It's heartening to see how many media sites in @speedcurve's Page Speed Benchmarks have sub-2.5s LCP times!
For some of the sites with poorer LCP, perceived #webperf / #ux isn't the issue. They're fast to start render. The main culprit is that the LCP element is just wrong.
The takeaway: don't just look at the numbers for your metrics. Visually validate them to make sure they're measuring the right things!
🟡 Delivering a fast UX to your users
🟢 Knowing the minute your site speed starts to suffer (including metrics like Core Web Vitals)
🔵 Fixing performance issues FAST
> Interaction to Next Paint (INP) is a Core Web Vital that measures how responsive a page is to interactions. Due to INP's scope, it can be difficult to identify why some interactions are slow. Learn how to use new Chrome APIs that provide detailed information on the causes behind slow interactions, and how to collect insights from your website's…
> Interaction to Next Paint (INP) is a Core Web Vital that measures how responsive a page is to interactions. Due to INP's scope, it can be difficult to identify why some interactions are slow. Learn how to use new Chrome APIs that provide detailed information on the causes behind slow interactions, and how to collect insights from your website's…
🟦 RUM INP attribution & subparts, including dimension filters (e.g. browser, connection type)
🟦 RUM update: lux.js v314
🟦 New synthetic test scripts
🟦 Upgraded test browsers for Industry Benchmarks
I had such a great time chatting with @grigs on the @cloudfour podcast! Among other things, we demystified Interaction to Next Paint – including what it does and does not measure. (It's a great metric, but it's definitely not one-size-fits-all!)
Another great analysis from @cliff. If your site uses a consent management platform (CMP), it's probably messing with your performance metrics.
Cliff breaks down the five most common issues – which affect all three Core Web Vitals, among other things – and he also provides some helpful scripting workarounds.
Every year I revisit the topic of web performance budgets. Here's my updated guide, including:
✅ What are performance budgets?
✅ Why are they a crucial tool in fighting page speed regression?
✅ Best metrics to track
✅ Determining thresholds
✅ Pro tips
One thing fast sites have in common: they use performance budgets to fight regressions and deliver a consistently fast experience to their users. Here's a VERY detailed guide that covers:
⭐ Budgets vs goals
⭐ Which metrics to track (including and beyond Core Web Vitals)
⭐ How to set thresholds
⭐ Getting stakeholder buy-in
⭐ Integrating budgets with your CI/CD process
These days there's a lot of talk about what INP is, and not enough talk about how to fix it. There's also a tendency to oversimplify INP, when it's not a simple metric. This must-read post by @andydavies tackles the hard stuff.
The next edition of Speed Matters is dedicated to INP: what it is, how to track it, how to validate it against your business/UX metrics, and – most important – how to improve it.
Slow backend times can hurt important front-end metrics like Start Render and Largest Contentful Paint. If you're using Akamai, Amazon Cloudfront, Cloudflare, Fastly, or Shopify, this post is a must-read. Among other things, @cliff provides clear examples of how you can use server-timing headers to get more visibility into your CDN.
I thought this post on Twitter about the #CoreWebVitals of the homepages of #javascript tools and frameworks was interesting, and I thought I’d cross post it here
In his analysis of how Interaction to Next Paint correlates to conversion rate, @cliff found no consistent correlation with Google's thresholds for 'Good', 'Needs Improvement' and 'Poor'.
For example, for one site, conversions suffer when INP is 100ms, which is well within Google's 'good' threshold of 200ms.
This is why you need to look at your own user data to understand what your INP thresholds should be.