How to Create a JSON Server in Next.js (and Why You Might Want To)

Ever found yourself hacking together a frontend and just wishing you had an API to hit — without spinning up a full backend, setting up a database, or deploying some overkill Express app?

You’re not alone. Sometimes all you need is a mock API that speaks JSON. Good news? If you’re using Next.js, you’re already holding the keys to a lightweight, zero-config JSON server.

In this tutorial, we’ll walk through building a fake-but-functional JSON API inside a Next.js app. It’s quick, scalable-for-dev, and perfect for frontend prototyping, demos, MVPs, or even teaching.

Let’s get into it. 🛠️

Photo by Oskar Yildiz on Unsplash

Why Use Next.js as a JSON Server?

• Built-in API routes mean you get an Express-like backend with no extra setup.
• You control everything — structure, behavior, response shape.
• It’s serverless-ready (Vercel, anyone?).
• Ideal for frontend-focused devs who need API scaffolding.

This approach combines the convenience of JSON Server with the flexibility of real backend logic.

📦 Project Setup

Start fresh with a new Next.js app:

npx…