So excited to be paired with @paulcalvano.bsky.social for this double-header on PerformanceObserver next week! Paul will take a deep dive into the HTTP Archive. Then I'll break down the "performance plateau" – why you need to know it and how to find it. performanceobserver.dev/events/episo...

Querying the HTTP Archive and finding your Performance Plateau | PerformanceObserver

In this episode, Paul Calvano dives deep into querying the HTTP Archive dataset to uncover web trends, while Tammy Everts breaks down the "Performance Plateau", explaining why identifying your specifi...

performanceobserver.dev

In our rush to align page speed with SEO and business metrics, have we in the #webperf community lost our way? In this post, based on the keynote I gave at #PerfNow a few months ago, I explore how it's not too late to bridge the gap between pragmatism and user delight. www.speedcurve.com/blog/fast/

SpeedCurve | How fast is fast enough? Rethinking web performance in pragmagical terms

Always remember: We're in the business of creating experiences for other humans.

speedcurve.com

ICYMI, here's a wrap-up of exciting #webperf and #ux highlights from 2025! ⭐ Broad browser support for LCP and INP (W👀T!) ⭐ New metrics & visuals for measuring user happiness ⭐ Deeper metrics for JS diagnostics ⭐ Better budgets = easier regression-fighting www.speedcurve.com/blog/2025-we...

SpeedCurve | 2025 was a big year! Here are some highlights...

From broad browser support for key metrics to nuanced metrics for diagnosing issues, 2025 has been filled with wins.

speedcurve.com

I ❤️ writing these annual wrap-up posts. From broad browser support for key metrics to nuanced metrics for diagnosing issues, 2025 has been filled with huge wins — not just for @speedcurve.com but for our entire #webperf community. Go, us! www.speedcurve.com/blog/2025-we...

SpeedCurve | 2025 was a big year! Here are some highlights...

From broad browser support for key metrics to nuanced metrics for diagnosing issues, 2025 has been filled with wins.

speedcurve.com

If you only have time to do ONE THING to make your site holiday-ready (so you can relax and enjoy the next few days off) it's this: CREATE PERFORMANCE BUDGETS 😀 No code changes required 😀 Literally takes just 1-2 minutes 😀 You get alerts if your pages slow down 👉 www.speedcurve.com/web-performa...

🚨 New EMA Impact Brief: Embrace + @speedcurve.com is a big step forward for modern #observability. Together they deliver deeper user context, unified mobile + web + synthetic visibility, and an OTel-first foundation built for AI-ready reliability. Read more ➔ ow.ly/tsXY50XxcpZ

Impact Brief: Embrace Acquires SpeedCurve, Advancing User-Focused Observability with Deep Web Performance Insight

EMA explores how Embrace and SpeedCurve’s combined strengths create a comprehensive experience layer across mobile, web, and backend systems.

ow.ly

What happens when observability merges with front-end performance monitoring? You get the best of all worlds — performance, reliability, and UX across web and mobile! Join our founder @markzeman.com, CPO @cliffcrocker.bsky.social, and @embrace.io President Andrew Tunall on December 9 to learn more!

Embrace@embrace.io · 9mo ago

🔥 Fireside chat: The future of user-focused #observability With the Embrace + @speedcurve.com acquisition now live, hear what’s ahead from Andrew Tunall, Mark Zeman, and Cliff Crocker. 📅 Dec 9 at 11 AM PST 📍 Save your seat ➔ ow.ly/M6QQ50XvcB2

Unoptimized images are STILL a common problem, and they hurt things like: 🙁 #A11y 🙁 #webperf and #UX metrics like LCP and CLS 🙁 Conversions 🙁 #SEO 🙁 Sustainability I'll be talking about this (and solutions!) today (12:15pm PT / 3:15pm ET) at #PixelPalooza. Get your FREE ticket: lnkd.in/g_N8YFrs

Third parties represent a MASSIVE potential single point of failure for your site. 1. AUDIT & remove unused tags 2. DEFER or load asynchronously 3. TRACK scripts & create #webperf budgets 4. KNOW your SLAs with vendors 5. CREATE a playbook for failures 👉 www.speedcurve.com/web-performa... #ux

Third-Party Web Performance | SpeedCurve

Ads, analytics, and social widgets can seriously hurt page speed. Find out how to measure and optimize the third parties on your pages.

speedcurve.com

🎄 Holiday Readiness Tip 7: Track your CDN! CDN performance can be a black box. Did you know you can track CDN health using Server Timing headers? 👉 How to get backend transparency from your CDN: www.speedcurve.com/blog/server-... 👉 More holiday readiness tips: www.speedcurve.com/blog/holiday...

