Klaviyo provides a software platform that helps consumer-facing businesses manage customer data and use it to drive marketing, customer service, and analytics. The core product is what Klaviyo calls a "B2C CRM" — a vertically integrated platform that stores unified consumer profiles and uses that data to power personalized outreach across email, SMS, WhatsApp, and push notifications. Most customers use Klaviyo for email and SMS marketing automation, sending targeted campaigns and automated message sequences triggered by real-time consumer behavior. Because Klaviyo's data layer and messaging infrastructure are integrated, businesses can segment audiences, personalize content, execute messages, and measure revenue attribution all within one platform. Klaviyo serves over 193,000 customers, from small businesses to enterprises like Unilever and Hershey, and started in eCommerce before expanding into restaurants, hospitality, fitness, and travel. Klaviyo generates revenue almost entirely through software subscriptions, priced on active consumer profiles stored and messages sent — not per seat — so revenue scales naturally as customers grow their databases and messaging volumes. The platform also includes a newer service product line with AI-powered chat, a customer self-service portal, and a helpdesk tool for human agents. Over 60% of ARR comes from multiproduct customers. Key growth levers include multiproduct cross-sell, international expansion (over one-third of revenue), and moving upmarket into mid-market and enterprise, where Klaviyo positions itself as a consolidation play against legacy marketing clouds like Salesforce and Adobe.