Meta Ad Relevance Diagnostics: The 500-Impression Floor Nobody Mentions
Why are my Meta ad relevance diagnostics showing as unavailable?
Most often because the ad has fewer than 500 impressions — Meta does not calculate diagnostics below that threshold. They are also limited to the last 35 days, and unavailable for dynamic creative and for several optimisation goals including reach and impressions.
In short
Meta documents three hard constraints on ad relevance diagnostics that explain nearly every “why is this column empty” question:
- Not available for ads with fewer than 500 impressions.
- Only available for the last 35 days.
- Not available for dynamic creative, or for the ad recall lift, impressions, reach, custom conversions and value optimisation goals.
And one that changes how they should be read: they are not inputs into the ad auction.
The percentile bands, which Meta does publish
For engagement rate ranking, Meta defines the buckets precisely — and “average” is not what most people assume:
| Ranking | Percentile |
|---|---|
| Above average | above the 55th percentile |
| Average | 35th to 55th percentile |
| Below average | bottom 35% of ads |
| Below average | bottom 20% of ads |
| Below average | bottom 10% of ads |
“Average” means the 35th to 55th percentile. An ad sitting at the 40th percentile — below the median of its competitive set — is labelled average. The word is doing less reassuring work than it appears to.
Meta spells out the reading for the lower bands: a ranking of below average (bottom 20%) means “at least 80% of ads competing for the same audience had a higher expected engagement rate”.
Not an auction input
This is the most consequential line in the documentation and the most widely ignored: ad relevance diagnostics “aren’t inputs into the ad auction”.
They are a post-hoc description of how an ad performed against its competitive set, not a score the auction consults. Meta’s guidance is explicit that achieving high rankings “should not be your primary goal, and doesn’t guarantee an increase in results”, and that diagnostics should be used to diagnose underperforming ads — not to tune ads that are already hitting their objective.
An ad delivering your target cost per acquisition with below-average quality ranking is a fine ad. Meta says so in as many words: “sometimes high performing ads have below average ad relevance diagnostics rankings and that’s ok.”
How to read the three together
Meta’s documented principle: reviewing the diagnostics together gives more insight than any one alone, and “it’s more impactful to move a ranking from low to average than it is to move a ranking from average to above average”.
The combinations that carry a clear reading:
| Quality | Engagement | Conversion | Meta’s diagnosis |
|---|---|---|---|
| Avg+ | Avg+ | Below | The ad isn’t producing conversions — fix the call to action or post-click experience |
| Avg+ | Below | Avg+ | The ad isn’t spurring interest — make it more relevant or engaging |
| Below | Avg+ | Avg+ | Perceived as low quality — improve creative assets |
| Below | Avg+ | Below | Meta’s wording: the ad “is click-baity or controversial” |
| Below | Below | Below | Room for improvement across the board — test targeting, creative and goal |
That fourth row is the useful one. Strong perceived engagement with weak quality and weak conversion is the documented signature of a hook that overpromises relative to the product.
The deprecation to know about
Meta records that from June 2024, dynamic creative could no longer be selected when creating ad sets with the sales or app promotion objectives, and recommends the flexible ad format instead. Existing campaigns using it were unaffected at that time. Since diagnostics are unavailable for dynamic creative anyway, accounts migrating to flexible ad format gain a diagnostic surface they did not previously have.
Interpretation boundary
These constraints and bands are Meta’s, retrieved on 2026-09-22, and the article states the 35-day availability and 500-impression floor as current behaviour rather than a guarantee. The percentile definitions describe an ad’s standing against others competing for the same audience — change the audience and the same creative can change band without being edited.
Can software help?
Bach.ai audits your connected Meta account, estimates the revenue impact of what it finds, and proposes specific fixes. It applies a change only after you approve it. Think of it as an automated audit layer that surfaces issues and proposed fixes for your review — not a replacement for your team’s judgment, and creative production is not its core job, though the Pro and Agency plans can generate a limited number of variants.
FAQ
Why are my ad relevance diagnostics unavailable?
Most commonly because the ad has fewer than 500 impressions, which is Meta’s documented floor. They are also limited to the last 35 days and unavailable for dynamic creative and for reach, impressions, ad recall lift, custom conversions and value goals.
What percentile is average on Meta engagement rate ranking?
The 35th to 55th percentile. An ad at the 40th percentile, below the median of its competitive set, is still labelled average — the word is less reassuring than it sounds.
Do ad relevance diagnostics affect the Meta auction?
No. Meta documents plainly that they are not inputs into the ad auction. They describe how an ad performed against its competitive set after the fact, and Meta advises against treating high rankings as a goal.
Which ranking should I fix first?
The lowest one. Meta’s documented guidance is that moving a ranking from low to average is more impactful than moving one from average to above average.
Method and sources
“Most often because the ad has fewer than 500 impressions — Meta does not calculate diagnostics below that threshold.”
Source: Meta Business Help Centre, retrieved 2026-09-22:
- https://www.facebook.com/business/help/403110480493160
- https://www.facebook.com/business/help/2351270371824148
Meta’s documentation changes without notice and these thresholds have moved before — verify anything load-bearing against the current version of the article before you act on it.