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Email Append API

Email AppendAPI

Append verified email addresses using name and address data. High-quality consumer intelligence with confidence scoring and compliance-friendly enrichment workflows.

High Quality

Match Accuracy

10 tokens

Per Request

Datazapp

Data Source

Complete Email Enrichment Platform

Multi-field matching for maximum accuracy and confidence

Verified Consumer Intelligence

Matches against premium consumer databases with confidence scoring for each appended email. Uses Datazapp contact intelligence for maximum accuracy.

High-quality matches
Confidence scoring
Consumer database
Premium intelligence

Address-Normalized Matching

Cleans and normalizes address inputs to improve match rates across fragmented data sources. Handles variations in street names, abbreviations, and formatting.

Address normalization
Format handling
Fuzzy matching
Improved accuracy

Multi-Field Confidence

Uses name, street, city, and ZIP signals to return the highest-confidence email for each record. Multiple data points ensure reliable enrichment.

Multi-field matching
Signal aggregation
Best-match selection
Quality indicators

Quality Insights & Reporting

Get quality indicators and match explanations to decide when to trust or review appended data. Transparent match reasoning for compliance.

Match explanations
Quality scores
Review flags
Audit trails

Email Append Use Cases & Results

Real businesses achieving measurable improvements with email enrichment

Lead Enrichment & Nurture

Fill missing emails on inbound leads to trigger nurture sequences faster. Improve contactability and accelerate pipeline velocity.

35% more contacts
  • Faster nurture activation
  • Improved contactability
  • Pipeline acceleration
  • Lead scoring boost

CRM Hygiene & Backfill

Backfill missing emails in legacy CRMs and keep sales, support, and billing teams aligned on best contacts for each account.

40% data completion
  • Legacy data recovery
  • Team alignment
  • Complete records
  • Better segmentation

Outbound Personalization

Identify the best email per contact for outbound programs while preserving deliverability and sender reputation.

25% better delivery
  • Optimal email selection
  • Deliverability focus
  • Sender protection
  • Campaign optimization

Customer 360 & Identity

Build complete customer profiles by appending verified emails across touchpoints. Unify records and enhance identity resolution.

50% profile completion
  • Profile completion
  • Identity resolution
  • Cross-channel unification
  • Better personalization

Why Choose 1Lookup Email Append?

Premium data quality with transparent pricing

Premium Consumer Database

Access to Datazapp consumer intelligence with billions of records and regular updates

Confidence Scoring

Every match includes quality indicators so you know which results to trust immediately

Address Normalization

Built-in address cleaning improves match rates without preprocessing on your end

Transparent Pricing

Simple token-based pricing at 10 tokens per request with no hidden fees

Simple Email Append Integration

Enrich contacts with a single API call

POST /api/lookup
// Email append from name and address
const response = await fetch('https://api.1lookup.io/api/lookup', {
  method: 'POST',
  headers: {
    'Authorization': 'Bearer YOUR_API_KEY',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    type: 'email-append',
    firstName: 'Jane',
    lastName: 'Smith',
    address: '123 Main Street',
    city: 'Austin',
    zip: '78701'
  })
})

// Response
{
  "success": true,
  "email": "jane.smith@example.com",
  "confidence": 0.85,
  "match_type": "exact",
  "tokens_used": 10
}

Email Append API FAQ

Common questions about our email enrichment service

Our email append API requires first name, last name, street address, city, and ZIP code. The more accurate your input data, the higher the match rate and confidence score.

Match rates vary based on input quality, but typically range from 30-60% for consumer records. Each result includes a confidence score to help you decide which emails to use immediately vs. review.

Email append returns the best-matching email from our consumer database. We recommend pairing with our Email Validation API to verify deliverability before sending.

Email validation checks if an existing email is deliverable. Email append finds an email address when you only have name and address information. They complement each other in a complete data enrichment workflow.

If no match is found, the API returns a no-match response. You are still charged for the lookup attempt as the database search was performed.

Our data is sourced from compliant consumer databases. However, you are responsible for ensuring your use case complies with applicable laws like CAN-SPAM, GDPR, and CCPA.

Technical Specifications

Token Cost

10 tokens

Data Source

Datazapp

Match Rate

30-60%

Input Fields

5 required

Confidence

Included

Response

Real-time

Start Enriching Contacts Today

Append verified emails to your contact database with confidence scoring and quality indicators

100 free credits • Setup in 5 minutes • Premium support