The WhatsApp Business Platform is Meta's set of business messaging APIs for WhatsApp, which has over 2 billion users. An API is an interface that another program calls over the internet. The platform is for medium and large businesses that message customers at scale from software; small businesses that answer customers by hand use the separate WhatsApp Business App.
A business connects directly, sending from its own phone number with its own developers, or onboards through a partner that handles the technical setup with little or no code. Messages fall into four categories: marketing (offers, abandoned cart reminders), utility (order confirmations, delivery updates), authentication (one-time passwords) and service (answers to customer questions, by an agent or an AI bot). Outgoing messages use approved templates and can carry interactive buttons, product lists, rich media and automated flows; webhooks deliver incoming messages to the business's system. When a user writes, a 24-hour customer service window opens. Developers get free test numbers, code samples and a sandbox.
Pricing is per delivered message, by the recipient's market and the message category. Service messages are free, and volume tiers lower the rates.