Using the 100-Byte App Store Keyword Field: Deduplicate, Merge, Compress and Avoid Bad Splits

Apple's official reference says the App Store Connect keyword field allows up to 100 bytes (see Platform version information). Marketing pages sometimes say "100 characters". For plain English the two roughly coincide, but for Chinese, Japanese and Korean they differ a lot: a CJK character usually takes 3 bytes in UTF-8, so 100 bytes often fits only about thirty characters plus commas.

This site's ASO keyword combiner deduplicates, merges and compresses keywords within the byte budget and flags risky splits; pair it with the ASO character/byte counter to check whether your title, subtitle and keywords are over the limit. The steps below follow the order you'd actually work in, and no search volumes are made up.

How to fill the field without wasting bytes

Apple's product page guidance says keywords should be separated by commas, with no spaces after the commas; spaces are fine inside a phrase (the official example is similar to Property,House,Real Estate). See Creating Your Product Page.

Actionable rules:

1. Count bytes, not "how many words it looks like". For a Chinese (or other CJK) localization, open a byte counter first, then decide which words to cut.
2. No space after commas. notes,todo and notes, todo usually index the same, but every space in the latter burns budget.
3. Don't repeat words already in your app name or subtitle. Apple states that the app name and company name are already searchable; repeating them in keywords costs bytes with no gain. Your primary category name generally doesn't need to go in the keyword field either.
4. Make each keyword longer than two characters (Apple sets length expectations for individual entries). Piling up single characters or letters is hard to index and wastes commas.
5. Don't include other apps' or companies' names. The reference page explicitly disallows this.

Google Play has no equivalent "100-byte keyword field"; its short and full descriptions are counted in characters. Don't carry Apple's byte habits over to Play unchanged, and don't paste the same Chinese keyword string into the "keywords/tags" fields of Chinese Android store consoles without checking each channel's length rules.

What the keyword combiner solves

Candidate keywords usually come from brainstorming, competitor lists and users' own words. Before pasting them into the console, you need three steps:

1. Deduplicate: the same word appearing several times, or duplicating the title or subtitle.
2. Merge and compress: keep as many useful words as possible within 100 bytes, normalize commas and strip meaningless spaces.
3. Flag bad splits: Apple splits the keyword field and recombines terms to cover long-tail searches. In English, photo,editor may cover photo editor; in continuously written Chinese, a wrong split can produce adjacent combinations you don't want, or break apart a proper term that should stay whole.

The tool typically outputs two versions (exact labels as shown on the page):

• Safe version: more conservative splitting and retention, prioritizing fewer odd adjacent combinations.
• Maximum-coverage version: keeps more word roots within the byte budget for more long-tail combinations, but is also more likely to produce "two words stuck together that read awkwardly".

There's no search volume panel: the tool doesn't produce fake ranking data. The quality of your keyword list still depends on your own research; the tool only cleans up the string within the byte limit and marks split points worth a second human look.

Recommended steps

1. List candidate words in a spreadsheet or notes app (features, use cases, synonyms); don't worry about order yet.
2. Open /tools/aso-char-count, paste your app name and subtitle separately, note the words already used, and remove duplicates from your candidates.
3. Open /tools/aso-keyword-combiner and paste the remaining candidates (one per line or comma-separated).
4. Watch the byte usage bar: if you're over 100, cut words that are extremely competitive, unrelated to your features, or clearly never searched.
5. Compare the split warnings for the safe and maximum-coverage versions. If an adjacent combination reads as ambiguous or sensitive, start from the safe version and manually reorder words, or remove one of the roots.
6. Copy the final string into the keyword field for that language in App Store Connect, save, and confirm it isn't truncated using TestFlight or the unpublished metadata preview.
7. When you update, reuse the same keyword file and swap terms incrementally; rerun the combiner and counter after each change.

Extra notes for Chinese localizations

• Bytes are tight: keep the feature words users actually search for, and cut back on adjectives.
• Protect whole terms: if a brand's pinyin or a proper product name must appear, make sure commas don't break it into meaningless fragments, and don't split it into two single characters hoping the system will join them back.
• Simplified vs Traditional, and regions: Simplified Chinese and Traditional Chinese are separate localizations. Maintain separate keyword lists rather than sharing one byte string "to cover both".
• Divide the work with screenshot copy: the keyword field serves search matching; the headlines on product page screenshots serve conversion. For screenshot layout see /preview; for store rules see the compliance check. The two can echo each other, but screenshot headlines don't need to (and shouldn't) cram in every word from the keyword field.

Common mistakes

How to check after changing keywords

After saving metadata, don't just rely on the "Saved" message in App Store Connect. Do three small things:

1. Paste the final keyword string back into /tools/aso-char-count to confirm it's still ≤100 bytes with no stray spaces.
2. Search the App Store, signed out or with a fresh account, for a set of terms you really care about (feature and use-case words), and see whether competitors and your app show up in relevant results. This is qualitative observation, not ranking-tracking software.
3. If a version changes only keywords and not the binary, the review and go-live timing for that localization follows Apple's current policy; don't assume "saved means instantly live everywhere".

Keep the keyword file in the same product folder as your screenshot sources, labeled with the date and language code (e.g. zh-Hans), so a teammate doesn't overwrite the new string with an old one.

How it fits with the site's other tools

After keywords, your metadata still needs to match your visuals: does the first screenshot clearly state the core feature, and is the subtitle competing with the keywords for the same phrase? For design references, browse /nav; for sizes and submission files, use screenshot sizes and the compliance check. ASO isn't only about the keyword field, but the keyword field is the one field with a hard 100-byte cap. Get it right first, then work on descriptions and ratings strategy.

Field rules follow Apple's current documentation; if the App Store Connect interface conflicts with an older tutorial, go by App Store Connect and the Platform version information reference.