Free tool
Email list growth rate calculator
The short answer
List growth rate is (new subscribers - unsubscribes - bounces - spam complaints) / subscribers at the start, times 100. A list of 8,000 that adds 520 and loses 154 grows 366, or 4.6% for the month. Held at that rate for a year, it would reach about 13,700; in practice signups follow traffic, so treat the projection as a ceiling.
On this page 6 sections
Email list growth
Net growth rate (month)
4.58%
Net change
+366
Monthly loss rate
1.93%
List in 12 months
13,684
The list grows about 4.58% a month after losses. The projection assumes the same rate every month; new signups usually track traffic, so treat it as a ceiling, not a forecast.
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The formulas
- Net change = new subscribers - unsubscribes - hard bounces removed - spam complaints.
- Net growth rate = net change / subscribers at the start of the month.
- Monthly loss rate = (unsubscribes + bounces + complaints) / subscribers at the start.
- Projection = list x (1 + monthly growth rate)^months, assuming the rate holds.
Worked example
A newsletter starts the month with 8,000 subscribers, adds 520, and loses 90 to unsubscribes, 60 to hard bounces and 4 to spam complaints. Net change is +366, a 4.6% growth rate, with a 1.9% monthly loss rate. Twelve months at 4.6% compounds to about 13,700.
Reading it
- Loss rate matters as much as signups. A list adding 5% a month and losing 4% is barely growing. Unsubscribe spikes after a send usually point at frequency or relevance, not the list.
- Bounces are a quality signal. A rising hard-bounce rate means bad addresses are getting in at signup. Double opt-in or verification at the form fixes it; Bouncer checks addresses in bulk.
- Complaints put delivery at risk. Google's email sender guidelines ask senders to keep the spam rate shown in Postmaster Tools below 0.3% and aim for under 0.1%.
- Inactive subscribers are not growth. Many lists carry a third or more who never open. Removing them shrinks the list but usually improves inbox placement. See email marketing metrics.
Email platforms that report growth, unsubscribes and engagement by signup source are compared in the best email marketing analytics tools; see also the Sender and GetResponse profiles. For click-through on sends, use the CTR calculator.
Questions
- How do you calculate email list growth rate?
- Subtract unsubscribes, hard bounces and spam complaints from new subscribers, then divide by the list size at the start of the period. 520 new minus 154 lost on a list of 8,000 is 366 / 8,000 = 4.6% for the month.
- Should bounces count against list growth?
- Yes. Hard-bounced addresses cannot receive email and should be removed, so they reduce the list you can actually reach. Counting only signups and unsubscribes overstates growth.
- What spam complaint rate is too high?
- Google's sender guidelines ask senders to keep the spam rate reported in Postmaster Tools below 0.3% and to aim for below 0.1%. Above that, more of your mail is filtered to spam.
Sources
Related guides
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