@sindresorhus/is

Covers all JavaScript primitives, built-ins like Map/Set, typed arrays, and edge cases like async generators, which many libraries miss, as shown in the extensive API list.

Provides type guards that automatically narrow TypeScript types in conditional blocks and assertion methods that throw descriptive errors, improving type safety without extra boilerplate.

Named exports allow bundlers to include only the specific methods used, reducing bundle size for projects that import a subset of checks, as highlighted in the usage examples.

Avoids unreliable instanceof checks by designing methods to work correctly in iframes, workers, and other JavaScript environments, addressing a common pitfall mentioned in the FAQ.

Boasts millions of weekly downloads and is maintained by reputable developers, ensuring regular updates and reliability for production use.