Web Design12 October 2026 · 6 min read

Why your website is slow, and what it costs you

A letterpress type case filled with metal type, lit from the side

A slow website is not an aesthetic problem. On a phone, on a patchy signal, at eight on a Friday, it is the difference between an order and a closed tab, and the people who leave never tell you why.

Google measures this with three numbers, and they are worth knowing because they describe what the customer actually experiences rather than what a speed score says.

The three numbers

Largest Contentful Paint is how long until the main thing on the screen appears. The threshold is 2.5 seconds. On a menu page the main thing is usually a photograph, which is why menu photography is so often the culprit.
Interaction to Next Paint is how long the page takes to respond when somebody taps. The threshold is 200 milliseconds. This is the one people feel as "it’s laggy" without being able to say what is wrong.
Cumulative Layout Shift is how much the page moves about while it loads. The threshold is 0.1. It is the reason somebody taps "chips" and gets "cheese" because a banner loaded above it.

All three are measured at the 75th percentile of real visits, not in a lab, which means the slowest quarter of your customers decide your result.

What actually makes a takeaway site slow

Menu photographs straight off a phone. A 4MB image displayed two inches wide is the most common single cause, and resizing them is free.
Images with no declared size. The page cannot reserve the space, so everything jumps when they arrive. That is the layout shift number, and it is a five minute fix.
Third-party scripts. Chat widgets, pixels, review badges and cookie banners all run before your menu does. Each one is somebody else’s code deciding how fast your site is.
Everything loading at once. A menu with two hundred items that renders all of them, with photographs, before anybody can scroll.

How to check it honestly

Not on the shop wifi on a desktop. Open it on a phone, on mobile data, from the car park, the way a customer does. Then look at the field data in Search Console, which reports real visits rather than a laboratory test, and fix what it says rather than what a score out of a hundred says.

Speed is one of the few things on this site we can claim without hedging, because it is measurable on the day we hand it over and it stays measurable afterwards. It is part of how we build websites and ordering platforms, and it is one of the things an ongoing support arrangement is for: speed decays quietly as things get added.

Questions

Before you ask.

How fast should a takeaway website be?

The main content should appear within 2.5 seconds, a tap should respond within 200 milliseconds, and the layout should barely move while it loads. Those are Google’s Core Web Vitals thresholds, measured on real visits at the 75th percentile.

What usually makes a menu page slow?

Photographs straight off a phone at several megabytes each, images with no declared width and height, third-party scripts like chat widgets and review badges, and pages that render every item at once.

Does site speed affect Google rankings?

It is a real signal, but the bigger effect is commercial: on a phone on a patchy signal, a slow page is an abandoned order, and the people who leave never tell you why.

How should I test my own site?

On a phone, on mobile data, away from the shop wifi, the way a customer does. Then look at the field data in Search Console, which reports real visits rather than a laboratory score.

Why did a site that was fast get slow?

Things get added. A pixel here, a widget there, a batch of photographs uploaded at full size. Speed decays quietly, which is why it is worth checking on a schedule rather than once at launch.