Add forms to Next.js

Build with AI

Use our LLM-ready skills to integrate Forminit with your form for faster integration. Edit the example prompt with your needs and paste your Form ID. Your AI tool will handle the rest.

EXAMPLE PROMPT

Build me a contact form with name, email, and message fields. Connect it with Forminit for form submissions.

formId: <PASTE-YOUR-FORM-ID-HERE>

Use this integration skill guide: https://forminit.com/skills/forminit-nextjs/SKILL.md

Copy prompt

Next.js is a React framework that supports both static site generation (SSG) and server-side rendering (SSR). Forminit integrates seamlessly with Next.js through our NPM package, which provides a secure server-side proxy to protect your API keys.

What you’ll get:

• Accept form submissions without building a backend
• Email notifications for new submissions
• Spam protection (reCAPTCHA, hCaptcha, honeypot)
• File uploads support
• Submission dashboard to manage responses

Requirements:

• Next.js 13+
• Node.js 18+
• A Forminit account and Form ID

---

Quick Start

Step 1: Create a Form on Forminit

1. Sign up or log in at forminit.com
2. Create a new form
3. Go to Form Settings → Set authentication mode to Protected
4. Copy your Form ID (e.g., YOUR-FORM-ID)

Caution

Use Protected mode with Next.js. This allows you to use an API key securely on the server side for higher rate limits and better security.

---

Step 2: Install Forminit Package

npm install forminit

---

Step 3: Set Environment Variable

1. Create an API token from Account → API Tokens in your Forminit dashboard
2. Add the token to .env.local:

FORMINIT_API_KEY=sk_live_xxxxxxxxxxxx

Danger

Never expose API keys in client-side code or commit them to version control. Add .env.local to your .gitignore.

---

Step 4: Create API Route (App Router)

Create a proxy route that securely forwards requests to Forminit:

// app/api/forminit/route.ts

import { createForminitProxy } from 'forminit/next';

const forminit = createForminitProxy({
  apiKey: process.env.FORMINIT_API_KEY,
});

export const POST = forminit.POST;

---

Step 5: Create Form Component

// components/ContactForm.tsx

'use client';

import { useState, useRef } from 'react';
import { Forminit } from 'forminit';

const forminit = new Forminit({ proxyUrl: '/api/forminit' });

export function ContactForm() {
  const [status, setStatus] = useState<'idle' | 'loading' | 'success' | 'error'>('idle');
  const [errorMessage, setErrorMessage] = useState<string | null>(null);
  const formRef = useRef<HTMLFormElement>(null);

  async function handleSubmit(e: React.FormEvent<HTMLFormElement>) {
    e.preventDefault();
    setStatus('loading');
    setErrorMessage(null);

    const formData = new FormData(e.currentTarget);
    const { data, error } = await forminit.submit('Xk9mP2nQ1r', formData);

    if (error) {
      setStatus('error');
      setErrorMessage(error.message);
      return;
    }

    setStatus('success');
    formRef.current?.reset();
  }

  return (
    <form ref={formRef} onSubmit={handleSubmit}>
      <div className="form-group">
        <label htmlFor="firstName">First Name</label>
        <input
          type="text"
          id="firstName"
          name="fi-sender-firstName"
          placeholder="John"
          required
        />
      </div>

      <div className="form-group">
        <label htmlFor="lastName">Last Name</label>
        <input
          type="text"
          id="lastName"
          name="fi-sender-lastName"
          placeholder="Doe"
          required
        />
      </div>

      <div className="form-group">
        <label htmlFor="email">Email</label>
        <input
          type="email"
          id="email"
          name="fi-sender-email"
          placeholder="john@example.com"
          required
        />
      </div>

      <div className="form-group">
        <label htmlFor="message">Message</label>
        <textarea
          id="message"
          name="fi-text-message"
          placeholder="Your message..."
          rows={5}
          required
        />
      </div>

      {status === 'error' && (
        <p className="status-error">{errorMessage}</p>
      )}
      {status === 'success' && (
        <p className="status-success">Message sent successfully!</p>
      )}

