How to Write Keywords in the App Store for ASO (2026)

The App Store gives you exactly 100 characters to tell Apple what your app is about — outside of your title and subtitle. That’s it. No tag cloud, no list of topics, no paragraph description. Just a single text field, 100 characters, commas as separators.

Most developers waste at least a third of it. They repeat words that already appear in their title, add spaces that eat up characters, include trademarked competitor names that get ignored, and then wonder why their app ranks on page 11.

This guide covers exactly how to write App Store keywords in 2026: what the field does, how Apple actually uses it, how to research the right terms, and how to format them so nothing gets wasted.

What Are App Store Keywords and Why They Matter

App Store keywords are a hidden metadata field in App Store Connect that directly controls which search queries your app appears for. Users never see this field. App reviewers don’t check it during review. It’s purely for the search algorithm.

When someone types a word into the App Store search bar, Apple’s algorithm checks several sources to decide which apps to show: the app name, the subtitle, and the keyword field. The keyword field is one of the three main ranking inputs Apple reads — which means a poorly-written keyword list is functionally the same as leaving a third of your ASO toolkit unused.

The stakes are real. According to industry ASO research (check the current figures at Sensor Tower or AppFollow), over 65% of App Store downloads come from search. Most of those searches happen on general terms — not branded searches for your app name. Keywords are how your app shows up on those general searches.

How the App Store Keyword Field Works — The Rules

Understanding the mechanics before writing a single keyword saves a lot of wasted effort. Here’s what Apple actually does with this field.

The 100-Character Limit

Apple gives you exactly 100 characters for the keyword field, including commas. The field is in App Store Connect under your app’s version metadata. It accepts a comma-separated list of words or phrases. No spaces after commas — that’s a common waste of 1 character per keyword.

The 100 characters include the commas themselves. So running,fitness,tracker uses 22 characters, but running, fitness, tracker uses 24. At scale, that waste adds up.

There is no per-keyword character limit. You can use single words or multi-word phrases. Phrases consume more of your 100 characters — which is why single words that Apple can combine on its own often perform better.

What Counts as a Keyword Source

Apple builds your searchable keyword index from three places:

1. App name — the title of your app (30 characters)
2. Subtitle — the line of text under your app name (30 characters)
3. Keyword field — the hidden metadata field (100 characters)

Words that already appear in your app name or subtitle are already indexed. Putting them in the keyword field wastes characters. Apple doesn’t double-index them and doesn’t reward repetition.

Your description text and user reviews are not part of the main keyword field. However, in-app purchase (IAP) names are indexed separately and can create additional indexed terms — a useful trick for apps with free and paid tiers.

How Apple Ranks Apps

Keyword presence gets your app into the candidate pool for a query. Ranking within that pool depends on several other factors: conversion rate (how many people who see your store listing actually download the app), ratings volume and recency, engagement signals, and the relevance of the keyword to the app’s core function.

This matters for keyword strategy. A keyword you rank on but don’t convert for actually hurts your ranking signal over time. Choose keywords where your app genuinely serves what users are looking for.

What Changed in 2025–2026

Apple Intelligence and Semantic Search

In 2025, Apple began integrating semantic search signals into App Store results on devices running iOS 18. This means Apple’s algorithm increasingly understands intent and synonyms — not just exact keyword matches. A user searching “budget app” can surface apps whose keywords include “expense tracker” or “money management” even without the exact phrase “budget app.”

The practical implication: you no longer need to stuff every possible synonym into your 100 characters. Cover your core terms precisely, and Apple’s semantic layer handles some of the variation. Focus on the specific high-intent terms that semantic matching is less likely to catch on its own.

Stricter Keyword Policy Enforcement

Apple tightened keyword guideline enforcement in 2026. Apps using competitor brand names in the keyword field — even subtle ones — are being flagged more frequently during metadata reviews. Keyword-stuffed titles (repeating the same word across title, subtitle, and keyword field) now trigger review flags rather than just being silently ignored.

If your app was rejected for metadata reasons, check the keyword field first. Apple’s updated guidelines explicitly prohibit: competitor names, trademarked terms you don’t own, irrelevant terms, and pricing language.

Custom Product Pages and Keyword Strategy

Apple’s Custom Product Pages (available since iOS 15, increasingly used for paid campaigns) don’t add to your keyword index — the indexed metadata is always the default product page. But they affect which keyword strategy is worth pursuing: if you’re running Apple Search Ads, you can target any keyword whether or not you rank organically. Pair your organic keyword list with your Search Ads keyword list to find gaps.

How to Research the Right Keywords

Tools You Can Use

No tool reads Apple’s keyword index directly — Apple doesn’t expose it. But several tools estimate keyword volume and difficulty based on panel data and App Store behavior:

• AppFollow — keyword tracking, rank monitoring, ASO audit
• Sensor Tower — keyword intelligence, competitor tracking (check current pricing on their site)
• AppTweak — keyword suggestions, difficulty scores, localisation-aware research
• Mobile Action — keyword research plus Apple Search Ads integration

For early-stage apps or developers not ready to pay for tools, Apple Search Ads’ keyword suggestion tool is free and shows keyword popularity scores from 5 to 100 based on Apple’s own data. Access it through your Search Ads account when you create a campaign.

Competitor Analysis

The fastest way to find working keywords is to look at what the top-ranking apps in your category already rank for.

• Search your main keyword in the App Store. Note the top 5–10 results.
• Use an ASO tool to see which keywords those apps appear for.
• Identify keywords they rank for that your app also fits — these are proven high-intent terms.
• Look for keywords where no single app dominates the top 3 — those are your best opportunities.

