Open any competitor's Meta ad library and you'll see a format that dominates the grid — maybe 40 static images, a dozen short videos, a handful of carousels. The instinct is to copy the majority. That instinct is wrong. The format a brand runs most is just the format they produce most cheaply. The format that wins is the one that survives longest in the wild. Those are rarely the same thing, and the gap between them is the whole game.
This is a per-brand diagnostic. If you want the definitions — what counts as a static, a UGC video, a carousel, a problem-agitate hook — start with our formats taxonomy post and come back. Here we assume you know the categories. The question on the table is sharper: for this specific brand, which format carries their durable winners?
Why "most run" lies and "longest run" tells the truth
Meta doesn't hand you a performance column. No CTR, no CPC, no ROAS for a competitor's ads — that data lives inside their ad account and nowhere else. Anyone showing you a competitor's exact ROAS invented it.
What you can observe is time. An ad that's been live 90+ days is an ad the brand keeps paying for, day after day, when they could have killed it for free. Nobody bankrolls a loser for three months. Days-running is the performance proxy — not because it's a vanity metric, but because it's a survival metric. The market already ran the test; you're reading the result.
So the move is to stop counting formats and start timing them. Cross the format mix against the run-time distribution and a brand's real strategy surfaces.
The cross-tab that exposes the winner
Here's the shape of the analysis. For one brand, bucket every active ad by format, then look at how long each format's ads actually survive:
| Format | Share of active ads | Median days running | Longest-running ad |
|---|---|---|---|
| Static image | 48% | 21 days | 34 days |
| UGC video | 22% | 96 days | 180+ days |
| Carousel | 18% | 28 days | 41 days |
| Founder/talking-head | 12% | 71 days | 130 days |
Read that table the way a media buyer would. Static images are nearly half the library — and they churn out in three weeks. They're the brand's testing layer: cheap to make, fired off in volume, mostly discarded. The UGC videos are barely a fifth of the output but they're the ones that go the distance. This brand's winning format is UGC video. The static flood is noise around it.
Now swap in a different brand and the table inverts — a founder-story brand might see talking-head ads running 200 days while video flops out in two weeks. That's the entire point: there is no universal "best Meta format." There's only this brand's durable format, dictated by their product, price point, and audience. A $400 mattress and a $19 supplement do not win on the same creative.
Don't read the median — read the distribution
One number per format will mislead you. A format can show a healthy median because of two ancient survivors while everything else dies young. Always pull the spread.
Three patterns to recognize:
- A long right tail — a cluster of ads pushing 100, 150, 200+ days. This is a proven, repeatable winner. The brand has a formula and runs it again and again.
- A flat young distribution — everything clumped under 30 days. Either a format they're still testing, or one that simply doesn't hold for them. Don't copy it yet.
- One lonely outlier — a single 300-day ad and nothing else nearby. That's often a pinned brand-awareness or always-on retargeting ad, not a scalable acquisition winner. Discount it.
The winning format is the one with the fattest tail of survivors, not the highest single number.
Do it by chat instead of by spreadsheet
You don't have to build this table by hand. AdWhispr ingests a brand's entire Meta ad library, snapshots it daily — Meta's API returns no history, so that daily snapshot history is the product — and lets you interrogate it in plain language, either on the web app or inside Claude via the MCP server.
Connect through OAuth at https://adwhispr.com/api/mcp, or run:
npx adwhispr-mcp-server config
Then drive the diagnostic with prompts like these:
- "Add gymshark and break their active ads down by format."
- "For Gymshark, show median and max days-running per format. Which format has the longest survivors?"
- "Show me the days-running distribution for their UGC videos — is it a long tail or a couple of outliers?"
- "List every Gymshark ad over 90 days old and tell me what format and hook each one uses."
- "Compare the winning format for Gymshark vs Alphalete — do they win on the same creative?"
That last comparison (compare_brands under the hood) is where it gets useful: run it across three or four competitors in your category and you'll see whether the whole vertical has converged on one durable format or whether each brand wins differently. Both answers are strategically loaded.
From "what wins" to "why it wins"
Knowing the format is step one. The durable ads also share a hook and tone — that's the reusable pattern. Once you've isolated the surviving format, pull the common thread across those survivors:
- "What hook do Gymshark's longest-running UGC videos open with?"
- "Across their 90+ day ads, what tone and offer structure repeats?"
Now you have a grounded brief instead of a guess: the format that survives, the hook that recurs inside it, and the offer it carries. Feed that into clone_ad and you get an original creative in your brand identity — a generated image for static winners, or a scene-by-scene script and shot list plus a UGC creator brief for video winners — built on the verified survivor, with the source ad cited. You're not copying their pixels; you're inheriting their proven structure.
The one mistake to avoid
Don't confuse volume with conviction. A brand pumping out fifty new statics a week looks aggressive, but a high creative-iteration rate in a format with short run-times means they're still searching — they haven't found their winner in that format. The brand quietly running the same three UGC videos for four months has already found theirs. Survival beats output. Every time you evaluate a competitor's format, ask the durable question first: not what are they making most of, but what have they refused to turn off.
That's the format worth borrowing.
Stop counting a competitor's ads and start timing them — run the format-by-days-running cross-tab in AdWhispr.