      <button type="submit" disabled={status === 'loading'}>
        {status === 'loading' ? 'Sending...' : 'Send Message'}
      </button>
    </form>
  );
}

---

Step 6: Use in Your Page

// app/contact/page.tsx

import { ContactForm } from '@/components/ContactForm';

export default function ContactPage() {
  return (
    <div className="contact-page">
      <h1>Contact Us</h1>
      <p>We'd love to hear from you. Fill out the form below and we'll get back to you soon.</p>
      
      <ContactForm />
    </div>
  );
}

---

Using Environment Variables for Form ID

Store your Form ID in environment variables:

# .env.local

FORMINIT_API_KEY=sk_live_xxxxxxxxxxxx
NEXT_PUBLIC_FORMINIT_FORM_ID=Xk9mP2nQ1r

Access in your component:

const FORM_ID = process.env.NEXT_PUBLIC_FORMINIT_FORM_ID!;

const { data, error } = await forminit.submit(FORM_ID, formData);

Note

Use NEXT_PUBLIC_ prefix for variables that need to be accessible in client components.

---

Form Field Reference

For a complete list of available form blocks (text, email, phone, file, rating, select, etc.) and field naming patterns, see the Form Blocks documentation.

---

Complete Examples

Contact Form with Subject Selection

// components/ContactFormWithSubject.tsx

'use client';

import { useState, useRef } from 'react';
import { Forminit } from 'forminit';

const forminit = new Forminit({ proxyUrl: '/api/forminit' });

export function ContactFormWithSubject() {
  const [status, setStatus] = useState<'idle' | 'loading' | 'success' | 'error'>('idle');
  const [errorMessage, setErrorMessage] = useState<string | null>(null);
  const formRef = useRef<HTMLFormElement>(null);

  async function handleSubmit(e: React.FormEvent<HTMLFormElement>) {
    e.preventDefault();
    setStatus('loading');

    const formData = new FormData(e.currentTarget);
    const { error } = await forminit.submit('Xk9mP2nQ1r', formData);

    if (error) {
      setStatus('error');
      setErrorMessage(error.message);
      return;
    }

    setStatus('success');
    formRef.current?.reset();
  }

  return (
    <form ref={formRef} onSubmit={handleSubmit}>
      <input type="text" name="fi-sender-firstName" placeholder="First name" required />
      <input type="text" name="fi-sender-lastName" placeholder="Last name" required />
      <input type="email" name="fi-sender-email" placeholder="Email" required />
      
      <select name="fi-select-subject" required>
        <option value="">Select a subject</option>
        <option value="general">General Inquiry</option>
        <option value="support">Support</option>
        <option value="sales">Sales</option>
        <option value="partnership">Partnership</option>
      </select>
      
      <textarea name="fi-text-message" placeholder="Your message" required />
      
      {status === 'error' && <p className="status-error">{errorMessage}</p>}
      {status === 'success' && <p className="status-success">Message sent!</p>}
      
      <button type="submit" disabled={status === 'loading'}>
        {status === 'loading' ? 'Sending...' : 'Send'}
      </button>
    </form>
  );
}

Newsletter Signup

// components/NewsletterForm.tsx

'use client';

import { useState } from 'react';
import { Forminit } from 'forminit';

const forminit = new Forminit({ proxyUrl: '/api/forminit' });

export function NewsletterForm() {
  const [email, setEmail] = useState('');
  const [status, setStatus] = useState<'idle' | 'loading' | 'success' | 'error'>('idle');
  const [errorMessage, setErrorMessage] = useState<string | null>(null);

  async function handleSubmit(e: React.FormEvent) {
    e.preventDefault();
    setStatus('loading');

    const formData = new FormData();
    formData.append('fi-sender-email', email);

    const { error } = await forminit.submit('aB3cD5eF7g', formData);

    if (error) {
      setStatus('error');
      setErrorMessage(error.message);
      return;
    }

    setStatus('success');
    setEmail('');
  }

  return (
    <form onSubmit={handleSubmit} className="newsletter-form">
      <input
        type="email"
        value={email}
        onChange={(e) => setEmail(e.target.value)}
        placeholder="Enter your email"
        required
      />
      <button type="submit" disabled={status === 'loading'}>
        {status === 'loading' ? 'Subscribing...' : 'Subscribe'}
      </button>
      
