JSON to TypeScript Interfaces

Yes. The generator recursively traverses all nested objects and arrays, creating a separate named interface for each one — so you get clean, reusable types rather than deeply nested inline types.

When 'Make nullable fields optional' is on, null fields are typed as 'string | null' with a '?' modifier. When off, null fields are typed as 'null' — useful when you want to be strict about what's truly unknown.

In TypeScript, interfaces are open (can be extended/merged) while type aliases are closed. For most API response shapes, both are equivalent. Use interface for domain models you might extend; use type for strict data shapes.

Yes. If you paste an array like [{...}, {...}], the generator creates interfaces for the item type and exports a root type alias like 'type Users = User[]'.