Measure cache hit rate and the origin requests it avoids.
The cache hit rate is the share of total lookups that cache hits represents, expressed as a percentage. The same figure is also shown per 1,000 and as a "one in every N" odds statement, which is easier to reason about when the rate is very small. Absolute counts hide scale — a rate normalises the number so you can compare periods, channels or cohorts of different sizes, where higher is better.
Cache Hit Rate
Cache Hit Rate = Cache hits ÷ Total lookups × 100
Cache Hit Rate = Cache hits ÷ Total lookups × 100 The cache hit rate is the share of total lookups that cache hits represents, expressed as a percentage. The same figure is also shown per 1,000 and as a "one in every N" odds statement, which is easier to reason about when the rate is very small.
Absolute counts hide scale — a rate normalises the number so you can compare periods, channels or cohorts of different sizes, where higher is better.
This calculator takes 2 inputs: Cache hits, Total lookups. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.