App Store keyword popularity estimator

How the estimate works

Apple's search box suggests phrases as you type, and it lists them roughly by popularity: in our study, of two suggested phrases that both sit on Apple's own popularity chart, the one listed higher was the more popular in 85% of 4,807 pairs. A phrase people search often appears after two or three letters, near the top. A rare one appears late, low, or only once the whole phrase is typed.

The tool types the phrase the way VisualASO does: three letters, each whole word, a word plus the next letter, and the full phrase, stopping at the first prefix that offers it. It then reads the ratings of the top ten apps for the phrase from Apple's search API. A linear model, fitted on 1,251 phrase-country cells and tested on a held-out quarter, turns those readings into a number on Apple's 1–100 scale.

Its error, printed

• Against Apple's own popularity charts (held out, 129 cells): Spearman 0.68, mean error 11.7 points. A constant guess has a mean error of 11.4 on those cells, so the value of the estimate is in ordering phrases, not in the exact number.
• Below Apple's charts, against Astro's readings: Spearman 0.62, mean error 14.0 points.
• In the deep tail (popularity 6–20) no model we built could measure demand. The tool says “Low” there.
• By country: United States 0.73, United Kingdom 0.74, Germany 0.77, Spain 0.62, Sweden 0.56 (Sweden from 12 cells).

Method, data and limits: Can Apple's search suggestions measure demand? It is not search volume, and it is labelled so everywhere it appears.

Questions

Is this App Store search volume?

No. Apple publishes no search counts. This is an estimate on Apple's 1–100 popularity scale, made from how early and how high Apple's search box suggests the phrase, plus the ratings of the apps that rank for it.

How accurate is it?

On held-out phrases from Apple's own popularity charts it ordered phrases with a Spearman correlation of 0.68 and missed by about 12 points on average. It sorts phrases better than it sizes them, and it cannot measure the deep tail; there it says “Low” instead of a number.

Why does it show a question mark?

When Apple's search box never offers the phrase, not even inside a longer one, suggestions cannot see its demand. That is not proof of zero searches, so the tool shows “?” instead of 0.

How many lookups can I run?

Each phrase takes a few lookups per country. The tool keeps answers for days and limits how fast it asks Apple, so a busy hour can make it wait. You can run a few dozen phrases a day.

Where can I get Apple's own popularity numbers?

Apple shows popularity to Apple Ads accounts. VisualASO reads it for your phrases when you sign in to your own Apple Ads account, beside this estimate, each labelled with its source.