What is the difference between my Secret and Publishable API Keys?
Secret keys: Your account's secret API keys can perform any API request to Lob without restriction. These keys should be kept confidential and only stored on your own servers.
Publishable keys: These keys are limited to US verifications, international verifications, and US autocomplete requests. While we encourage you to use a secret key for maximum security, you can publish these keys to JavaScript code or in an Android or iPhone app without exposing print and mail services or your secret key.