Website performance & speed, explained
Everything you need to know about making your website fast — why it matters, what slows sites down, and how to fix it.
A slow website costs you visitors, customers, and search rankings. This section explains what page speed really means, why it matters for your business, and what you and your team can do about it — in plain English.
Start here
If your site feels slow right now, jump to What slows websites down or How to measure your site's speed. If you just want to understand the big picture, start from the top.
If you only read three things
- Why website speed matters — the business case.
- What slows websites down — diagnose before you fix.
- Images & page speed — usually the highest-impact win.
Why speed matters
Why website speed matters
How a slow site affects your visitors, your revenue, and your Google ranking.
What is page speed?
A plain-English explanation of what 'page speed' actually means.
Core Web Vitals explained
Google's three key speed measurements — and what they mean for you.
How to measure your site's speed
Free tools to check how fast your site is right now.
What slows sites down
What slows websites down
The most common causes of a slow site, ranked by impact.
Images & page speed
Why images are often the biggest culprit — and how to fix them.
How plugins affect speed
More plugins doesn't always mean more problems — but it can.
Fonts & page speed
How web fonts slow things down and what you can do about it.
Improving speed
Caching explained
How caching makes your site faster for returning visitors.
How a CDN speeds up your site
What a Content Delivery Network does and why it helps.
How hosting affects speed
Why your choice of host has a huge impact on performance.
Mobile performance explained
Why mobile speed is different — and why it matters more than ever.