Answer Radar
Reading the Appearance Rate Metric
Appearance rate is the metric that exists before any other. For Google AI Overviews it asks: when we ran this prompt, did an answer appear at all? Every other visibility metric is computed over the answers that did.
Quick Answer
Appearance rate is the share of a segment's samples in which the engine showed an answer at all: shown divided by shown plus absent. Provider errors are left out of both sides. It sits in every segment's disclosure.
- Only Google AI Overviews produces absent samples today. The assistants answer every query, so their appearance rate is 1.
- A published trigger rate is a share of someone else's query set, not a benchmark for yours.
On this page
The definition and its denominator
"The share of samples in which the engine showed an answer at all: samples with an answer (shown) divided by shown plus samples where the engine showed none (absent). Provider errors are excluded from both sides, because a failed request says nothing about whether an answer would have appeared. For Google AI Overviews an absent sample means Google showed no AI Overview for that prompt. Reported in every segment's disclosure, so it is present even when no other metric is."
Both terms are samples of your own prompts in one segment. A rate of 0.4 over ten samples means four of ten prompts produced an Overview in the window. The disclosure carries shown_samples, absent_samples and error_samples beside the rate, so 4 of 10 is never confused with 40 of 100.
Absent is a grade, not a gap. A sample where Google showed no Overview is graded absent (grader version sample-quality-v2), counted in excluded_by_grade, and left out of every other metric. There was no answer to measure your brand in.
Why errors sit on neither side
A provider error is a failed request: a timeout, a blocked fetch, a malformed response. It says nothing about whether Google would have shown an Overview. Counted as absent it would drag the rate down for reasons unrelated to the engine; counted as shown it would invent an answer nobody saw. So errors are graded error, reported as error_samples, and left out of the fraction.
If every sample in a segment errored, nothing could have appeared, and appearance_rate is null rather than 0. A null means the instrument failed; a 0 means the engine chose not to answer. The disclosure keeps the two apart.
One segment, one country
Appearance rate is computed per segment: engine, model, tool version, geography and language, never pooled. For AI Overviews geography matters more than for any other engine. Google's own availability page, read on 6 September 2026, lists no AI Overviews in China, Iran, Cuba or North Korea; runs in those geographies record blocked samples, and France, live since July 2026, is measured like any other country. Where they are served, appearance differs by country: a United States segment and a Germany segment are two rates.
Phrasing moves it too, which is why the prompt set stays frozen between runs. In single checks on 2026-09-06, "best CRM for small business" showed an Overview, while "What are the best CRM tools for a small business in 2026?" and "how to choose a CRM for a small business" did not. One dated observation, not a rule, and the reason the metric is a rate over many samples rather than a yes or no.
Appearance before presence
Presence rate, recommendation rate and the other visibility metrics are computed only over shown samples. Appearance rate says how many samples that was. A segment with appearance 0.3 and presence 0.5 reads: Google answered three of ten prompts and named you in half of those three.
This is what usable false means for an AI Overviews segment. No Overview in the window means no shown samples, nothing admissible, and no presence or recommendation to compute. Appearance lives in the disclosure rather than the metric set, so it is still reported, and appearance 0 here is a real finding: Google is not answering these prompts with an Overview.
Where you see it
In the app it is the Overview appearance line on the project overview, reading N of M searches, drawn only when the project has Google AI Overviews samples. In the connector it is the appearance block in every segment's disclosure in answer_metrics_get and answer_trends_get, with its sample counts and the definition. In the weekly brief a movement on it is labelled Overview appearance.
Reading a change week to week
Appearance is Google's decision, not yours. A move from 0.4 to 0.6 means Google showed an Overview for more of your prompts than last week in that segment; it does not mean your content did anything. Google changes how often it triggers Overviews, and published measurements disagree about the level: a study of 146 million SERPs put it at 20.5% of keywords; a later roundup put Similarweb at about 43% and Semrush at about 48% of queries. Each measures a different query set, date and country. None is a share of your prompt set.
A poster in r/SEO, in a thread on tracking citations in AI Overviews, put it as: "Run the exact same query 15-20 times and log how often you actually show up." A poster in r/aeo, on a small ranking versus citation experiment, warned that "a single check is a snapshot, not a stable value." Read the rate as a trend on one segment with matching version stamps, and treat a week's step as a hypothesis about Google, not a verdict on your pages.
FAQ
Why is there no appearance rate line for ChatGPT or Perplexity?
Those engines answer every query, so appearance is always 1 and tells you nothing. The connector still reports the block; the app draws the line only when Google AI Overviews samples exist.
My AI Overviews segment says usable false and appearance 0. Is that a bug?
No. No Overview appeared for any of your prompts in that segment and window, so there was nothing to be present in. If it shows null instead, every sample errored; rerun.
Can I compare my appearance rate with percentages from industry studies?
No. Those figures are the share of a vendor's keyword database or tracked panel that triggered an Overview, on their dates and in their countries. Yours is the share of your own prompts in one segment. Compare it only with itself across runs on a matching segment and versions.
Related help pages
Answer Radar
Reading the Visibility Metrics
What presence rate, recommendation rate, share of voice, sentiment mix and citation share mean, which samples count, and why a segment can report no number.
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Track and Win Google AI Overviews With Answer Radar
How Answer Radar measures Google AI Overviews: what an absent Overview means, where the appearance rate shows up, and how to turn a lost Overview into a fix.
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Segments and Topics: How Results Are Grouped
Why every metric is reported per segment and never averaged across engines, what the five axes are, what the instrument token is, and how topics group prompts.