v149 · V8 · Bytecode Cache
Cache Impact Analyzer
Chrome 149 caches V8 bytecode for inline <script> blocks — keyed by SHA-256 hash of the script body. This tool estimates the compile-time savings your inline scripts gain on repeat visits, and shows what makes a script cache-eligible.
paste an inline script to analyze
Script size: 0 bytes
first visit (cold — no cache)
parse + compile—
execution—
cache written—
script size—
repeat visit (warm — cached bytecode)
parse + compile—
execution—
cache hit—
script size—
Click "Analyze script" to see estimated cache savings.
eligibility rules
run log
No runs yet.
how the cache key works
// Chrome 149 inline script cache key:
// SHA-256(scriptBody) + NetworkIsolationKey(origin)
//
// This means:
// - Same script text on every page → single cache entry
// - Different origin → different cache entry (security)
// - Changing even one character → cache miss (new hash)
//
// When the cache hits, V8 skips the parse + compile phase
// and deserialises pre-compiled bytecode directly.see also
- Cache Key Probe — verify cache key behaviour
- Cold vs. Warm — side-by-side timing comparison
- Feature index
implementation reference
Need the exact API surface, compatibility boundaries, errors, lifecycle, and source links? Read the matching gendn reference ↗