JSON to Zod Schema & API Validator Generator

AI code assistants love writing route handlers that typecast JSON with as MyInterface with zero runtime checks. That crashes your database on unexpected inputs. Paste any JSON payload below to generate strict, production-ready Zod schemas.

Paste sample JSON request payload

Schema Variable Name

Include Next.js 15 App Router validation boilerplate

TypeScript Interfaces Disappear at Runtime

When you write const body = await req.json() as UserInput, TypeScript checks nothing at runtime. If a user passes an integer where a string was expected, or an empty string where an email was required, your server crashes.

Zod guarantees that malicious or corrupted requests are stopped at the door with a structured HTTP 400 error.

Generated Zod Schema & Handler

import { z } from 'zod';

export const createItemSchema = z.object({
  email: z.string().email().trim().toLowerCase(),
  fullName: z.string().min(1).max(255).trim(),
  websiteUrl: z.string().url(),
  planTier: z.string().min(1).max(255).trim(),
  seats: z.number().int().nonnegative(),
  isActive: z.boolean(),
  tags: z.array(z.string()),
});

export type CreateItemInput = z.infer<typeof createItemSchema>;

// Next.js 15 App Router API Route Handler Example:
import { NextResponse } from 'next/server';

export async function POST(req: Request) {
  try {
    const body = await req.json();
    const result = createItemSchema.safeParse(body);

    if (!result.success) {
      return NextResponse.json(
        {
          error: 'Validation failed',
          details: result.error.flatten().fieldErrors,
        },
        { status: 400 }
      );
    }

    const validatedData: CreateItemInput = result.data;
    // Proceed with database query using validatedData

    return NextResponse.json({ success: true, data: validatedData });
  } catch (error) {
    return NextResponse.json({ error: 'Invalid JSON payload' }, { status: 400 });
  }
}

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