Web Performance and Site-Speed Insights
There are 251 articles on this blog. Find them all on the blog page.
Your website is slow. I can tell you why. Web performance affects every business: lost sales, conversions, running costs, user retention, SEO, and environmental impact. I’ll find your blind spots, explain what matters, and help you fix them.
Turn site-speed into a clear strategy. Learn what a one-second slowdown costs, how to measure its impact, whether your monitoring works, and what speed is worth to your bottom line. We’ll answer them and set priorities.
What’s better than one of me? A team of me. I’ll show your engineers how to find and fix the problems I can. They’ll learn the tools and methods, become self-sufficient, and keep your website fast for good. Never run slow again.
Learn More about my web performance services or Contact Me about a web performance project
Harry gave the team a strong footing for identifying performance issues on iPlayer. With his knowledge, we were able to roll out quick fixes to our audiences without the need for big rewrites, all within just two days.
Matthew Burrows, BBC iPlayer
Harry helped our team level up their scalable CSS architecture skills, and to say that he had a large impact on our work is an understatement. We can’t recommend him enough.
Addy Osmani, Google
Harry’s workshop was excellent; we left with tons of new ideas and techniques to improve both the CSS architecture and overall performance of Behance and Adobe Portfolio.
Jackie Balzer, Adobe
There’s a short list of people I whole-heartedly recommend for detailed performance work; Harry is right up there at the top.
Tim Kadlec
The CSS architecture I learned from Harry on the NHS project has changed the way I work. Bravo!
Josh Nesbitt
There are 251 articles on this blog. Find them all on the blog page.
Hi there, I’m Harry Roberts. I am an award-winning Consultant Web Performance Engineer, designer, developer, writer, and speaker from the UK. I write, Tweet, speak, and share code about measuring and improving site-speed. You should hire me.



I help teams achieve class-leading web performance, providing consultancy, guidance, and hands-on expertise.
I specialise in tackling complex, large-scale projects where speed, scalability, and reliability are critical to success.