      {status === 'error' && <p className="status-error">{errorMessage}</p>}
      {status === 'success' && <p className="status-success">Thank you for subscribing!</p>}
    </form>
  );
}

Feedback Form with Rating

// components/FeedbackForm.tsx

'use client';

import { useState, useRef } from 'react';
import { Forminit } from 'forminit';

const forminit = new Forminit({ proxyUrl: '/api/forminit' });

export function FeedbackForm() {
  const [rating, setRating] = useState<number | null>(null);
  const [status, setStatus] = useState<'idle' | 'loading' | 'success' | 'error'>('idle');
  const [errorMessage, setErrorMessage] = useState<string | null>(null);
  const formRef = useRef<HTMLFormElement>(null);

  async function handleSubmit(e: React.FormEvent<HTMLFormElement>) {
    e.preventDefault();
    setStatus('loading');

    const formData = new FormData(e.currentTarget);
    const { error } = await forminit.submit('Xk9mP2nQ1r', formData);

    if (error) {
      setStatus('error');
      setErrorMessage(error.message);
      return;
    }

    setStatus('success');
    formRef.current?.reset();
    setRating(null);
  }

  return (
    <form ref={formRef} onSubmit={handleSubmit}>
      <input type="email" name="fi-sender-email" placeholder="Email (optional)" />
      
      <fieldset>
        <legend>How would you rate your experience?</legend>
        {[1, 2, 3, 4, 5].map((n) => (
          <label key={n}>
            <input
              type="radio"
              name="fi-rating-experience"
              value={n}
              checked={rating === n}
              onChange={() => setRating(n)}
            />
            {n}
          </label>
        ))}
      </fieldset>
      
      <textarea name="fi-text-feedback" placeholder="Tell us more (optional)" />
      
      {status === 'error' && <p className="status-error">{errorMessage}</p>}
      {status === 'success' && <p className="status-success">Thank you for your feedback!</p>}
      
      <button type="submit" disabled={status === 'loading'}>
        {status === 'loading' ? 'Submitting...' : 'Submit Feedback'}
      </button>
    </form>
  );
}

Job Application with File Upload

// components/ApplicationForm.tsx

'use client';

import { useState, useRef } from 'react';
import { Forminit } from 'forminit';

const forminit = new Forminit({ proxyUrl: '/api/forminit' });

export function ApplicationForm() {
  const [status, setStatus] = useState<'idle' | 'loading' | 'success' | 'error'>('idle');
  const [errorMessage, setErrorMessage] = useState<string | null>(null);
  const formRef = useRef<HTMLFormElement>(null);

  async function handleSubmit(e: React.FormEvent<HTMLFormElement>) {
    e.preventDefault();
    setStatus('loading');

    const formData = new FormData(e.currentTarget);
    const { error } = await forminit.submit('T4vWx8yZ0q', formData);

    if (error) {
      setStatus('error');
      setErrorMessage(error.message);
      return;
    }

    setStatus('success');
    formRef.current?.reset();
  }

  return (
    <form ref={formRef} onSubmit={handleSubmit}>
      <input type="text" name="fi-sender-firstName" placeholder="First name" required />
      <input type="text" name="fi-sender-lastName" placeholder="Last name" required />
      <input type="email" name="fi-sender-email" placeholder="Email" required />
      <input type="tel" name="fi-sender-phone" placeholder="Phone (+1234567890)" />
      
      <input type="url" name="fi-url-linkedin" placeholder="LinkedIn profile URL" />
      <input type="url" name="fi-url-portfolio" placeholder="Portfolio URL" />
      
      <select name="fi-select-position" required>
        <option value="">Select position</option>
        <option value="frontend">Frontend Developer</option>
        <option value="backend">Backend Developer</option>
        <option value="fullstack">Full Stack Developer</option>
        <option value="designer">UI/UX Designer</option>
      </select>
      
      <label>
        Resume (PDF)
        <input type="file" name="fi-file-resume" accept=".pdf" required />
      </label>
      
