What are the recommended ways for static type checking?

Modern Recommendation (2026): TypeScript is the industry standard for type checking in React applications.

While PropTypes (React.PropTypes moved to prop-types package since React v15.5) are still available for runtime type checking, they have significant limitations:

• Only check types at runtime
• No compile-time errors
• Limited IDE autocomplete support
• No inference for complex types

TypeScript is now the recommended approach because it provides:

• Compile-time type checking
• Excellent IDE support with IntelliSense
• Type inference and generic types
• Better refactoring capabilities
• Growing ecosystem and community support

Note: Flow (Facebook's type checker) has seen declining adoption and is rarely used in new projects.

Example with TypeScript:

    interface UserProps {
      name: string;
      age: number;
      isActive?: boolean;
    }

    function User({ name, age, isActive = true }: UserProps) {
      return <div>{name} - {age}</div>;
    }