SpeedCurve | 2025 Holiday Readiness Checklist (Page Speed Edition!)

25 things you can do to keep your site fast and your users happy through the holidays and beyond!

speedcurve.com

#PixelPalooza is coming up this Thursday! This awesome FREE online event covers how to make sure all those helpful images and videos on your site don't hurt #webperf and #a11y. I'm joining @seancdavis.com to talk about the hidden cost of media on the web. Get your ticket 👉 cfe.dev/events/pixel...

PixelPalooza 2025

PixelPalooza will explore all the best practices we, as developers, can leverage media like images, video, audio and documents across our sites and applications.

cfe.dev

Video of my @perfnow.nl keynote is up! In this talk, I challenged the false choice between magic and pragmatism. Don't settle for "fast enough". Instead, aim to create a user experience that's #pragmagical — blending user delight with measurable business impact. conffab.com/presentation...

How Fast Is Fast Enough?

<p>It sounds like a simple question, but if you’ve been working in performance long enough, you know the answer is far from straightforward. In this Day 1 keynote, Tammy asks questions—from neuroscien...

conffab.com

SpeedCurve has been acquired by @embrace.io! We’re combining forces to connect performance, reliability and UX across web and mobile apps. And yes, our team and tools will remain the same. 😀 Our founder @markzeman.com shares how our 12-year journey led us here: www.speedcurve.com/blog/perform...

I love heatmaps so much! They're the best way to get instant insight into where #webperf issues are lurking across your site. Taking it even further, you also get breakdowns across dimensions like page label, browser, device, and location. *chef's kiss* 👉 www.speedcurve.com/blog/new-hea...

SpeedCurve | NEW! Heatmaps now available on Favorites Dashboards

We’ve finally added heat maps to your Favorites (custom) dashboards — one of our most requested features ever! It feels great to finally make this available to everyone.

speedcurve.com

Slides from my @perfnow.nl talk — How Fast Is Fast Enough? — are up! If you’re at #PerfNow (or even if you’re not) I’d love to talk about creating a delightful experience for your users. speakerdeck.com/tammyeverts/...

How Fast Is Fast Enough? [PerfNow 2025]

It sounds like a simple question, but if you've been working in web performance long enough, you know the answer is far from straightforward. In this ke&hellip;

speakerdeck.com

Sharing a few of the sources I cited during my #PerfNow talk, I’ll start with this one… Here’s a deeper dive into how to create correlation charts that help you see the relationship between performance metrics and business/engagement metrics. www.speedcurve.com/blog/site-sp...

SpeedCurve | Correlation charts: Connect the dots between site speed and business success

If you could measure the impact of site speed on your business, how valuable would that be for you?

speedcurve.com

Another source from my #PerfNow talk… Here’s why you need to know the performance plateau for your site. www.speedcurve.com/blog/web-per...

SpeedCurve | Why you need to know your site's performance plateau (and how to find it)

Have you ever wondered why your site got faster, but your business and user engagement metrics didn't change? Here's why.

speedcurve.com

For #PerfNow folks who want to go even deeper on Long Animation Frames, @andydavies.me wrote the definitive guide. www.speedcurve.com/blog/guide-l...

SpeedCurve | The Definitive Guide to Long Animation Frames (LoAF)

LoAF lets you identify problem scripts, quantify the impact of third-party scripts, and improve the user experience. Here's everything you need to know to get started.

speedcurve.com

Learn more about Total Blocking Duration (TBD), the experimental new metric that @andydavies.me is pioneering. #PerfNow www.speedcurve.com/blog/long-an...

