Use case
Change one line, hold everything else. Otherwise nothing is learned.
Most hook tests change the opening, the pacing and the caption style together, then declare a winner. That result is unreadable. Here is why a three variable test teaches nothing, how many openings the arithmetic actually demands, which number judges a hook, and how one body holds identical across sixteen of them.
- Creatives that carry spend, per Motion
- 5-8%
- Cost of one more opening
- 110 CR
- What has to stay identical
- 1 body
A hook test with three variables is not a test, it is a preference
The standard version of this goes wrong quietly.
Four ads go live. They have different first lines.
They were also cut on different days, so the pacing drifted and the caption pack changed.
One wins. The team concludes the hook worked, and writes three more like it.
None of them repeat the result, because whatever caused the win was not isolated.
The requirement is boring and non-negotiable.
Same body, same pace, same caption treatment, same length.
One variable, which is the first sentence.
This is difficult in a timeline editor, because rebuilding the same body four times introduces small differences you cannot see.
It is straightforward when the cut is compiled from a transcript. The body is the same source and the opening is a deletion.
- Same body, same pace, same captions, same length, one changed line
- A win you cannot attribute is a win you cannot repeat
- Small unintended differences are the usual reason a hook result does not replicate
The arithmetic decides how many openings you need, and it is not four
Published benchmarks put the share of ad creatives that become winners at roughly 5 to 8 percent.
That comes from Motion's analysis of 550,000+ Meta ads. One in thirteen to one in twenty.
So a test with four openings has a decent chance of containing no winner at all.
The correct conclusion from that test is nothing rather than the least bad one.
Teams almost never draw that conclusion.
They pick the top of four and scale it.
That is how an account ends up spending behind a creative that was merely the tallest of four short ones.
Twelve to twenty openings changes the shape of the result.
It is enough that a real winner is likely to be in the set, and enough that the gap between first and second means something.
That number is only reachable if one more opening is cheap, which is the entire argument for doing this differently.
Sixteen openings, at the published rate
One or two carry. A test of four is likely to contain none, and the winner declared from it is a ranking artefact.
This is the whole editor
Highlight a phrase and a clip lands on those exact words. No timeline, no keyframes, no layers.
Measure the hold, not the click, because the hook only controls the first seconds
A hook is responsible for whether somebody is still watching at three seconds.
It is not responsible for the purchase.
Judging it on cost per acquisition mixes two different jobs.
So the primary number for a hook test is early retention.
Whatever your platform calls it, the share still watching after the first few seconds is the signal you are testing.
Then check that the winner did not simply attract the wrong people.
A hook can hold attention and deliver an audience that never converts.
That is worth catching before you scale it.
Two numbers, in order. Did it hold, and did the held audience behave.
Write the kill rule down before launch, or the ad with an advocate in the room survives longer than the ad with the best hold rate.
One body, sixteen openings, about 1,760 credits
Film the body once, up to three minutes.
Upload it and Cutroom transcribes the read, drafts the cut, places b-roll against your words and returns a finished 9:16 MP4 with captions burned in.
For each variant, change the first line and leave everything else alone.
Delete the current opening and the cut rebuilds around what is left.
The pace and the caption pack come back identical, because they were never placed by hand.
That is the property the whole method depends on, and it is what a timeline cannot give you.
A finished thirty second ad is about 110 credits: 100 for the batch, 10 to render.
Sixteen openings is roughly 1,760 credits, inside one month of Premium at $79.99 for 5,000 credits.
Basic is $39.99 for 2,500 credits, roughly 22 finished ads, which covers a sixteen-opening test with room to replace the losers.
The trial is 7 days and 300 credits with no card, which is two openings.
Openings you can afford per month
- Trial, 300 credits2 openings
- Basic, $39.9922 openings
- Premium, $79.9945 openings
- Each $15 top-up9 more
Film the body once, and the flat facts that keep the test clean
Each project is built from one uploaded take.
So a body filmed twice is two different performances and the test is contaminated again.
Film the body once and reuse that same source for every variant.
If you refilm, treat it as a new test rather than as more data for the old one.
The tool makes the creative. The measurement happens in your ads manager, and the discipline comes from you.
Exports are 9:16 MP4 only and source takes cap at three minutes.
There is no timeline, no keyframes and no layers, which is precisely why the untouched variables stay untouched.
Your own footage sits in the workspace library and can be held constant across every variant too.
Somebody has to be on camera, because the transcript is the interface and there is no read without one.
Questions people ask
- How many hooks should one test contain?
- Twelve to twenty. At a 5 to 8 percent winner rate, a set of four is likely to contain none, and the ad you pick from it is the tallest of four short ones.
- What metric judges a hook?
- Early retention first, then whether the held audience converted. Cost per acquisition alone mixes the hook's job with the rest of the ad's job.
- Can I refilm the body between variants?
- You can, but it breaks the test. Two takes are two performances. Use one source take for the whole set and treat a refilm as a new test.
- Who should not run tests this way?
- Anyone whose creative is not talking-head video. For spoken vertical ads, this is the only route where sixteen openings share one genuinely identical body.
One body, sixteen first lines, every other variable held identical by the compiler rather than by hand. That is a readable result, and a timeline cannot produce one.