Cache Hit Ratio Explained: The Formula and Why It's the Key Metric for Cutting Latency
blaizedsouza · x · 2026-09-19
A shared explainer on Cache Hit Ratio: the share of requests served from cache rather than the primary store (database, API, etc.).
- Formula: Cache Hit Ratio (%) = (Cache Hits / Total Lookups) × 100.
- Example: of 10 requests, the first misses and hits the database, the next 9 hit cache — a 90% ratio.
- Author's point: improving hit ratio is the way to cut latency, and anyone using cache should measure it.
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