Lead Validator | APIVerve API Tutorial

A powerful lead validation tool built with Next.js 14. Verify email addresses and phone numbers to qualify leads with a beautiful, modern UI and quality scoring.

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Features

• Email validation (format, deliverability, disposable detection)
• Phone number validation with carrier lookup
• Multi-country phone support (10+ countries)
• Lead quality score calculation
• Beautiful glassmorphism UI design
• Server-side API integration (secure)
• Real-time validation feedback
• Responsive mobile design

Quick Start

1. Clone this repository

   git clone https://github.com/apiverve/lead-validator-nextjs-tutorial.git
   cd lead-validator-nextjs-tutorial

2. Install dependencies

   npm install

3. Add your API key

   Open app/api/validate/route.js and replace the placeholder:

   const API_KEY = 'your-api-key-here';

4. Start the development server

   npm run dev

5. Open in browser

   Navigate to http://localhost:3000

Project Structure

lead-validator-nextjs-tutorial/
├── app/
│   ├── api/
│   │   └── validate/
│   │       └── route.js     # API route for validation
│   ├── globals.css          # Global styles
│   ├── layout.js            # Root layout
│   ├── page.js              # Main page component
│   └── page.module.css      # Page styles
├── package.json             # Dependencies
├── next.config.js           # Next.js configuration
├── screenshot.jpg           # Preview image
├── LICENSE                  # MIT license
├── .gitignore               # Git ignore rules
└── README.md                # This file

How It Works

1. User enters lead info - Email and/or phone number
2. Form submission - Data sent to API route
3. Parallel validation - Email and phone validated simultaneously
4. Score calculation - Quality score computed from results
5. Results display - Visual feedback with detailed breakdown

The API Calls

// Email Validation
const emailResponse = await fetch(
  `${EMAIL_API}?email=${encodeURIComponent(email)}`,
  { headers: { 'x-api-key': API_KEY } }
);

// Phone Validation
const phoneResponse = await fetch(
  `${PHONE_API}?number=${encodeURIComponent(phone)}&country=${country}`,
  { headers: { 'x-api-key': API_KEY } }
);

API Reference

Email Validator

Endpoint: GET https://api.apiverve.com/v1/emailvalidator

Query Parameters:

Parameter	Type	Required	Description
email	string	Yes	Email address to validate

Example Response:

{
  "status": "ok",
  "data": {
    "valid": true,
    "email": "[email protected]",
    "domain": "example.com",
    "isDisposable": false
  }
}

Phone Number Validator

Endpoint: GET https://api.apiverve.com/v1/phonenumbervalidator

Query Parameters:

Parameter	Type	Required	Description
number	string	Yes	Phone number to validate
country	string	No	ISO country code (e.g., "US")

Example Response:

{
  "status": "ok",
  "data": {
    "valid": true,
    "formatted": "+1 555-123-4567",
    "type": "mobile",
    "carrier": "Verizon"
  }
}

Lead Quality Scoring

The lead quality score is calculated based on:

Criteria	Impact
Valid email format	+50%
Non-disposable email	+25% (included in email)
Valid phone number	+50%

Score Interpretation:

• 80-100: High quality lead - prioritize outreach
• 50-79: Medium quality - verify manually
• 0-49: Low quality - requires review

Use Cases

Lead validation is essential for:

• Sales Teams - Qualify leads before outreach
• Marketing - Clean email lists for campaigns
• SaaS Signups - Verify new user registrations
• E-commerce - Validate checkout information
• CRM Integration - Enrich contact data
• Lead Generation - Filter low-quality submissions

Customization Ideas

• Add bulk validation for CSV uploads
• Integrate with HubSpot, Salesforce, or other CRMs
• Add more validation fields (address, company)
• Create webhook notifications for new leads
• Add lead scoring based on custom criteria
• Export validation reports

Tech Stack

• Next.js 14 - React framework with App Router
• React 18 - UI library
• CSS Modules - Scoped styling

Related APIs

Explore more APIs at APIVerve:

• Email Validator - Validate email addresses
• Phone Number Validator - Validate phone numbers
• Email Disposable Checker - Detect disposable emails

License

MIT - see LICENSE

Links

• Get API Key - Sign up free
• APIVerve Marketplace - Browse 300+ APIs
• Email Validator API - API details