Email list growth calculator. With 24-month projection chart.
Enter starting list size, monthly signups, and churn rate. Get net monthly growth, projected subscribers in 6/12/24 months, and the chart of compounding growth.
Starting list, signups, churn.
Net growth + projection.
Lists are compounding assets.
An email list at 4% net monthly growth doubles in 18 months and 4x's in 36. The owned-channel revenue compounds with it, since email RPM is largely list-size-bounded once flows are mature. The calculator above projects subscriber count month-by-month and computes the projected monthly email revenue at horizon. The chart shows the growth curve against the target line so you can see whether the signup rate is enough or whether the churn floor is the actual ceiling.
Three list-growth principles that compound. One, exit-intent popup with offer (3-7% conversion is a healthy Klaviyo benchmark; under 1.5% means the offer is weak or the trigger fires too aggressively). Two, churn discipline beats acquisition at scale — reducing churn from 1.5% to 0.8% on a 50K list saves 350 subscribers monthly, equivalent to acquiring 350 new signups, but at zero acquisition cost. Three, segment-then-broadcast — broadcasting promo content to the informational segment churns subscribers within 1-2 sends; segmentation discipline is the cheapest churn intervention.
Tools in the same cluster: LTV Calculator for the per-subscriber revenue view. Conversion Rate Calculator for the popup-to-list signup conversion. Runway Calculator for SaaS list-monetization horizon planning.
Six answers.
How is email list growth calculated?
Net monthly growth equals new subscribers minus churned subscribers. Churned subscribers include unsubscribes, hard bounces, and ESP-cleaned inactive emails. Compound growth over N months equals starting list multiplied by (1 + monthly net growth rate) to the Nth power, where net growth rate is (signups − churn) divided by current list size. The calculator projects this month-by-month so the curve is real, not the simplified compound-interest formula.
What signup and churn rates are typical in 2026?
DTC ecommerce: monthly signup rate 3-7% of list size (driven by site traffic and popup conversion); monthly churn 0.5-1.5%. Newsletter / content: monthly signup 1-3%; monthly churn 0.3-1%. SaaS marketing list: monthly signup 2-5%; monthly churn 0.8-2.5%. Engaged-segment lists (sub-90-day signup window) churn at one third the rate of full list. Klaviyo and Mailchimp benchmarks confirm these ranges; consult your ESP's deliverability dashboard for your exact churn.
Why does churn matter more than signup at scale?
At small lists, signups dominate growth. At larger lists, churn dominates. A 10,000-subscriber list with 500 monthly signups (5%) and 100 monthly churn (1%) grows by 400/month, +4% net. Scale that list to 100,000 with the same percentages: 5,000 signups and 1,000 churn, +4,000/month, still +4% net. But the absolute churn is 10x. Reducing churn from 1% to 0.6% saves 400 subscribers monthly, equivalent to acquiring an extra 400 signups. At 100K+ list size, churn reduction is usually the highest-impact growth lever.
What lifts signup and reduces churn?
Signup lifts: timed exit-intent popup with discount or content offer (3-7% conversion), embedded inline forms in high-traffic articles, social-media lead magnets, partner co-promotion. Churn reductions: tighten send cadence to 1-3 sends per week (overwhelmed lists churn 3x faster), segment by behavior (inactive 60-day re-engage flow), suppress non-openers from broadcast (boost opens, lower spam complaints). The biggest single churn driver is irrelevance — broadcasting promo to a list segmented as informational subscribers triggers unsubscribes within one or two sends.
How do I model a target list size?
Use the calculator to back into the signup rate needed. If target is 50,000 in 12 months from 12,000 starting list with 1% churn, monthly net growth must be roughly 12.5%. With 1% churn, that means 13.5% gross signup, or roughly 1,600 signups in month 1 ramping to 6,500 in month 12. Most brands cannot accelerate signup volume that fast without paid acquisition. The realistic target is usually 50-80% of the lift goal; use the projection chart to find the right balance of signup acceleration and churn reduction.
Does this tool save my data?
No. Every value lives in this browser tab only. Nothing is sent to any server. Closing the tab clears the data. The Copy Results button puts a plain-text summary on your clipboard.
List below target trajectory?
Our growth strategy engagements ship the Klaviyo / Mailchimp / Beehiiv flow stack, build the popup + lead-magnet acquisition layer, and tighten cadence to drop churn 30-50%.
Published .