| MailChimp | 60,211 | https://mailchimp.com |
| Klaviyo | 48,306 | https://www.klaviyo.com/ |
| HubSpot | 46,993 | https://www.hubspot.com |
| OneSignal | 15,340 | https://onesignal.com |
| Constant Contact | 9,731 | https://www.constantcontact.com |
| ActiveCampaign | 5,843 | https://www.activecampaign.com |
| HighLevel | 5,790 | https://www.gohighlevel.com |
| MailerLite | 2,833 | https://www.mailerlite.com |
| RD Station | 2,784 | https://rdstation.com.br |
| Poptin | 2,474 | https://www.poptin.com |
| Sendinblue | 2,240 | https://www.sendinblue.com |
| Campaign Monitor | 2,169 | https://www.campaignmonitor.com |
| OptinMonster | 2,124 | https://optinmonster.com |
| ConvertKit | 1,823 | https://convertkit.com |
| Tolstoy | 1,114 | https://www.gotolstoy.com |
| 6sense | 1,010 | https://6sense.com |
| SendPulse | 854 | https://sendpulse.com |
| Birdeye | 741 | https://birdeye.com |
| Dreamdata | 725 | https://dreamdata.io |
| ManyChat | 683 | https://manychat.com/ |