CTV Specs: The Video Ad Requirements You Need Before You Upload

What CTV specs actually cover

Connected TV (CTV) means ads served to a television through an internet-connected device or app: a smart TV, a streaming stick, a games console. Because the screen is a living-room TV, the creative rules look more like broadcast than like a social video. A file that works on a phone feed can be rejected, letterboxed or muted when it reaches a streaming platform.

When people search for CTV specs they usually mean five things: the picture (size and aspect ratio), the length, the file and codec, the audio, and the way the ad is delivered to the player (a tag or a file upload). A sixth, less discussed item is the policy layer: clickable elements, end cards and calls to action are treated very differently on a TV than on a screen you can tap.

The pages that rank for this term, including the IAB Tech Lab's digital video and CTV guidelines and the creative upload guides from large buying platforms, all describe the same core idea: there is a shared industry baseline, and then every seller layers its own limits on top. That is why a single master list is never enough, and why the checklist later in this guide matters more than any one number.

The common baseline, spec by spec

These are the values most CTV sellers accept or ask for. Treat them as a starting point for producing your master file, not as a promise that every platform will take it.

• Aspect ratio and size: 16:9 widescreen, delivered at 1920x1080 (full HD). Some sellers accept 4K, and some accept 1280x720, but 1920x1080 is the safest master.
• Length: 15 and 30 seconds are the standard slots. Shorter 6 and 10 second cuts and longer 60 second cuts exist on some inventory, but plan 15s and 30s first and check the seller for anything else.
• Container and codec: an MP4 file (some accept MOV) with H.264 video is the most widely supported combination.
• Frame rate: keep the frame rate your footage was shot in and avoid conversions. Common broadcast rates of 24, 25 and 30 frames per second are generally fine; check whether a seller asks for a constant frame rate.
• Audio: stereo AAC, usually at 48 kHz. Many sellers also ask for a loudness target in line with broadcast practice (often described as about -24 LKFS under the ATSC A/85 recommendation), so the ad does not play louder than the show around it.
• Bitrate: sellers differ here, and the guidance is usually a range rather than a single value. Export at a high quality, then check the range on the spec sheet.
• Ad delivery: many platforms accept either a hosted video file or a VAST tag, the IAB's standard template for serving video ads to a player. If you use a third-party ad server, confirm which VAST version the seller supports.
• File size: there is almost always a maximum. Large masters may need a second, compressed export.

One practical rule: build one clean master at the highest spec you were given, and make smaller exports from that master. Going the other way, upscaling a compressed file, is where banding and blur come from.

Where the platforms differ, and why that matters

The baseline is shared. The exceptions are not, and they are the reason uploads get bounced. The differences usually fall into four groups.

• Length rules. Some inventory only sells 15s and 30s. Premium live sports and long-form programming may allow longer or non-standard lengths.
• Bitrate and file-size ceilings. These vary by seller, so a file that passes one platform's checker can fail another's.
• Loudness checks. Some sellers measure it automatically and reject outside a tolerance. Others only publish a recommendation.
• Interactive and end-card rules. Some CTV formats allow a QR code or a remote-control interaction. Others forbid on-screen URLs or ask that any QR code stay on screen for a minimum time. Read the policy page as carefully as the technical page.

This is also where Amazon's own streaming inventory sits. Amazon DSP can reach streaming TV supply on Amazon-owned surfaces and on third-party publishers, and each supply source carries the rules of the seller that owns it. When we run streaming for brands, we treat the spec sheet of the specific supply source as the authority, not a generic CTV checklist.

The takeaway: do not memorize one set of numbers. Keep a one-page record of the limits for each seller you buy from, and update it when they publish changes.

What the creative needs beyond the file

Passing the technical check only gets the ad approved. It does not make it work on a television. A few creative choices matter more on a TV than anywhere else.

• Safe zones. Televisions and apps can crop the edges of the picture or overlay their own interface. Keep logos, prices and legal lines well inside the frame rather than hard against an edge.
• Sound on, but not relied on. A TV is usually sound-on, which is a real advantage over social. Still, subtitles or on-screen text for the key message help in a shared room.
• Big, short text. Viewers are several feet from the screen. Small print and long URLs are unreadable at that distance.
• A clear first 3 seconds. Name the brand early. In a 15 second slot there is no time for a slow build.
• An end card that tells the viewer what to do next. A TV screen cannot be tapped, so the next step is usually a search, a QR code where permitted, or a later retargeted ad. Say plainly what you want them to look up.
• One idea per ad. The 15 and 30 second lengths are enough for one message, not three.

Shoppers who see a streaming ad often act later, on another screen. That is why a CTV ad for an Amazon seller should ask the viewer to do something simple, like search for the product, and why the measurement should look beyond last-click clicks, which a TV ad cannot generate in the first place.

A pre-flight checklist before you upload

Run this list for every platform, every time. It takes about five minutes and avoids the most common rejections.

• Download the current spec sheet from the seller, not an old PDF, and note the date you read it.
• Confirm the exact lengths the line item allows, and that your file runs to exactly that length (a 30 second ad that runs 30.5 seconds can be rejected).
• Check resolution, aspect ratio and frame rate against the sheet.
• Check container, video codec and audio codec.
• Measure loudness with a meter, not by ear, and compare it with the stated target.
• Check the file size and bitrate against the stated limits.
• Look at the whole frame on a real TV or a TV-sized monitor, with the safe zones in mind.
• If you use a VAST tag, test it in the seller's tag tester and confirm the VAST version.
• Read the policy page for end cards, QR codes and claims, and confirm that any on-screen offer is allowed.
• Upload early. Approval can take days on some platforms, and a rejected ad on launch day is a lost day.

Tip: keep the approved file, the spec sheet you used and the approval message together. If anything goes wrong later, you will know what was submitted and when.

A worked example: one master, three exports

For example, say you are launching a streaming campaign for a product brand and you need a 30 second hero ad and a 15 second cut.

• Edit one 30 second master at 1920x1080, 16:9, with stereo audio, leaving safe margins for text.
• Cut a 15 second version from the strongest half of the story, rather than speeding the 30 up.
• Export each as MP4 with H.264 video and AAC audio, then check both against the loudness target you have been given.
• If a platform has a lower file-size limit, make a compressed copy of that export for that platform only, and leave the master untouched.

That gives you two deliverables and one compressed variant, and every one of them traces back to a single clean master. When a platform changes its spec, you re-export from the master instead of re-editing.

Where reMKTR fits

reMKTR (remktr.com) runs Amazon DSP as a service, including streaming TV. We buy on our own advertiser accounts rather than reselling access, and we check each supply source's creative rules before a campaign launches so approvals do not hold up a start date. reMKTR is part of the Full Circle group, with 100+ brands managed and $500M+ in Amazon revenue managed.

If you are a single seller with one ad and one platform, the checklist above is all you need and you do not need a service for it. If you are planning streaming across several supply sources, each with its own limits, a managed team saves the repeated exports and the approval back-and-forth.