What is Klaviyo?
Klaviyo is an Ecommerce email platform founded in 2012, headquartered in the United States. Starting at $20/mo, it targets Shopify and WooCommerce stores that segment on order and browsing data. Our verdict: Nothing else segments on ecommerce behaviour this well. Watch for: Price named in 51 of 148 recent excerpts, the highest rate we have measured. Rated 7.3/10 overall across ease of use, deliverability, and pricing value.
What is Klaviyo?
Klaviyo was built in Boston in 2012 by Andrew Bialecki and Ed Hallen, and it did not start as an email tool. The first product was a database that pulled orders, browsing and catalog data out of Shopify and WooCommerce stores into queryable customer profiles. Sending was added a year later, once it was clear the segments people built were useless without a way to message them.
That order of construction still shapes the product. The billable unit is the stored profile rather than the email, segments are live queries that re-evaluate as events arrive rather than static lists, and every profile carries fields Klaviyo computes from that store’s own transaction history: predicted date of next order, expected lifetime value and churn risk, each usable directly inside a flow condition.
Klaviyo has been public on the NYSE under KVYO since September 2023, and Shopify has held a stake since a $100 million investment in August 2022, a commercial relationship with the store platform that no competing ESP has. The company reports more than 205,000 paying customers and $937.5 million in 2024 revenue. Dollar Shave Club, ThirdLove, Hint Water and Montana Knife Company all run on it publicly.
There is no SMTP relay. Klaviyo sends through its own API and flows, so it replaces a marketing platform rather than a mail server.
Explore Klaviyo on SMTPedia
Frequently asked questions
Is Klaviyo worth it in 2026?
Our full editorial review covers pricing, deliverability, ease of use, support quality, and API/MCP maturity. Read the Klaviyo review →
How much does Klaviyo cost?
All pricing tiers, hidden fees, refund policy, and the true cost per email are broken down in the pricing tab. See Klaviyo pricing →
What are the best alternatives to Klaviyo?
Klaviyo compared with its closest competitors by use case, pricing, and switching cost. See alternatives →
What are the SMTP settings for Klaviyo?
Hostnames, ports, authentication, rate limits, and DKIM/SPF configuration for Klaviyo. See SMTP settings →
Does Klaviyo have an official MCP server?
Our API tab covers Klaviyo's REST API version, SDKs, rate limits, and MCP server support (official, community, and commercial wrappers). See API + MCP →
This review follows our email infrastructure testing methodology. We disclose affiliate relationships in our editorial independence policy.