      <label>
        Cover Letter (optional)
        <input type="file" name="fi-file-cover_letter" accept=".pdf,.doc,.docx" />
      </label>
      
      <textarea name="fi-text-why_join" placeholder="Why do you want to join us?" />
      
      {status === 'error' && <p className="status-error">{errorMessage}</p>}
      {status === 'success' && <p className="status-success">Application submitted!</p>}
      
      <button type="submit" disabled={status === 'loading'}>
        {status === 'loading' ? 'Submitting...' : 'Submit Application'}
      </button>
    </form>
  );
}

---

JSON Submission (Alternative)

Instead of FormData, you can submit structured JSON:

const { data, error } = await forminit.submit('Xk9mP2nQ1r', {
  blocks: [
    {
      type: 'sender',
      properties: {
        email: 'john@example.com',
        firstName: 'John',
        lastName: 'Doe',
      },
    },
    {
      type: 'text',
      name: 'message',
      value: 'Hello world',
    },
    {
      type: 'select',
      name: 'subject',
      value: 'general',
    },
  ],
});

Note

JSON submission does not support file uploads. Use FormData for forms with file inputs.

---

Handling Form Submission Response

The SDK returns { data, redirectUrl, error }:

On success:

{
  data: {
    hashId: "7LMIBoYY74JOCp1k",      // Unique submission ID
    date: "2026-01-01 21:10:24",      // Timestamp
    blocks: {                          // Submitted values
      sender: {
        firstName: "John",
        lastName: "Doe",
        email: "john@example.com"
      },
      message: "Hello from Next.js!"
    }
  },
  redirectUrl: "https://forminit.com/thank-you"
}

On error:

{
  error: {
    error: "ERROR_CODE",
    code: 400,
    message: "Human-readable error message"
  }
}

---

Redirect After Submission

If you prefer to redirect users to a thank-you page:

import { useRouter } from 'next/navigation';

export function ContactForm() {
  const router = useRouter();
  
  async function handleSubmit(e: React.FormEvent<HTMLFormElement>) {
    e.preventDefault();
    
    const formData = new FormData(e.currentTarget);
    const { data, redirectUrl, error } = await forminit.submit(FORM_ID, formData);

    if (error) {
      setStatus('error');
      setErrorMessage(error.message);
      return;
    }

    // Redirect to thank-you page
    router.push('/thank-you');
    // Or use Forminit's redirect URL:
    // window.location.href = redirectUrl;
  }
  
  // ...
}

Create a thank-you page:

// app/thank-you/page.tsx

import Link from 'next/link';

export default function ThankYouPage() {
  return (
    <div>
      <h1>Thank You!</h1>
      <p>Thank you for your message! We'll get back to you soon.</p>
      <Link href="/">← Back to Home</Link>
    </div>
  );
}

---

Project Structure Example

Here’s a typical Next.js project structure with Forminit forms:

my-nextjs-app/
├── app/
│   ├── api/
│   │   └── forminit/
│   │       └── route.ts           # Forminit proxy route
│   ├── contact/
│   │   └── page.tsx               # Contact page
│   ├── thank-you/
│   │   └── page.tsx               # Thank you page
│   ├── layout.tsx                 # Root layout
│   └── page.tsx                   # Homepage
├── components/
│   ├── ContactForm.tsx            # Contact form component
│   ├── NewsletterForm.tsx         # Newsletter component
│   └── FeedbackForm.tsx           # Feedback component
├── .env.local                     # Environment variables
├── next.config.js                 # Next.js config
├── package.json
└── tsconfig.json

---

TypeScript Types

The Forminit SDK includes TypeScript definitions:

import type { ForminitResponse, ForminitError } from 'forminit';

const { data, redirectUrl, error }: ForminitResponse = await forminit.submit(
  formId,
  formData
);

if (error) {
  const typedError: ForminitError = error;
  console.error(typedError.code, typedError.message);
}

---

Next Steps

1. View your submissions in the Forminit dashboard
2. Set up email notifications for new submissions
3. Explore webhook integrations for advanced workflows