What a Fine Conversion Value Is
A fine conversion value is the detailed half of Apple's conversion value system. It is a number from 0 to 63 that an iOS app sets after install to describe what the new user did, and Apple reports it back in the first SKAdNetwork postback or AdAttributionKit postback when privacy thresholds allow.
Before SKAN 4 there was only one kind of conversion value, so the term conversion value usually meant this number. SKAN 4 added the three-level coarse conversion value, and "fine" became the name for the original 64-value field.
When It Is Reported
The fine value only appears in the first postback, which covers days 0 to 2 after the first app open. It is released only when the install reaches one of the two highest crowd anonymity tiers. Below that, the first postback falls back to the coarse value or to no value at all.
In practice, large campaigns on large publisher apps see fine values on most installs, while small campaigns, niche countries or new creatives see them rarely. That uneven coverage is the main thing to keep in mind when reading fine values across campaigns.
How Teams Encode Fine Values
Advertisers choose what each of the 64 numbers means. Three patterns cover most mappings:
- Revenue buckets. Each value stands for a revenue range, for example value 10 for $1 to $2 and value 20 for $5 to $10. Good for apps that monetize early through purchases or ads.
- Event flags. Values encode which key events happened, such as registration, tutorial complete and first purchase. Good for apps where early intent predicts later revenue.
- Hybrid. Lower values encode funnel events and higher values encode revenue ranges, so both non-paying and paying users carry a signal.
Whatever the pattern, the values need an order. Networks optimizing toward value read higher numbers as better users, so a mapping where 40 means less than 12 confuses their models.
Writing the Value from the App
The app updates the fine value through Apple's update API as the user completes mapped events, usually through the MMP's SDK rather than custom code. The SDK keeps the current value, compares each new event against the mapping, and writes the new value along with the coarse value and a lock decision.
Locking matters. If the app locks the value as soon as a user hits the top of the mapping, the first window closes early and the postback arrives sooner. If it never locks, the postback waits for the full 48 hours plus Apple's random delay.
In Linkrunner, you configure events, priority and revenue ranges in your conversion value mapping, and Linkrunner generates the fine and coarse values for Google and Meta. The iOS SDK writes them through SKAdNetwork and, on iOS 17.4 and later, through AdAttributionKit.
Reading Fine Values in Reports
Decode fine values back to the events and revenue they stand for before you compare campaigns. A distribution chart, how many installs reported each value, shows whether a campaign drives registrations, purchases or nothing at all. The SKAN dashboard in Linkrunner shows that distribution alongside privacy tiers and trends.
Two cautions. First, campaigns with lower volume report fewer fine values, so comparing their averages against large campaigns overstates the difference. Compare within similar tiers, or use coarse values for the comparison. Second, a mapping change breaks trend lines. Note the date of every mapping change and avoid comparing values across it.