Dev tools · alternatives · 2026

24 alternatives to FourTwenty Email Service

Secure API for forms with recipient-bound keys & geoblocking

Below are 24 products that do a similar job, ranked by how close each is in meaning and then by launch-day votes.

1. 1
   Resend▲1,325

   Email for developers

   2023 · resend.com · its alternatives →

2. 2
   Blocks▲715

   AI-powered builder to create your emails

   2023 · useblocks.io · its alternatives →

3. 3IM
   I made an open-source anonymous email forwarding service▲393

   2019 · anonaddy.com · its alternatives →

4. 4
   Mailmodo Email API▲244

   APIs to send automated interactive emails with forms

   2021 · its alternatives →

5. 5
   TrustyMails▲78

   Free API to block disposable emails - say goodbye to fraud

   2023 · its alternatives →

6. 6
   Warmy.io▲417

   Boost your email deliverability with an AI driven algorithm

   2024 · its alternatives →

7. 7
   ProxiedMail▲170

   Email forwarding with unlimited mailboxes

   2024 · proxiedmail.com · its alternatives →

8. 8
   Unosend▲205

   Send transactional + marketing email w/ 99.9% deliverability

   Dec 2025 · unosend.co · its alternatives →

9. 9
   MailAdept by mailwarm▲287

   AI Agents & Email deliverability experts on your team

   Jul 2026 · mailadept.com · its alternatives →

10. 10
    Context.IO▲226

    API for email inboxes

    2015 · its alternatives →

11. 11
    AnonAddy▲132

    Open-source anonymous email forwarding. Stop spam.

    2019 · its alternatives →

12. 12
    Mailazy▲203

    Cloud email infrastructure for the internet

    2022 · its alternatives →

13. 13
    Keepmail▲146

    Secure and private email forwarding service

    2023 · its alternatives →

14. 14
    Mailercloud Email API Platform▲165

    1,000+ Emails per Second with 99%+ Deliverability

    Mar 2026 · mailercloud.com · its alternatives →

15. 15
    Dmail▲87

    A privacy focused email provider using Blockchain technology

    2019 · its alternatives →

16. 16
    Stampery▲118

    Certify your emails using the blockchain

    2015 · its alternatives →

17. 17FE
    Forward Email – Open-Source Quantum Safe Encrypted Email Service▲35

    2023 · forwardemail.net · its alternatives →

18. 18
    Mailvelope▲61

    End-to-end email encryption for webmail

    2021 · its alternatives →

19. 19
    MailTumble▲79

    URL shorteners for emails

    2021 · its alternatives →

20. 20
    Guardian Digital▲66

    Guardian Digital makes email safe for business

    2021 · its alternatives →

21. 21OA
    Outbound - A single events API for emails, push, sms, and voice▲59

    Empower your product manager. Let them decide what the messages to your users say, when those messages are triggered, as well as how they are sent (sms, email, etc.) while you focus on building product features. They'll be able to use trusted providers like sendgrid, twilio and apple so you don't have to worry about message delivery.

    2013 · outbound.io · its alternatives →

22. 22
    Just Mail▲64

    Secured email platform based on distributed storage network

    2014 · its alternatives →

23. 23SE
    Simple Email API▲15

    2021 · batsign.me · its alternatives →

24. 24MS
    Maildown – super simple email API▲40

    2020 · maildown.dev · its alternatives →

Ranked by how close each launch is in meaning, then by votes. Prices were read from each product’s own site when checked and can change. Refine with your own description →