FLUX 3 Max YouTube Ads: In-Stream, Bumper and Shorts

To make YouTube ads with FLUX 3 Max, match each format to a clip length: 5 seconds for a bumper, 15 or 20 seconds for skippable in-stream, and 10 to 20 seconds of 9:16 for Shorts. Render finals at 1080p, the resolution Google recommends for skippable ads. At 29 credits per second, a 15 second spot costs 435 credits.

This guide covers the production side of FLUX 3 Max YouTube ads: which format takes which clip, the aspect ratios Google lists, how to build a skippable spot that survives the skip button, copy-paste prompts, and what a full campaign set costs in credits. Campaign settings and bidding belong in Google Ads; everything here is about the video you upload.

Which YouTube ad formats can FLUX 3 Max cover?

FLUX 3 Max generates one continuous shot of 5, 8, 10, 12, 15 or 20 seconds, with audio produced in the same pass. That maps cleanly onto the short YouTube formats:

The figures come from Google's video ads specs and format requirements and its page on skippable in-stream ads. The same skippable page recommends 1080p, with 720p as the minimum for HD, which is why every final in this guide is rendered at 1080p.

Longer formats are still possible. Google's skippable page recommends two to three minutes for consideration goals. One FLUX 3 Max generation tops out at 20 seconds, so a cut that long means joining several clips in the editor, each one written as its own scene.

Which aspect ratios should FLUX 3 Max YouTube ads use?

Google's spec page lists three ratios for in-video ads: 16:9 at 1920 x 1080, 9:16 at 1080 x 1920 and 1:1 at 1080 x 1080. FLUX 3 Max renders all three at 1080p.

21:9 is the tempting one, because it reads as cinema. For paid placements, stay inside the three ratios Google lists. For an organic upload, YouTube's player resizes itself to fit the video, so a 21:9 brand film on your channel is a reasonable place for that look. The FLUX 3 Max cinematic brand video guide covers how to shoot for it.

Generate each ratio as its own clip rather than cropping one master. A 16:9 shot cropped to 9:16 loses most of its frame, and the subject rarely lands where a vertical screen wants it.

How do you build a skippable in-stream ad that survives the skip?

The first 5 seconds carry the whole ad, because that is when the skip button appears. Google's ABCDs of effective video ads give four principles that translate directly into prompt decisions:

A practical structure is a 5 second hook clip followed by a 10 second body clip, joined in the editor. It costs exactly the same as a single 15 second generation (145 plus 290 credits, against 435), and it lets you swap hooks without regenerating the body. Three hooks and one body give you three 15 second variants for 725 credits at 1080p.

Write each prompt as one paragraph: subject and action, then camera, then light and look, then sound. Here is a hook clip, text to video, 16:9, 5 seconds:

A runner in her forties sprints up the last steps of a steep stone staircase at dawn and stops at the top, breathing hard. Low angle, fast push-in to a medium shot. Cold blue light with the first orange sun on her face, crisp high-contrast grade. Footsteps slapping on stone, heavy breathing, a single deep drum hit as she stops, no voice.

And the body clip, image to video, 16:9, 10 seconds. The start frame is your product photo of the shoe on wet asphalt, so the prompt covers motion and sound only:

A drop of water lands on the shoe and beads off the upper as the camera makes a slow half-orbit around it. A runner's foot steps into frame beside it. A woman's voice says, "Strideline. Try them on the hill you keep avoiding." Rain on asphalt, a distant car passing, a low pulsing synth beat.

The spoken line names the brand and the next step in nine words, well inside the two to three words per second a 10 second clip allows. Listen to the brand name on the 720p draft: generated speech must be checked before a clip goes live, and an unusual name is the first thing to verify.

If you would rather run one unbroken shot, a single 15 or 20 second generation works too. Keep it to one idea: twenty seconds is room for one beat done well, not a montage.

How do you make a YouTube Shorts ad with FLUX 3 Max?

Shorts ads are vertical, and Google's Shorts ads asset specs recommend using sound, music, voiceover or both. FLUX 3 Max always generates audio, so the clip arrives with voice, ambience and music from the same generation.

Two Shorts-specific details. The right-hand side of the Shorts screen carries the like, comment and share buttons, so keep the product centred or left of centre. And the feed around the ad is creator video, so a person, a phone-height camera and one line will sit more naturally there than a polished commercial.

