What your host actually controls, what your site controls, and where to focus first.
Site speed comes from two separate places: your hosting infrastructure (server response time, resource limits, CDN availability) and your site itself (image sizes, unused code, number of requests). Fixing the wrong one wastes money — here's how to tell which is your bottleneck.
Before touching your site's code, run a PageSpeed Insights test and look at "Time to First Byte" (TTFB). A high TTFB on a lightweight page usually means the hosting tier itself is the bottleneck, not your content.
Upgrading hosting won't fix a bloated page, but it will fix: slow TTFB caused by resource contention on shared hosting, lack of HTTP/2 or HTTP/3 support, and no built-in caching layer. If you've already optimized the site itself and speed is still poor, the hosting tier is genuinely the limit.
Run the PageSpeed test above first — it tells you which half of the problem you actually have.