The App Store keywords field in 2026: a 100-character playbook

Apple's App Store search guide lists the keywords field as one of four text signals search results are based on — "matches for your app's title, subtitle, keywords, and primary category" — alongside user behaviour like downloads and ratings. Its rules:

The last row is enforced in review. Guideline 2.3.7 tells you not to pack metadata with "trademarked terms, popular app names, pricing information, or other irrelevant phrases just to game the system", and says Apple "may modify inappropriate keywords at any time". Our Guideline 2.3 page covers what that rejection looks like.

One thing Apple doesn't settle: its search guide says 100 characters, while App Store Connect help says 100 bytes. For English the two are the same. For Japanese, Chinese or Korean, where a character can take several bytes, type the field into App Store Connect and trust its counter rather than any guide.

Apple doesn't publish how it combines words across your name, subtitle and keywords. But the rankings we measured for our case studies suggest it matches phrases built from words in different fields. In our Cal AI teardown (US App Store, October 6, 2026, measured with Astro), the app is named "Cal AI - Calorie Tracker" with the subtitle "Food & Macro Counter":

Three of those four phrases don't appear anywhere as written; each is assembled from two fields. We can't see Cal AI's keywords field, so it may help too — but the pattern is why practitioners write single words separated by commas rather than full phrases: one word can complete several searches when combined with words elsewhere in your metadata.

The other lesson came from our QUITTR teardown: App Store search returned no apps at all for "quit porn", "porn blocker", "porn addiction" and "stop porn". No keywords field can rank you for a search the store won't answer. If your category's literal words are restricted, put adjacent terms people actually use in your metadata instead.

According to ASOitis's App Store probes, the keywords field works best as a list of single words that complete phrases with your name and subtitle — Cal AI ranks in the top five for "food tracker", "calorie counter" and "macro tracker" with each phrase split across its name and subtitle — so a word you repeat in the keywords field is 100 characters you've spent twice.

1. Put your two most important phrases in the name and subtitle first. Those are visible and confirmed to count; the keywords field extends them.
2. List the other words people use for your app — features, problems, synonyms — one word per term where you can: photo,nutrition,diet rather than photo calorie counter.
3. Delete every word that's already in the name, subtitle or category. Apple says not to repeat them.
4. Keep one form of each word. Apple treats plurals of words you've already included as duplicates.
5. Cut filler and generic words — "the", "and", "app", "best", "free" — and anything not relevant to the app.
6. No spaces after commas, and no competitor names, even split into separate words.

Practitioners disagree on a few details, so treat these as tests rather than rules. Appfigures says words near the start of the list count more; Apple doesn't say so. AppTweak's plural study found that only 4.4 of 10 apps rank in the top 10 for both the singular and plural of a keyword on iOS — so if the plural is a big search in its own right, check where you rank for it before relying on Apple's duplicate rule.

This short Python script checks a keywords field against your name and subtitle: length in characters and bytes, spaces after commas, keywords of two characters or fewer, words already in the name or subtitle, and simple repeats and plurals. Paste your own three fields at the bottom.

import re

def words(text):
    return re.findall(r"[a-z0-9]+", text.lower())

def check(name, subtitle, keywords):
    problems = []
    if len(keywords) > 100:
        problems.append(f"{len(keywords)} characters; the limit is 100")
    if len(keywords.encode("utf-8")) > 100:
        problems.append(f"{len(keywords.encode('utf-8'))} bytes; App Store Connect counts up to 100 bytes")
    if re.search(r",\s", keywords):
        problems.append("a space after a comma wastes a character")

    taken = set(words(name)) | set(words(subtitle))
    seen = set()
    for term in filter(None, (t.strip() for t in keywords.split(","))):
        if len(term) <= 2:
            problems.append(f"'{term}': Apple wants each keyword longer than two characters")
        for w in words(term):
            if w in taken:
                problems.append(f"'{w}' is already in the name or subtitle")
            elif w in seen or w.rstrip("s") in seen or w + "s" in seen:
                problems.append(f"'{w}' repeats or pluralises another keyword")
            seen.add(w)
    return problems or [f"OK: {len(keywords)} of 100 characters used"]

name = "Cal AI - Calorie Tracker"
subtitle = "Food & Macro Counter"
keywords = "photo,nutrition,diet,weight,loss,protein,carb,keto,meal,scanner,fasting,intake,diary,journal,healthy"
for line in check(name, subtitle, keywords):
    print(line)

The example field is ours, not Cal AI's — its real field isn't public. Run against a typical first draft for the same app, calorie counter, food diary,diet,weight loss,calories,ai,photo,meal,meals,nutrition,protein, the script flags eight problems: a space after a comma, "calorie", "counter" and "food" already in the name or subtitle, "calories" and "meals" as repeats, and "ai" as both too short and already in the name. The rewritten field above uses exactly 100 characters with none of them.

Every localization has its own 100-character keywords field, and when you add a language Apple doesn't copy your keywords into it. Apple's localization help says users "can search for your app using localized keywords in all countries or regions where the App Store supports" that language. Its storefront table lists which languages each store supports:

Read together, those two pages are why a Spanish (Mexico) localization can add keyword reach in the US store, and an English (U.K.) one in Australia, Germany or Mexico. Apple doesn't document how much weight those extra fields carry, and the localized page is what speakers of that language see — so write it properly in that language. Our iOS app localization guide covers which languages to ship first.

• The main field needs a new version. Apple's list of properties you can edit at any time doesn't include keywords, and its product page guide says the subtitle and description change "when you submit a new version". Promotional text is the exception that changes any time — and Apple says it "doesn't affect your app's search ranking".
• Custom product pages can have keywords. Since October 2025 you can assign keywords to each custom product page so it "can appear in search results for those selected keywords instead of your default product page". The keywords must come from your latest approved version, and Apple recommends a unique set for each page.
• Measure before you change. Apple confirmed at WWDC26 that it doesn't provide keyword-level data in App Store Connect, so track ranks with a tool before and after each version — otherwise you can't tell which change worked.