Does your website need a dark mode

A dark theme stopped being a niche feature for developer tools long ago — people expect it in almost any product. But "build a dark version" and "build one that actually works for the business" are different-sized jobs. Here's when dark mode is genuinely useful and when it's extra work with no noticeable effect.

Arguments for

• More comfortable to read in low light and over long sessions — particularly on text-heavy pages.

• It can have a positive effect on behavioural metrics — time on site and depth of browsing, which search engines take into account.

• Offering the choice signals attention to detail and makes the product read as modern and considered.

• It's especially worthwhile for information platforms and services with long content, where users spend a lot of time in one visit.

Arguments against

• There's no proven link between dark themes and eye health — the experience depends heavily on the individual and the lighting.

• Battery savings are mainly noticeable on OLED screens and barely register on ordinary LCD displays.

• In some sectors a dark theme works against the brand — medicine, wedding services and children's products are usually associated with a light, airy visual style.

• A good dark theme isn't an inversion of colours but separate design work: choosing contrast, adapting images, checking legibility.

When it's worth doing

A dark theme is justified for marketplaces and frequently-visited services, platforms with large volumes of content people read at length, corporate tools and dashboards, and products that deliberately position themselves as technical and modern.

When you can skip it

For single-page promo sites, an MVP at the start of a project, and sectors where a light, airy aesthetic carries meaning (children's products, say), a dark theme isn't a priority — especially early on, when development resources are limited.

Technical points that are easy to miss

• Don't use pure black (#000000) with pure white text — the contrast is too high and tires the eyes. A soft dark grey and a muted white are more comfortable.

• Images can't simply be colour-inverted — they need adapting separately for the dark theme.

• Use a slightly heavier font weight in dark mode — light thin text reads worse on a dark background.

• Test the dark theme on real devices — Windows, iOS and Android handle colour and screen brightness differently.

If you need to work out whether a dark theme is justified for your product, and how to implement it without hurting speed or legibility, get in touch.