Klaviyo IPO Presentation Deck

Select defined terms (cont'd) Dollar-Based Net Revenue Retention Rate: We calculate our Dollar-Based Net Revenue Retention rate, or NRR, by first identifying the cohort of customers as of twelve months prior to the date of determination. We then calculate the ARR from this customer cohort as of twelve months prior to the date of determination, or the Prior Period ARR, and the ARR from this customer cohort as of the date of determination, or the Current Period ARR. Current Period ARR includes any expansion, price increases, and customer subscriptions that are deactivated and subsequently reactivated during the applicable twelve-month period and reflects contraction or attrition over the last twelve months from this customer cohort, but excludes any ARR from new customers in the current period. We then divide the total Current Period ARR by the total Prior Period ARR to arrive at the point-in-time NRR. We then calculate the weighted average point-in-time NRR as of the last day of each month in the current trailing twelve-month period to arrive at the NRR, with the weightings determined by the total ARR at the end of each period. Klaviyo Attributed Value: We define Klaviyo Attributed Value, or KAV, as the amount of revenue our customers generated through orders placed by consumers within a specified period of time after a message is sent using our platform, which in the case of email is five days from when the message is sent, and in the case of SMS is twenty-four hours from when the message is sent. For email, the message also needs to be opened or clicked in order for the transaction to fall within our definition. KAV excludes orders placed with customers that do not opt-in to sharing data on placed orders, orders for which we cannot determine the currency or value, or unusual orders that appear to us to be anomalies. Since our definition of a customer does not include persons or entities that use our platform on a free trial basis, any revenue generated through orders placed with these persons or entities is also excluded from our definition of KAV. We do not net chargebacks or sales refunds from our calculation of KAV. If a customer leaves Klaviyo, we stop counting that customer's KAV after their last contracted month. KAV does not represent revenue earned by us and does not directly correlate to our revenue or results of operations. We use KAV as an internal estimate to track the value we drive to customers through our platform. Monthly Recurring Revenue: We define Monthly Recurring Revenue, or MRR, as the amount of revenue that we expect to receive in the next monthly period for our existing paid subscriptions, assuming no changes to such subscriptions in the next month. We measure MRR as a point-in-time calculation measured as of a particular date. MRR is a legal and contractual determination made by assessing the contractual terms of each paid subscription. MRR is not determined by reference to historical revenue, deferred revenue or any other U.S. GAAP financial measure over any period. It is forward looking and contractually derived as of the date of determination. 2023 Ⓒ Klaviyo Confidential 62

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