Design system vs style guide: what is the difference, and which do you need?

The company has a website, a customer portal and an app. They were built at different times by different people, and it shows: three kinds of button, two nearly identical greens and a date written three ways. The brand manual is a PDF from 2019 that nobody opens. Every new feature starts with the same discussions about spacing and colours, and each time the answer is slightly different. That is exactly the problem style guides and design systems solve, but they solve it at different levels, and it is easy to buy too much or too little.

What is the difference between a design system and a style guide?

The simplest way to explain the difference is that a style guide is a recipe, and a design system is a kitchen with the recipe, the prepared ingredients and the tools. Both have value. A style guide makes sure your brand looks consistent. A design system makes sure your products are built consistently, faster and with fewer errors. The style guide is therefore a natural part of a design system and often the first step towards one.

What does a style guide for a website and app contain?

• Logo: variants, clear space, minimum size and use on dark and light backgrounds.
• Colours: primary, secondary and neutral colours with codes and their roles, such as "error" and "success".
• Typography: fonts, sizes, line heights and when each heading level is used.
• Spacing and grid: a fixed system, for example steps of 4 or 8 pixels, and columns on mobile and desktop.
• Icons and illustrations: style, stroke weight and where to get them.
• Images: subjects, cropping, colour tone and what to avoid.
• Buttons and links: primary, secondary and text link with states.
• Tone and language: form of address, glossary and examples of good microcopy.

The last point is often forgotten, even though it is what users notice most. A button can have the right colour and still say something confusing. We have collected the principles for interface copy in our guide to UX writing and microcopy, and a short language section belongs in every style guide.

What does a design system contain?

What separates a design system from a collection of nice components is the link between Figma and code. When a button in Figma and a button in code are built on the same tokens and share a name, designers can draw with the real building blocks, and developers can build without measuring pixels. How that link is made in practice is covered in from Figma to website.

When do you need a style guide, and when a design system?

What do a style guide and a design system cost?

A worked example: a 60-person company has a website, a customer portal and plans an app. Three suppliers have each built their part. A design system with tokens and 20 core components in Figma and React costs around DKK 200,000 in this example. In return, buttons, forms, tables and dialogs don’t have to be designed and built again for the app, and the portal’s next modules can be assembled from existing parts. When the same work would otherwise be done two or three times, the system typically pays for itself on the first major project. With only one website, the sums look different, and a style guide for around DKK 20,000 is the sensible choice. See more prices in what UX design costs.

How do you build a design system, step by step?

1. Take an inventory: screenshot every button, field, colour and heading in your current products.
2. Merge the duplicates: decide which of the five near-identical buttons is the right one.
3. Define tokens for colours, typography, spacing and radius, named by role.
4. Build the 10–15 most-used components in Figma and code at the same time.
5. Use them in a real project straight away, and adjust them based on what you learn.
6. Write short documentation per component: when, how and an example.
7. Appoint an owner and a set process for new components and changes.
8. Publish versions with a changelog, so teams know what is new.

Which design system mistakes and myths do we see?

• The system only lives in Figma: designers use it, developers build their own versions.
• Everything has to be in from the start: six months of work before the first product benefits.
• No owner: after a year, there are three versions of the same component again.
• Documentation nobody reads: 80 pages of text where short examples would do.
• Missing states: the components look great but have no error, focus or loading state.
• The brand changes without updating the tokens, so Figma and code drift apart.

Three myths we often hear

The first myth is that design systems are only for large companies. Company size matters less than the number of products and teams, and a mid-sized company with web, portal and app needs one more than a large company with one site. The second is that a design system makes everything uniform and dull. It removes repeated decisions, so designers can spend their time on the parts that are genuinely unique. The third is that it is a project with an end date. A design system is a product that lives as long as the solutions it is used in, and it needs time and an owner accordingly.

How do you keep a design system alive over time?

The most important thing is that the system is used every day, and that using it is easier than working around it. Set aside a small fixed time budget each month to fix bugs and add components teams have asked for. Keep Figma and code in sync with the same version numbers. Review the system once a year together with the brand and accessibility requirements. A neglected design system quickly turns into a form of technical debt, where old components live on in the code because nobody dares remove them.

How do we work with style guides and design systems at Ceptiv?

We always start with the smallest solution that solves your problem. For a single website, we create a style guide and a small set of tokens as part of the design. If you have several products, we build the design system alongside a real project, in Figma and in React and React Native at the same time, so it is tested from day one. Design and development sit in the same senior team, so there is no gap between drawing and code. Read more about our design system agency work, our branding services, or get a fixed price within 24 hours.