 MB |
| Duration | :15 to :30 seconds |
| File types | .MP4, .MOV |
| In-banner extras | Logo + headline (55 chars) + body text (120 chars) + CTA (25 chars) |
Standard CTV
| Resolution | 1920×1080 |
|---|---|
| File size | Max 1 GB |
| Duration | 15, 30 or 60 seconds |
| File type | .MP4 |
Premium CTV (Disney/Hulu, NBCU/Peacock, Paramount, WBD)
Premium publishers require transcoded assets to scale effectively. Raw MP4 uploads must meet:
| Format / codec | MP4 preferred · Video: H.264 · Audio: AAC |
|---|---|
| Video bitrate | 15–30 Mbps · Constant Bit Rate (CBR) preferred |
| Frame rate | Match the publisher — Disney+/Hulu: 23.98/24/25/29.97/30 · NBCU/Peacock: 23.98/25/29.97 · Paramount & WBD: 23.98/24/25/29.97/30 |
| Resolution | Minimum 1920×1080 |
| Audio | 48 kHz sample rate · 192 kbps+ (320 preferred) · loudness −23 LKFS ± 2 LU |
| Quality rules | No blended, duplicated or deinterlaced frames · no telecine/3:2 pull-down · VAST tags allowed but not transcoded (must meet publisher specs) |
Streaming Audio
Audio asset
| File formats | MP3, M4A, OGA, WAV, FLAC, AAC — include MP3 (or M4A) + OGA in your tag |
|---|---|
| Framework | VAST 2.0+ |
| File size | Under 500 MB — smaller is better |
| Bitrate | 128–160 Kbps recommended · 320 max |
| Duration | :15 or :30 recommended · Spotify max :30 (no cannabis, CBD or religion content) |
| Skippability | Audio is generally non-skippable (podcast inventory excepted) |
Companion banner
| Sizes | 300×250 (mandatory) · 320×50 · 728×90 · 600×600 (Spotify only) |
|---|---|
| Format | PNG or JPG · max 750 KB |
| Resolution | Min 72 ppi — 144 ppi recommended |
Digital Out-of-Home (DOOH)
Key rules
| Exact sizing | Creatives must exactly match target inventory dimensions — DOOH assets are never up- or down-scaled |
|---|---|
| File size | Static (JPG/PNG): max 10 MB · Video (MP4): max 50 MB — limits vary by media owner |
| Audio | Exclude audio unless essential to the message |
Common screen dimensions
- 300×250 · 728×90 · 160×600 (adjacent placements)
- 300×600 — full screen
- 1080×1920 — full screen (portrait)
- 1920×1080 — full screen (landscape)
- 1920×960 — full screen
Images: .jpg/.png (sRGB) · HTML5/JavaScript supported · specs vary by venue type and media owner.
Glossary
HTML5
Creative packaged in a .zip containing an index file (HTML) plus supporting scripts, images or style files.
VAST
"Video Ad Serving Template" — a script that tells video players which ad to play, how it should appear, its length, and whether it can be skipped.
VPAID
"Video Player Ad-serving Interface Definition" — a script instructing a video player on what ad to play, its length, and when and where to surface it.
Bitrate
How much data is transmitted per second (Kbps/Mbps). Higher bitrate generally means higher quality and larger files.
Aspect Ratio
Ad units that maintain their proportions and adjust to screen size for responsive placements.
Initial vs. Polite Load
The initial load is the max file weight allowed at page load (kept light for speed); heavier assets "politely" load after the page finishes.
Backup Image
A static image served with rich/HTML5 creative in case the user’s browser can’t display the primary asset.
Web Font
Fonts downloaded by the browser when the page loads, rather than installed on the user’s device.
Specifications vary by publisher, platform and media owner and change over time. Final specs are confirmed per campaign by your Rebel team — when in doubt, just ask us.
Questions about your creative?
Send us what you have — we'll confirm the specs and get your campaign moving.
Paid Social
Facebook & Instagram
TikTok (in-feed)