Common breakpoints in web design refer to specific screen sizes where a website layout adjusts for better user experience. These breakpoints ensure responsive design across devices like mobile, tablet, and desktop. Typical breakpoints include widths such as 320px, 768px, 1024px, and 1200px. By using proper breakpoints, designers ensure that content looks clean and functions smoothly on all screen sizes. This improves usability, accessibility, and overall website performance.