Easy to Use APIs, Designed for Developers - Lob

12,000+ innovative companies choose Lob to ignite possibilities. Meet our customers.

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Powerful APIs built for scale

Lob’s Print & Mail APIs and Address Verification APIs allow you to easily integrate offline communications into your apps, internal systems, or marketing stack. Flexible scalability allows you to send 100 or 100 million mailpieces in minutes.

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Transform outdated,
manual processes with
Lob’s easy-to-integrate APIs

Integrate with RESTful APIs to streamline workflows for direct mail, address data, and identity verification at scale
Trigger postcards, self mailers, letters, and checks on demand directly from your CRM or custom applications
Leverage Lob's scalable on-demand Print Delivery Network to create and send mailpieces more efficiently

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Hyper-personalize content programmatically

Connect to sources of customer data including marketing automation platforms and CRMs to tailor messaging for each individual
Update dynamic content with HTML templates and merge variables
Include offer codes, unique URLs, or QR codes to track ROI

Get visibility in every step of the direct mail process

Track every mailpiece with powerful webhooks
Report on real-time and historic mail statuses for compliance audits

Meet compliance requirements with smart webhooks

Our industry-leading security is trusted by Fortune 500 companies and is built into every aspect of Lob.

SOC 2 Type 2 and HIPAA, and GDPR compliant
Signed webhooks with HMAC signatures
Protect personal data with end-to-end encryption and scheduled deletion
Report on real-time and historic mail statuses for compliance audits

Modern SaaS technology

Modern SDKs in programming languages like PHP, Python, Ruby, Java, Elixir, TypeScript, and C#/.NET
Explore Lob APIs with REST clients (Postman and Insomnia)
UI libraries and components in JavaScript frameworks like React & Vue
Integrate through low-code, no-code solutions like Zapier and Make, or popular marketing & workflow automation tools like Salesforce, Braze, Iterable, and Hubspot

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Start exploring Lob APIs with Postman

This workspace provides sophisticated tools for developers, while also enabling you to interact with our APIs without writing any code.

7 Intriguing Ways to Use Address Verification

Address verification fosters trust in businesses, inform business decisions, facilitate crucial business processes, and enable efficient service delivery

Using Lob with C# and Flurl

We dive into C# to show how to easily implement Lob’s API in your ASP.Core application using the Flurl Http Library.

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