What Is Search Popularity?
If you've ever looked at keyword data in Apple Search Ads, you've seen the Search Popularity (SP) score. It's a number from 5 to 100 that represents the relative search volume of a keyword on the App Store.
Apple doesn't publish raw search counts. Instead, they normalize everything into this 5-100 scale, where 100 represents the highest-volume keywords (think "facebook" or "instagram") and lower numbers represent progressively less searched terms.
The key word here is relative. An SP of 50 doesn't mean a keyword gets half the searches of an SP 100 keyword. The scale is exponential, which means the difference between SP 50 and SP 60 is much larger than the difference between SP 20 and SP 30.
How It's Calculated
Apple hasn't published the exact methodology, but through extensive testing and research from companies like SplitMetrics, we know the following:
Search Popularity is a 7-day moving average of search impressions, normalized against all other keywords on the App Store. This means:
- The score reflects the trailing 7 days of search activity, not real-time data
- It's smoothed to reduce noise from daily fluctuations (weekday vs weekend patterns, for example)
- It's relative to all other keywords, so if overall App Store search volume increases, individual SP scores can drop even without losing actual searches
Because of the 7-day averaging window, SP scores lag real-time search behavior by roughly 4 days. If a keyword suddenly goes viral on Monday, you might not see the full SP increase reflected until Thursday or Friday. This is important to understand when tracking trending keywords or seasonal terms.
The October 2025 Change
In October 2025, Apple made a significant change to how SP data is returned through the Search Ads API. Previously, you could get SP scores for virtually any keyword, even very low-volume ones that scored in the single digits.
After the change, Apple only returns SP scores for keywords with SP >= 35. Keywords below this threshold now return no popularity data at all. This effectively makes lower-volume keywords invisible to tools that rely solely on the Search Ads API.
For indie developers, this is actually a meaningful problem. Many of the best keyword opportunities for small apps exist in the SP 20-35 range — keywords with enough search volume to drive downloads but not enough competition to be unreachable. With this data now hidden, you need alternative signals like autocomplete priority scores to estimate volume for these keywords.
Converting SP to Real Search Numbers
The most widely cited research on mapping SP scores to actual impressions comes from SplitMetrics, who published an exponential formula based on their analysis of Search Ads campaign data:
Max Daily Impressions = 254.4443 exp(0.0615 SP)
This gives us a concrete reference for what different SP scores actually mean in terms of daily search volume:
| SP Score | Est. Daily Impressions | Est. Monthly Searches | Volume Label |
|---|---|---|---|
| 20 | ~870 | ~26,000 | Very Low |
| 30 | ~1,600 | ~48,000 | Low |
| 40 | ~2,800 | ~84,000 | Medium |
| 50 | ~5,600 | ~168,000 | Medium-High |
| 60 | ~10,000 | ~300,000 | High |
| 70 | ~18,000 | ~540,000 | High |
| 80 | ~33,000 | ~990,000 | Very High |
A few important caveats:
- These are maximum daily impressions, meaning the upper bound of what you could see if your app appeared for every search
- Actual impressions depend on your app's rank for that keyword — position 1 gets dramatically more impressions than position 10
- The formula is based on data from a specific time period and may drift as overall App Store search volume changes
- These numbers represent searches on the US App Store; other countries will have proportionally lower volumes
Why This Matters for Indie Developers
Understanding the exponential nature of SP is crucial for keyword strategy. Here's the practical takeaway:
SP 30-50 is the sweet spot for indie apps. These keywords get roughly 1,600 to 5,600 daily impressions — enough to meaningfully move the needle on downloads, but not so competitive that you need millions of reviews and a massive brand to rank.
Keywords with SP 70+ are dominated by well-established apps with huge install bases. Unless your app directly competes with them (and you have the reviews/ratings to back it up), these keywords are largely unreachable.
Keywords with SP below 25 are generally too low-volume to be worth optimizing for as primary targets, but they can be useful as long-tail additions to your metadata if they're highly relevant.
The Autocomplete Priority Proxy
For keywords below the SP 35 threshold (where Apple no longer provides data), there's an alternative signal: the App Store autocomplete API.
When you type in the App Store search bar, Apple returns autocomplete suggestions. Each suggestion includes a priority score from 0 to 10,000. While this isn't directly comparable to SP, higher autocomplete priority generally correlates with higher search volume. It's not as precise as SP, but it's free, requires no API access, and covers the long-tail keywords that SP now misses.
A rough mapping: autocomplete priority above 5,000 typically corresponds to SP 30+, while priority above 7,000 usually indicates SP 45+. Below 3,000, you're looking at very low-volume terms.
Getting Access to SP Data
To access Search Popularity scores, you need an Apple Search Ads account. The good news: it's completely free to create one. You don't need to run any ad campaigns or spend any money. You just need an Apple ID and a few minutes to set up the account.
Once you have an account, you can use the Search Ads API (specifically the keyword recommendations and targeting endpoints) to query SP scores for any keyword in any country where Apple Search Ads operates. Many ASO tools, including ours, let you connect your Apple Search Ads account to automatically pull this data.
The API uses OAuth 2.0 authentication and has generous rate limits for keyword lookups. It's the single most valuable free data source available for iOS ASO.
Key Takeaways
- SP is a relative, logarithmic score — small differences in SP mean large differences in actual volume
- The 7-day moving average introduces a ~4 day lag behind real-time trends
- Since October 2025, SP data is only available for keywords scoring 35+
- The SplitMetrics formula converts SP to estimated daily impressions
- For indie apps, target SP 30-50 keywords for the best effort-to-reward ratio
- Use autocomplete priority as a free proxy for keywords below the SP threshold
- Creating an Apple Search Ads account is free and unlocks SP data