Typesafe Envs made Simple

The Next.js package comes preconfigured for Next.js and also enforces some extra rules by default to make sure you have out-of-the-box compatibility in all different Next.js runtimes.

For full documentation, see https://env.t3.gg

Installation

1# npm
2npm i @t3-oss/env-nextjs
3
4# pnpm
5pnpm add @t3-oss/env-nextjs
6
7# bun
8bun add @t3-oss/env-nextjs
9
10# deno
11deno add jsr:@t3-oss/env-nextjs

Usage

[!NOTE]

You may use any Standard Schema compliant validator of your choice. This example uses Zod

1// src/env.ts
2import { createEnv } from "@t3-oss/env-nextjs";
3import { z } from "zod";
4
5export const env = createEnv({
6  /*
7   * Serverside Environment variables, not available on the client.
8   * Will throw if you access these variables on the client.
9   */
10  server: {
11    DATABASE_URL: z.string().url(),
12    OPEN_AI_API_KEY: z.string().min(1),
13  },
14  /*
15   * Environment variables available on the client (and server).
16   *
17   * 💡 You'll get type errors if these are not prefixed with NEXT_PUBLIC_.
18   */
19  client: {
20    NEXT_PUBLIC_CLERK_PUBLISHABLE_KEY: z.string().min(1),
21  },
22  /*
23   * Specify what values should be validated by your schemas above.
24   * 
25   * If you're using Next.js < 13.4.4, you'll need to specify the runtimeEnv manually
26   * For Next.js >= 13.4.4, you can use the experimental__runtimeEnv option and
27   * only specify client-side variables.
28   */
29  runtimeEnv: {
30    DATABASE_URL: process.env.DATABASE_URL,
31    OPEN_AI_API_KEY: process.env.OPEN_AI_API_KEY,
32    NEXT_PUBLIC_PUBLISHABLE_KEY: process.env.NEXT_PUBLIC_PUBLISHABLE_KEY,
33  },
34  // experimental__runtimeEnv: {
35  //   NEXT_PUBLIC_PUBLISHABLE_KEY: process.env.NEXT_PUBLIC_PUBLISHABLE_KEY,
36  // }
37});