customer.io vs mailman3.com

Market traction comparison · Updated Jul 2026

customer.io faviconcustomer.io
VS
mailman3.com faviconmailman3.com
 customer.iomailman3.comLeads
Monthly Visits725.7K654customer.io
Bounce Rate37.9%42.6%customer.io
SEO & Keywords520mailman3.com
Domain Age14y 10m11y 4mcustomer.io

customer.io leads in 3 of 4 dimensions, while mailman3.com leads in 1.

Growth Momentum

Growth Momentum
customer.iomailman3.com
 customer.iomailman3.comLeads
Monthly Visits725.7K654customer.io
MoM Change+17%-43%customer.io
Avg. Session6m49s1m24scustomer.io
Pages / Visit12.32.4customer.io

Growth Momentum · Insight

mailman3.com is losing traffic (-43%) despite 654 monthly visits. customer.io's +17% growth puts it on a trajectory to overtake.

Acquisition Strategy

 customer.iomailman3.comLeads
Primary ChannelDirect 76%
Bounce Rate37.9%42.6%customer.io
SEO & Keywords520mailman3.com
customer.io
Search 8%Direct 76%Social 4%Referral 5%Email 6%
SearchDirectSocialReferralPaidEmail
3
2
18
customer.io OnlySharedmailman3.com Only

Keyword Overlap Rate: 9%

Business Maturity

 customer.iomailman3.comLeads
Domain Age14y 10m11y 4mcustomer.io
RegisteredOct 2011Apr 2015
ExpiresOct 2026Apr 2027

Business Maturity · Insight

customer.io has been in the market for over a decade, indicating established presence.

Market Position

 customer.iomailman3.comLeads
Global Rank#41.0K#12.9Mcustomer.io
Category Rank#2.2K
PH Upvotes1440customer.io

Market Position · Insight

Each has untapped markets the other serves: customer.io could expand into Germany, France, while mailman3.com could target United States, United Kingdom, Canada.

Key Takeaways

  • mailman3.com is losing traffic (-43%) despite 654 monthly visits. customer.io's +17% growth puts it on a trajectory to overtake.
  • customer.io receives 1109.6x more monthly traffic than mailman3.com (725.7K vs 654).
  • customer.io is growing (+17%) while mailman3.com is declining (-43%).
  • customer.io keeps visitors significantly longer (6m49s avg session vs mailman3.com's 1m24s), suggesting deeper product engagement or stickier content.
  • With only 9% keyword overlap, they target largely different search audiences.
  • mailman3.com has 4.0x more ranking keywords (20 vs 5), indicating broader SEO footprint.

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Report based on data from July 2026