Don’t just copy a competitor’s keyword field. Their list was written for their app, their ratings, and their conversion rate. A term that works for a 4.8-star app with 100,000 reviews may not work for a 4.2-star app with 50 reviews.

Long-Tail vs. Short-Tail Keywords

Short-tail keywords (single words like “fitness” or “calendar”) have high search volume and very high competition. Long-tail keywords (phrases like “workout log app” or “shared family calendar”) have lower volume but much lower competition and higher purchase intent.

A practical split for most apps: use 20–30% of your 100 characters on 1–2 core short-tail terms where your app genuinely competes, and use the remaining 70–80% on specific long-tail phrases where you can realistically reach the top 10.

How to Write Your App Store Keywords — Step-by-Step Walkthrough

1 Audit What You Already Rank For

Before changing anything, know your baseline. Use an ASO tool to export your current keyword rankings. Note which terms you rank in the top 10 for — those are working. Note terms where you rank between 50–100 — those are candidates for optimisation. Anything below 100 is functionally not driving installs.

2 Build Your Keyword Pool

Generate a list of 50–100 candidate keywords using:

• Your category’s top searches (from Apple Search Ads suggestions)
• Competitor keyword research
• User language — read your reviews for the words users actually use to describe your app’s value
• Related searches — search your main keyword in the App Store and note the suggestions that auto-complete

Group keywords by theme. For a recipe app, you might have groups: “cooking tools,” “meal planning,” “diet-specific” (keto, vegan, etc.), and “food discovery.”

3 Prioritise by Relevance and Difficulty

For each keyword in your pool, assess:

• Relevance — does this keyword describe what your app actually does? If a user searches this and downloads your app, will they get what they expected?
• Difficulty — how competitive is this keyword? High-difficulty terms require an established ratings history to rank.
• Volume — is anyone actually searching this? Low-volume keywords waste your 100 characters even if you rank #1.

Prioritise: high-relevance, medium-difficulty, medium-to-high volume. Drop: any keyword that fails the relevance test, regardless of volume.

4 Format Keywords Correctly

This is where most developers lose characters unnecessarily. Follow these rules precisely:

• No spaces after commas. Write fitness,tracker,workout not fitness, tracker, workout.
• No articles or prepositions unless they’re part of a known search phrase. “a”, “the”, “for”, “in” waste characters.
• No punctuation other than commas. Hyphens, periods, and special characters are stripped or misread.
• Lowercase only. Apple’s indexing is case-insensitive. Capital letters add zero value.
• No repetition of words from your title or subtitle. If your app is called “Calm — Meditation & Sleep,” don’t put “meditation” or “sleep” in the keyword field.
• Singular or plural, not both. Apple’s algorithm handles both forms. run covers “running,” “runner,” and “runs.” Don’t waste characters on variants.
• No competitor names, trademarked terms, or irrelevant terms. These violate Apple’s guidelines and risk metadata rejection.

5 Enter Keywords in App Store Connect

Log into App Store Connect. Navigate to your app → App Store → the version you’re preparing → iOS App → scroll to the Keywords field under App Information.

Type your keyword string directly. The field shows a live character count — watch it drop toward 0 as you type. When you hit exactly 100, stop. Under 100 is fine; unused characters don’t help you, but going over 100 gets the field truncated.

Click Save, then submit the version for review (or submit just the metadata if you’re using App Store Connect’s phased metadata update). Keywords go live when the version or metadata update is approved. If you’re new to the submission flow, the full walkthrough in How to Publish Your App on the App Store and Google Play covers every step from metadata to release.

6 Monitor and Iterate

Keyword strategy is not a one-time task. Check rankings monthly. When a new iOS version ships, search behavior shifts. When a competitor launches a major update, rankings shuffle. Set a calendar reminder to audit keyword performance every 4–6 weeks.

If a keyword you added isn’t ranking in the top 50 after 4–6 weeks, it’s either too competitive for your app’s current authority, or it’s not a strong relevance signal for your app. Swap it for a lower-competition alternative and monitor the next cycle.

Common Keyword Mistakes That Hurt Your Ranking

FAQs

Key Takeaways

Getting keywords right is one of the few ASO levers you can pull without touching the binary — and it costs nothing but research time. Here’s the short version:

• The keyword field is 100 characters, commas count, no spaces after commas. Format precisely — wasted characters are lost ranking potential.
• Never repeat words from your title or subtitle. They’re already indexed; repetition wastes your budget.
• Apple now uses semantic search signals — you don’t need every synonym, but exact high-intent terms still matter for competitive queries.
• Competitor brand names violate Apple’s guidelines and increasingly trigger metadata rejection in 2026.
• Long-tail keywords beat short-tail for new apps — target specificity over volume until your ratings history builds authority.
• Each App Store locale has its own 100-character keyword field — localise for markets that matter to your app.
• Update keywords every 4–6 weeks, or with every major version update at minimum. The field you set at launch is stale within months.

Keywords are one piece of a bigger ASO puzzle. Once your keyword field is dialled in, your next lever is App Store screenshots — the highest-impact conversion asset on your listing. And if you’re still working toward your first real traction, the guide to getting your first 1,000 app downloads pairs keyword strategy with launch tactics and organic growth. If you’re building a mobile app and want the full App Store launch workflow handled for you — from metadata and keywords to screenshots and submission — AppOfWeb turns any website into a native iOS and Android app and walks you through every step of the publishing process.