Core Web Vitals 2026: What actually matters
Two years since INP replaced FID. Data from 60 sites in our portfolio shows which metrics deserve a budget — and which don't.
By Mert Can Yılmaz · Tech SEO Lead
In March 2024, FID was officially retired and INP took its place. Most agencies treated the change as a tooling update. For us, it was a chance to revisit our measurement philosophy.
After analyzing the last 12 months of CrUX data across 60 sites, a clear pattern emerged: improving LCP drives revenue +3–7%, while improving CLS had no effect on conversion (as long as it stayed near zero). INP, on the other hand, is a measurable conversion blocker on mobile checkout pages.
In practice that means a time-boxed audit should follow this order: 1) get LCP under 2.0s, 2) get INP under 100ms, 3) keep CLS near zero. Optimization campaigns that ignore this order spend the budget in the wrong place.
Next quarter we're watching the rumors of a Google 'Speed Update v2.' If an official announcement lands, expect a detailed note on what it means for our clients.