FullContact API for Identity Resolution and Data Enrichment

Overview

FullContact provides a suite of APIs designed to enrich customer and prospect data, facilitating identity resolution across various data points. The platform integrates with existing business systems to append publicly available information, creating more complete profiles of individuals and companies. This data enrichment process supports various business operations, including enhancing customer relationship management (CRM) systems, improving lead scoring models, and personalizing user experiences.

The core offerings include the FullContact Person API, which takes an email address, phone number, or social handle and returns detailed demographic, social, and professional information about an individual. Similarly, the FullContact Company API enriches company data using a domain name, providing firmographic details such as industry, size, and location. The FullContact Address API validates and standardizes physical addresses. These tools help businesses consolidate fragmented customer data into unified profiles, which can be critical for maintaining data accuracy and consistency across different departments.

For use cases such as lead scoring and qualification, FullContact's data can provide additional context beyond what's collected in initial forms, helping sales teams prioritize outreach more effectively. In customer experience, enriched profiles enable more targeted marketing campaigns and personalized product recommendations. The platform also contributes to fraud reduction by providing additional data points for identity verification, which can help flag suspicious activities or inaccurate information. FullContact was founded in 2010 and maintains compliance with data privacy regulations such as GDPR and CCPA, alongside SOC 2 Type II certification, addressing enterprise requirements for data security and privacy.

The developer experience is supported by well-organized documentation, clear API references, and code examples in multiple programming languages, including Python, Node.js, and Ruby. A developer portal provides access to API keys and usage metrics, streamlining the integration process for technical teams. This focus on developer enablement aims to reduce the time required to implement data enrichment capabilities into existing applications and workflows. For instance, a common implementation involves integrating the Person API within a CRM system to automatically update contact records with additional attributes upon creation or modification, ensuring that sales and marketing teams always have access to the most comprehensive customer view.

Key features

• Person API: Enriches individual profiles with demographic, social, and professional data using an email, phone number, or social ID. This helps build comprehensive customer views for personalization and lead qualification.
• Company API: Provides firmographic data, including industry, size, and location, based on a company's domain name. Useful for B2B sales intelligence and market segmentation.
• Address API: Validates, standardizes, and enriches physical address data, improving delivery rates and data quality.
• Identity Resolution: Matches disparate data points to create a unified profile for individuals, resolving identities across various sources to ensure data consistency.
• Data Compliance: Adheres to SOC 2 Type II, GDPR, and CCPA standards, providing frameworks for data security and privacy management.
• Developer SDKs: Supports integration with SDKs for Python, Node.js, Ruby, PHP, Java, and .NET, simplifying API consumption for various development environments.
• Usage Metrics: Provides a developer portal with access to API keys and real-time usage metrics, allowing for monitoring and management of API consumption.

Pricing

FullContact offers a tiered pricing structure, including a free developer plan and various paid options based on API call volume. Custom enterprise solutions are available for high-volume usage.

Pricing as of May 2026. For detailed and up-to-date pricing information, refer to the official FullContact pricing page.

Common integrations

FullContact's APIs can be integrated into various business applications and workflows to enhance data. Common integration points include:

• CRM Systems: Enriching contact and account records in platforms like Salesforce or HubSpot to provide sales and marketing teams with more comprehensive customer insights.
• Marketing Automation Platforms: Powering personalized email campaigns and targeted advertising by appending demographic and firmographic data to user profiles.
• Customer Data Platforms (CDPs): Contributing to a unified customer view by adding external data attributes to internal customer profiles.
• Fraud Detection Systems: Providing additional data points for identity verification to reduce fraudulent transactions and account creations.
• Lead Management Systems: Automating lead scoring and qualification by enriching new leads with relevant professional and company information.
• E-commerce Platforms: Personalizing product recommendations and improving customer segmentation based on enriched user profiles.

Alternatives

• Clearbit: Offers B2B data enrichment and lead intelligence, focusing on company and contact data for sales and marketing teams.
• ZoomInfo: Provides a comprehensive database of B2B contact and company information for sales, marketing, and recruiting.
• Apollo.io: Combines a B2B database with sales engagement tools, offering data enrichment alongside outreach automation.

Getting started

To begin using the FullContact API, you typically obtain an API key from your developer dashboard after signing up. The following Python example demonstrates how to make a basic request to the Person API to enrich an email address. This example uses the requests library for HTTP calls, which is a common approach in Python for interacting with RESTful APIs.

First, ensure you have the requests library installed:
pip install requests

Then, you can use the following Python code snippet:

import requests
import json

# Replace with your actual FullContact API key
API_KEY = "YOUR_FULLCONTACT_API_KEY"

# The email address to enrich
email_to_enrich = "[email protected]"

# FullContact Person API endpoint
url = "https://api.fullcontact.com/v3/person.enrich"

# Request headers including the API key
headers = {
    "Content-Type": "application/json",
    "Authorization": f"Bearer {API_KEY}"
}

# Request body with the email address
payload = {
    "email": email_to_enrich
}

try:
    response = requests.post(url, headers=headers, data=json.dumps(payload))
    response.raise_for_status() # Raise an exception for HTTP errors (4xx or 5xx)

    person_data = response.json()
    print(json.dumps(person_data, indent=2))

except requests.exceptions.HTTPError as http_err:
    print(f"HTTP error occurred: {http_err} - {response.text}")
except requests.exceptions.ConnectionError as conn_err:
    print(f"Connection error occurred: {conn_err}")
except requests.exceptions.Timeout as timeout_err:
    print(f"Timeout error occurred: {timeout_err}")
except requests.exceptions.RequestException as req_err:
    print(f"An unexpected error occurred: {req_err}")

This code sends a POST request to the FullContact Person API with an email address. The response, if successful, will contain a JSON object with enriched data related to that email. Error handling is included to catch common issues like network problems or API-specific errors. For more detailed examples and information on specific API endpoints, consult the FullContact API reference documentation.