These two get compared a lot, but they answer different questions. The Google People API reads and writes contacts inside a user's Google account. ContactAPI stores your app's contacts in your own account.
At a glance
- Auth. The People API uses OAuth with sensitive scopes and verification; ContactAPI uses a bearer key.
- Where data lives. The People API keeps it in the user's Google account; ContactAPI keeps it in your database.
- Browser writes. The People API doesn't really do them; ContactAPI has publishable, domain-locked keys.
- AI access. ContactAPI ships an MCP server; the People API does not.
Use the People API when
Your feature is literally syncing the user's Google Contacts, such as a personal CRM, a contact importer, or an address-book integration.
Use ContactAPI when
You're collecting and managing contacts your product owns, like signups, waitlists, and form submissions, and want them in your own store with a simple REST contract.
Where ContactAPI fits
ContactAPI is an open-source REST API for saving and managing contacts. You POST an email plus any JSON fields, get simple CRUD back, and can reach the same data from an AI client over its MCP server. No CRM, no pipeline stages, no lock-in.