TL;DR
A store headline gets one job: communicate the primary benefit before the line truncates on mobile. The reliable workflow is to have an AI generate 15-20 candidates that respect the exact platform character limit, then rank them by hand. Models miscount characters often, so you verify the top picks yourself before any of them ship. The copy-ready prompt and the per-platform limits below get you there in one pass.
The actual character limits (as of June 2026)
The single most common failure is a headline that reads great in your doc and gets cut off in the store. Each platform has its own ceiling, and the visible portion on mobile is usually shorter than the hard limit. Feed the AI the hard limit, but write toward the visible cut.
| Platform | Field | Hard limit | What shoppers actually see |
|---|---|---|---|
| Apple App Store | Title | 30 chars | Full 30 in most layouts |
| Apple App Store | Subtitle | 30 chars | Shown under the title |
| Apple App Store | Keyword field | 100 chars | Hidden, indexed (comma-separated, no spaces) |
| Google Play | Title | 30 chars | Full 30 |
| Google Play | Short description | 80 chars | Above the fold on the listing |
| Amazon | Product title | 200 chars (category caps lower) | First ~70-80 on mobile |
| Etsy | Listing title | 140 chars | First ~40-50 in search results |
Two platform-specific traps worth knowing:
- Amazon caps vary by category. The 200-character ceiling only applies to some categories. Electronics is capped at 150, Apparel at 125, and Pet Supplies at 80. As of the 2026 title guidelines, special characters (
!,$,?) are no longer allowed unless they are part of a registered brand name, and repeated words are restricted. Confirm your category’s limit in Seller Central before generating. - Etsy front-loads keywords. Only the first roughly 40-50 characters appear in search results, so your primary keyword has to come first. Etsy’s own guidance favors pipe-separated clusters —
[primary keyword] | [modifier keyword] | [occasion or recipient]— and titles that land in the 100-140 range without reading like keyword soup.
When AI is the right tool for this
- You need 10-20 candidates fast for an A/B or ad-headline test.
- You are launching the same listing across multiple languages.
- You want a spread of angles (benefit, curiosity, contrarian) to find what converts.
- You are iterating weekly on conversion data and need fresh variants each round.
When not to lean on AI alone
- Brand-defining headlines for a hero product, where a single word carries weight.
- Regulated categories (medical, finance) where every claim must be human-vetted.
- Trademark territory — the model has no idea what your legal team has cleared.
What to feed the AI
A weak input package is the real reason most AI headlines come back generic. Give it all of this up front:
- Product name and category.
- Primary benefit in one plain sentence.
- A secondary benefit or hook.
- The exact platform field and its hard character limit.
- The top 3 keywords you must include for ASO/SEO.
- Two existing listing titles whose tone you like, and one you dislike.
Copy-ready prompt
Replace the bracketed placeholders with your own values. Keep the per-angle split — it forces variety instead of fifteen rewrites of the same line.
You are an ASO and marketplace copywriter.
Generate 15 store-listing headline candidates for [product_name].
Platform / field: [platform_and_field, e.g. "Apple App Store title"]
Hard character limit: [char_limit] including spaces
Primary benefit: [primary_benefit]
Must include at least one keyword from: [keyword_list]
Audience: [audience]
Tone to match: [good_example_1], [good_example_2]
Tone to avoid: [bad_example]
Mix angles across the 15:
- 5 benefit-led (e.g. "Plan trips 3x faster")
- 4 curiosity-led (e.g. "The notes app your team forgets it's using")
- 3 contrarian (e.g. "Not another habit tracker")
- 3 keyword-stacked for pure ASO
Output a numbered list. After each headline, print [character count]
and a one-word angle tag (benefit / curiosity / contrarian / aso).
Never exceed the hard character limit, including spaces.Any current model handles this well — GPT-5.5, Claude Sonnet 4.6, or Gemini 3.1 Pro (all June 2026). For multilingual runs, Gemini 3.1 Pro and GPT-5.5 tend to keep character counts tighter across non-Latin scripts, but you still verify by hand.
How to check the output before it ships
The numbered list with character counts and angle tags makes ranking fast. Then run this gate on your top picks:
- Recount characters yourself. Models miscount, especially near the limit. Paste your top 5 into the platform’s own field or a character counter and confirm each fits.
- Read in the real truncation preview. App Store Connect, Play Console, and Etsy all show a live preview. A headline that fits the hard limit can still get cut at the visible boundary.
- Strip the generics. Delete any line that could describe three other apps in the same category. If swapping the product name leaves it just as true, it is filler.
- Test the finalists. Run the top 2-3 through SplitMetrics or Storemaven, or a cheap ad-headline split test, before committing to a store update.
Common mistakes
- Trusting the model’s character count without recounting.
- Stuffing keywords until the line stops being a sentence — Etsy and Amazon both penalize this now.
- Writing for the product team instead of a first-time visitor who has never heard of you.
- Reusing one English headline across US, UK, and AU markets, which respond to different framings.
- On Amazon, leaving in special characters or repeated words that the 2026 guidelines now reject.
Keep improving the system
Save your two best-converting headlines per quarter into a “winners” file and feed them as tone examples next round — the model gets sharper the more it sees what actually wins for you. Track install or click conversion by headline variant, and retire the angles that never place. Refresh quarterly for established listings, monthly for new launches.
FAQ
- How many candidates should I generate? 15-20. Fewer and you settle for the first line that fits; more and ranking gets slow.
- Should the headline and subtitle echo each other? No. They complement: headline carries the benefit, subtitle carries proof or context. Repeating the benefit wastes 30 characters.
- Do emojis help in store titles? Occasionally on Play and Etsy, almost never on the App Store, and Amazon rejects them outright in 2026 unless part of a brand. Test sparingly.
- Does the App Store keyword field affect my headline? Not directly, but it earns you indexing for terms you do not need to cram into the visible title — so you can write the title for humans and let the 100-character keyword field do the ASO work.
- How often should I refresh? Quarterly for established apps, monthly for new launches or anytime conversion dips.
Related
See marketplace listing title prompts, app store listing prompts, and product description prompts for the paired listing copy. Apple’s own product page guidance and Etsy’s title guidance are the authoritative sources for current rules.
Tags: #AI writing #Workflow