Careeroza

Type-only Imports

import type

import type { X } imports only a type. It is always removed from the JavaScript output, so it never causes a runtime import or a circular-dependency problem. You can also mark single names: import { type X, y }.

import type { Product } from "./models/product";      // erased completely
import { type Order, createOrder } from "./orders";   // Order erased, createOrder kept
export type { Product };                              // type-only re-export

verbatimModuleSyntax

With "verbatimModuleSyntax": true in tsconfig.json (recommended for new projects, used by Vite and many Next.js setups), TypeScript requires import type for types. The rule is simple: anything without type stays in the output, anything with type is removed.

{
  "compilerOptions": {
    "verbatimModuleSyntax": true
  }
}

Tip: ESLint rule @typescript-eslint/consistent-type-imports adds type automatically on save.

Using a Type-only Import as a Value

Example

A class imported with import type can be used in annotations, but not with new (TS1361).

import type { EventEmitter } from "node:events";

function attach(bus: EventEmitter): void {
  bus.on("x", () => {});
}

const bus = new EventEmitter();

Compiler output (tsc)

Line 7: error TS1361: 'EventEmitter' cannot be used as a value because it was imported using 'import type'.