SpeedCurve | NEW! Monitor Long Animation Frames and get to the bottom of your JavaScript issues

Now you can monitor Long Animation Frames (LoAFs) and fix the third parties and other scripts that are hurting your user experience!

speedcurve.com

Making Sense of Long Animation Frames… The slides from my #PerfNow talk are available on Notist noti.st/andydavies/9...

Making Sense of LoAF by Andy Davies

Over time the web has become more reliant on JavaScript… but we’ve very little information on how its growth is affecting our visitors’ experience.

noti.st

And last (but definitely not least) here’s @cliffcrocker.bsky.social’s super-interesting analysis of INP and its correlation with UX and business metrics. #PerfNow www.speedcurve.com/blog/INP-use...

SpeedCurve | Does Interaction to Next Paint actually correlate to user behavior?

If you make INP faster, will it actually improve the user experience... and help your business? Here's our analysis.

speedcurve.com

We ❤️ making users happy! One of our customers (a large healthcare system) had this to say about our tools and service — including kudos to our amazing @cliffcrocker.bsky.social! 👉 Learn how we collaborate with you to build your #webperf and #ux practice: www.speedcurve.com/why/collabor...

Excessive JS is a UX monster. It hurts important metrics like LCP and INP, which in turn hurts bounce rate and conversion rate. I dug into this topic in a recent post, where I compared the #webperf of landing pages for well-known sites, from Apple to Uber. www.speedcurve.com/blog/campaig...

SpeedCurve | Are your retail landing pages killing conversions?

How do the campaign landing pages of leading websites compare? Who's fast, who's slow, and what's causing their page speed bottlenecks?

speedcurve.com

I've been exploring @speedcurve.com's new Vitals Overview dashboard with some customers for a week or so now, and all I can say is WOW. Not only is it fun to play with, it also halves the time it takes to investigate #webperf and #ux issues. 👉 Take a quick tour: www.speedcurve.com/blog/a-smart...

SpeedCurve | NEW! A smarter way to spot performance issues

We’re excited to announce the launch of the Vitals Overview dashboard in SpeedCurve. It's your new starting point for exploring the performance of your site.

speedcurve.com

We just added @csswizardry.com to our Web Performance Heroes starter pack! (Yes, it's a bit late, but better late than never.) Every month, we honour a new hero and add them to this list. Follow along and meet the folks without whom the web would be a sadder and slower place. go.bsky.app/FTbRtFk

Every fall I hear so much FOMO from folks who missed @perfnow.nl. Don't let it happen to you! We have amazing speakers sharing the newest best practices for the #webperf topics you care about: AI, APIs, #a11y, CSS, JS, frameworks, tools, culture, workflows & more! Get your tickets soon! perfnow.nl

performance.now(); 30th and 31st of October, Amsterdam

On 30th and 31st of October, 2025, the sixth edition of performance.now() will take place in Amsterdam—a single track conference, covering today’s most important web performance insights.

perfnow.nl

How fast is fast enough? I'll be exploring this question in my #PerfNow keynote. I hope to see you there! And if you have your own thoughts on this question, I'd love to hear them! #webperf #sitespeed #pagespeed #ux

performance.now() conference@perfnow.nl · 11mo ago

performance.now() is coming! @tammyeverts.com asks a seemingly-simple question: How Fast Is Fast Enough? She'll touch on questions — ranging from neuroscience to business metrics — to get you thinking about how you create, measure, and report your performance goals. perfnow.nl/speakers.htm...

Retail ad campaigns are $$$ — yet campaign landing pages are often the slowest pages on a site. That slowness has a direct impact on conversions. 💸 I tracked landing pages for 19 leading sites to see who's fast, who's slow, and what's causing their bottlenecks. www.speedcurve.com/blog/campaig...

SpeedCurve | Are your retail landing pages killing conversions?

How do the campaign landing pages of leading websites compare? Who's fast, who's slow, and what's causing their page speed bottlenecks?

speedcurve.com

Schedule schedule on the wall, who has the best line-up of them all? perfnow.nl/schedule.html

I recently started instrumenting both @cloudflare.social and browser cache hits/misses and the numbers, while obvious, are compelling. The best request is the one that never happens. Check that 0ms TTFB 😍 ℅ @speedcurve.com