App Store Keyword Difficulty: How to Tell What You Can Win
Every ASO tool sells you a difficulty score, and no two agree. That is not a bug in the tools, none of them can see the algorithm, so each is a different guess. Here is what actually determines whether a shelf is reachable, and how to check it yourself in about two minutes.
Why difficulty scores disagree
Neither Apple nor Google publishes ranking difficulty. Every score you see is a model built from observable proxies, usually some combination of how many apps target the term, how strong the incumbents look, and how much search demand exists.
Different tools weight those proxies differently, so the same keyword can score 34 in one and 61 in another. Neither is wrong; they are answering slightly different questions.
The practical response is not to find the "correct" tool. It is to stop treating difficulty as a number and start treating it as three separate questions.
The three checks that matter
- Is there demand? Apple publishes a search popularity score from 5 to 100 through the Search Ads API, the only official demand figure either store provides. Below roughly 10, almost nobody searches the term and ranking first would win you nothing.
- Are the incumbents beatable? Open the search result and look at the top ten. Count how many have fewer than about a thousand ratings. If two or three do, the shelf has room. If every one is a household name, it does not.
- Are you plausibly relevant? The stores will not rank a note-taking app for "photo editor" however you write your metadata. Relevance is judged from your whole listing, your category and who installs you.
A keyword is worth a character only when all three are true. Any single one being true is what makes people waste months.
Reading a shelf in two minutes
Search the term in the actual store, on an actual device, in the storefront you care about. Then look for:
- Rating counts in the top ten. The single best proxy for entrenchment. Thousands versus hundreds tells you most of what you need.
- Whether the term appears in their names. If the top apps all carry the exact phrase in their titles, they are deliberately targeting it and you are entering a contest. If they rank without it, the store is inferring relevance and there is room to be explicit.
- How many results feel off-topic. A shelf padded with loosely related apps is a shelf the store is struggling to fill, which is an opportunity.
- Whether ads run on it. A term with several advertisers has commercial value that someone has already verified.
Relevance is the invisible gate
The factor tools cannot score is whether the store believes you belong on the shelf at all. It is inferred from your category, your other metadata and, most powerfully, the behaviour of people who find you through that term.
This produces a counter-intuitive effect worth understanding: ranking briefly for a term you are not relevant to makes things worse. People tap, do not install or install and immediately uninstall, and the store learns you do not belong there. You end up harder to rank for it than before you tried.
The corollary is that keyword expansion works outward from what you genuinely are, not toward whatever has the most search volume.
Building a keyword portfolio
A workable split for a single app, roughly twenty to thirty tracked terms:
| Type | Share | Why |
|---|---|---|
| Brand terms | 10% | You should own them, and they are how you spot someone bidding against you |
| Core category terms | 30% | What you obviously are. Winnable within months. |
| Long-tail specific phrases | 45% | Where a small app actually wins. Lower demand, far higher conversion. |
| Reach terms | 15% | Currently unwinnable, tracked so you can see if that changes |
The mistake almost everyone makes is inverting this: most of the portfolio in head terms, almost nothing in the long tail, and then a year of no movement.
Frequently asked questions
What is a good keyword difficulty score?
There is no universal scale, because every score is a different tool's model of an algorithm nobody can see. Two tools scoring the same term 34 and 61 are both defensible.
Judge demand, incumbent strength and your own relevance separately instead of trusting one composite number.
How do I check keyword difficulty for free?
Search the term in the store itself and look at the rating counts of the top ten apps. If two or three have under about a thousand ratings, the shelf has room.
For demand, Apple's search popularity score through the Search Ads API is the only official figure either store publishes.
Should I target high-volume keywords?
Not at the expense of the long tail. Specific three-word phrases have lower demand but far higher intent, much weaker competition, and they convert better, which then feeds your ranking.
Can ranking for the wrong keyword hurt me?
Yes. If people find you through a term you are not relevant to and do not install, or install and uninstall, the store learns you do not belong on that shelf. You end up harder to rank for it than before.
How many keywords should I track?
Twenty to thirty for a single app is usually enough to cover brand, core category, long tail and a few reach terms without producing a dashboard nobody reads.
Do this automatically with ASOWeb
ASOWeb tracks every keyword in this guide daily across the App Store and Google Play, scores your metadata against how each store indexes it, and tells you when a ranking moves. The free plan covers 25 keywords and never expires.