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We’re hiring: AI Content Production Specialist (Remote)
Nexlane
Web Development

Core Web Vitals & Speed Optimization

Measuring first, then fixing what actually makes the page slow.

Speed work is diagnosis before optimisation. We measure a site with field data from real visitors and with lab tools, find what is genuinely costing time, and fix the causes rather than chasing a score with tricks that do not hold.

Tools we work in

  • Chrome DevTools
  • Lighthouse
  • PageSpeed Insights
  • WebPageTest
  • Cloudflare
  • Sentry

Scope

What this covers

The specific work included when you engage us for this service.

  • Field data analysis from real users, separated by device and connection
  • Largest Contentful Paint, Interaction to Next Paint and layout shift diagnosis
  • Image delivery, sizing and modern format conversion
  • JavaScript and CSS reduction: splitting, deferring and removing unused code
  • Font loading, server response time and caching strategy fixes
  • Before-and-after measurement so each change is proven rather than assumed

What you receive

  • 01A measurement baseline from field and lab data before any change
  • 02Fixes applied alongside a record of what changed and its measured effect
  • 03A short list of remaining causes and the honest effort each would take

Questions

Core Web Vitals & Speed Optimization, answered

Can you guarantee a green Lighthouse score?

No. Lighthouse is a lab estimate that varies with the machine running it, and part of the score sits outside the code: third-party tags, the visitor's network, a CMS plugin you need. We target good Core Web Vitals in field data, which is what search and visitors actually experience, and we show you the measurements instead of a badge.

How much speed can the average site recover?

It varies too much to promise a number. In practice the largest gains usually come from images, unused JavaScript and third-party scripts. We measure your site first and tell you where the time is going before quoting any work on it.

Tell us where the manual work is

A 30-minute call. We map the process, tell you what we would automate or build first, and what it costs. No retainer before you agree the scope.

  • No retainer before scope is agreed
  • Written plan you can act on alone
  • Worldwide delivery, on your hours