OOPSpam vs Customer.io Comparison (2025)

What are the differences between OOPSpam and Customer.io?

Forward Email Team
Written by
Forward Email TeamVerified
Published
7/1/25
Time to read
Less than 5 minutes
We recommend Forward Email as the best alternative to OOPSpam.

Email Service Comparison

20 facts in comparison
OOPSpamvs.Customer.io

OOPSpam

Automate your Spam and Abuse Detection
"Automate your Spam and Abuse Detection"
  • Hardenize Test
  • Internet.nl Site Test
  • Internet.nl Mail Test
  • Mozilla HTTP Observatory Grade
  • Qualys SSL Labs SSL Server Test
vs.

Customer.io

Send messages people actually want to receive using real-time customer data
"Send messages people actually want to receive using real-time customer data"
  • Hardenize Test
  • Internet.nl Site Test
  • Internet.nl Mail Test
  • Mozilla HTTP Observatory Grade
  • Qualys SSL Labs SSL Server Test
$49/moPricing$100/mo
Requires 3rd partyStorageNo Customer.io does not support storage
UnknownAttachments2 MB
NoOpen-SourceNo
NoSandboxed Encryption No
NoUnlimited DomainsNo
NoUnlimited AliasesNo
NoTTI No
❌ Requires 3rd partySMTPYes
❌ Requires 3rd partyIMAPNo
❌ Requires 3rd partyPOP3No
YesAPIYes
NoE2EE No
NoOpenPGP No
NoWKD No

Email Service Screenshots

Closed-source

OOPSpam

OOPSpam is a closed-source email service. Their official description reads: Automate your Spam and Abuse Detection

OOPSpam is a closed-source email service.
Photograph by Forward Email
Visit Website
Closed-source

Customer.io

Customer.io is a closed-source email service. Their website says: Send messages people actually want to receive using real-time customer data

Customer.io is a closed-source email service.
Photo by Forward Email
Visit Website

Compare OOPSpam with 78 email services