# App Store keyword field builder

By Mika Heinonen (Indie iOS developer and maker of Fledly). Published 2026-10-28, updated 2026-10-28.
Canonical: https://fledly.app/tools/keyword-field-builder/

> List the searches you want your iOS app to rank for. The builder splits them into single words, skips words already in your app name and subtitle, and packs the most valuable ones into a valid 100-byte keyword field you can paste into App Store Connect.

*Interactive tool: open https://fledly.app/tools/keyword-field-builder/ in a browser to use it.*

## How the builder works

The App Store doesn't need whole phrases in your keyword field. It combines single words from your **app name**, **subtitle** and **keyword field** into searches. If your subtitle says *workout log* and your keyword field contains *weight* and *lifting*, the app can rank for "weight lifting log" without that phrase appearing anywhere.

So the builder:

1. Splits every search you list into single words.
2. Drops words that are already in your app name or subtitle, including singular and plural twins, because Apple indexes them once already.
3. Drops words that never help: your app's brand name, App Store category names, filler like "app", "the" and "free".
4. Gives each remaining word a value: the sum of the scores of the searches it helps complete. A word shared by several searches is worth more.
5. Packs the words with the most value per byte into 100 bytes, separated by commas without spaces.

It then shows which of your searches are **fully covered**: every meaningful word is somewhere in the name, subtitle or keyword field. Searches with a dashed outline show the words they still lack.

## Where to get the searches and scores

The builder is only as good as the list you give it. Good sources:

- **Apple's own search suggestions.** Type the start of a search into the App Store and note what it suggests. These are real searches.
- **Apple Ads search popularity.** Apple Ads shows a popularity score from 1 to 100 for App Store searches in each country. Paste it after each search, for example `gym log, 52`. Our [guide to Apple Ads search popularity](/blog/apple-ads-search-popularity/) shows how to read it.
- **Competitors' names and subtitles.** The words the top apps in your niche put in their names show what people search for.

Without scores, the builder treats your list as a priority order: the first search counts most.

The searches you can actually win depend on how strong the apps already ranking for them are, not only on popularity. [Fledly](/) tracks your ranks daily, shows Apple Ads popularity and difficulty for each search, and suggests new searches from App Store autocomplete. The free plan tracks 15 keywords.

## Tips for a better keyword field

- **Use singular or plural, not both.** Apple matches both forms from one.
- **Don't use your 100 bytes for your brand.** Your app name is indexed already.
- **Use every localization your country indexes.** In the US, Apple also indexes the Spanish (Mexico) keyword field, and many countries index two or more languages. That's extra keyword fields for the same store, explained in our [cross-localization guide](/blog/app-store-cross-localization/).
- **Change one thing at a time.** Keyword changes only go live with a new app version, so give each change one to two weeks before you judge it.

After building the field, run your whole listing through the [App Store metadata checker](/tools/app-store-metadata-checker/). The builder uses the same rules as Fledly's `build_keyword_field` tool for [AI assistants](/docs/mcp/), so Claude or ChatGPT can build fields for every localization in one go.

## Frequently asked questions

### Should I put phrases or single words in the App Store keyword field?

Single words separated by commas. The App Store combines words from your name, subtitle and keyword field, so "weight,lifting" covers the same searches as "weight lifting" and frees the space for another word.

### What is a good score to use for each search?

Apple Ads search popularity (1 to 100) is the best free number, because it comes from Apple's own search data. Without popularity, list the searches in order of importance and leave the scores out.

### Why did the builder leave out a word from my searches?

Either the word is already in your app name or subtitle, it's a singular or plural of a word you have, it's a filler word, an App Store category name or part of your brand name, or there was no room left. Words dropped for space are listed under the table.

### Can I build keyword fields for other languages?

Yes. Byte counts work for every language and script. Choose Finnish for Finnish plural rules; other languages use English plural rules, so check singular and plural duplicates yourself.