Shorts ad, text to video, 9:16, 15 seconds:

A man in his twenties sits on a park bench, holds a running shoe up to the camera, then presses his thumb into the sole and lets it spring back. Handheld selfie angle, eye level, the shoe kept in the centre of the frame. Soft late-afternoon light, natural grade. He says, "Light, springy, and they still grip in the rain. That's why I switched." Park ambience, birds, a dog barking in the distance, no music.

Text to video invents the shoe, so use it for concept tests. For the version you run, attach a photo of someone holding your actual product as the start frame and keep the motion and sound sentences. If a line reads as a real customer's experience, it needs to be one, or disclosed; the FTC disclosure guide for AI UGC ads covers where that line sits. For more vertical formats, FLUX 3 Max TikTok ads uses the same 9:16 approach.

What does a FLUX 3 Max YouTube ads campaign cost?

FLUX 3 Max costs 17 credits per second at 720p and 29 credits per second at 1080p, the same for text to video and image to video. Cost per asset:

A launch campaign set with three in-stream variants (three hooks, one body), two bumpers and two Shorts ads costs 1,885 credits at 1080p. Drafting all of it at 720p first adds 1,105, for 2,990 in total. That fits inside the Pro plan's 5,600 monthly credits with room for retakes. On the Starter plan's 1,400 monthly credits, render the three in-stream variants and one Shorts ad at 1080p for 1,160 credits.

One credit is one cent of generation cost, so a finished 15 second spot is $4.35 of plan credit. Set that against a shoot day for a single YouTube spot. Every duration is worked out in the FLUX 3 Max pricing guide, and current plans are on the pricing page.

What should you check before a YouTube ad goes live?

Watch every clip with sound on, at full screen, and run this list:

• The first 5 seconds stand alone. If a viewer skips at 5 seconds, did they still see the brand or the product?
• The brand appears early. Add the logo in the opening seconds after export, and confirm the spoken brand name is pronounced correctly.
• The line is complete and the lip sync holds. Generated speech must be watched before it goes live.
• No garbled text in frame. Small text and exact logos inside generated frames are unreliable on every video model, so the CTA, offer and logo go on after export, never in the prompt.
• The ratio matches the slot. 16:9 for in-stream and bumpers, 9:16 for Shorts, and nothing outside Google's three listed ratios in an ad slot.
• The sound works for the format. If you want a different music bed, replace the track with your own audio; FLUX 3 Max always generates audio.

If you are weighing other models for the same job, the Kling guide to YouTube ads covers the image to video route with a silent model, where all sound is added afterwards.

Frequently Asked Questions

How long should a YouTube ad be?

It depends on the format and goal. Google recommends 15 to 20 seconds for skippable in-stream ads aimed at awareness or action, 6 seconds for bumpers, and 10 to 30 seconds for action-oriented Shorts ads. FLUX 3 Max covers all of these in a single clip of up to 20 seconds.

What is the best aspect ratio for YouTube ads?

Use 16:9 for in-stream, bumper and in-feed ads, 9:16 for Shorts, and 1:1 for square placements. Those are the three ratios Google lists for in-video ads, and FLUX 3 Max renders all three at 1080p.

What resolution should YouTube ads be?

Google recommends 1080p for skippable in-stream ads, with 720p as the minimum for HD. Draft FLUX 3 Max clips at 720p for review, then render the version you upload at 1080p.

How much does a YouTube ad made with FLUX 3 Max cost?

At the standard rate, a 5 second bumper is 145 credits at 1080p, a 15 second skippable spot is 435 credits and a 20 second spot is 580 credits. A 720p draft of the 15 second spot costs 255 credits.

Can FLUX 3 Max make a bumper ad?

Yes. Bumpers are non-skippable ads of up to 6 seconds, and FLUX 3 Max offers a 5 second duration. Write one action and one sound cue, render at 1080p for 145 credits, and add the logo after export.

Do YouTube Shorts ads need sound?

Google's Shorts ad guidance recommends using sound, whether music, voiceover or both. FLUX 3 Max generates audio with every clip, including spoken lines you write into the prompt, so a Shorts ad arrives with sound from one generation.