What is Utility Class?
A single CSS class that does exactly one thing, like `font-bold`, `mt-4`, or `flex`. You combine many utility classes to build a full style without writing custom CSS.
flex · p-4 · font-bold → styled
A utility class does...
Write it in your own words in the app.
In real work
Use only utility classes. No wrapper classes or custom CSS. Compose layout with flex, gap, and padding utilities.
In the illustration
Each stamp presses the card in turn and adds exactly one effect: flex lines the parts up in a row, p-4 pushes in padding, font-bold thickens the label. Three small stamps, one finished style.
Replace the custom .stack-md rule in your component library with the matching utility class names, and remove the stylesheet if nothing else uses it.
Try it now
The fastest way to learn a word is to use it. Open this line in the agent you already work in and watch what it does. Change the tool to the one you use.
Go further
01Practice
Make it stick
One term a day, a short quiz, and sentence practice that checks your own words.
02Verify
Prove you know it
Pass the quiz and keep it in a Skills Wallet you can share with anyone who needs proof.
03Career
Find the work that uses it
See which roles lean on this vocabulary, and what they pay in year one.
Learn the next term tomorrow.
Google gives a definition. Prompthaus pairs each term with how it shows up in standups, PRs, prompts, and design reviews. Then it quizzes you until the word sticks. One term a day on iPhone.
