New Feature: Our Custom Domain feature is now live!

Built for developers

Transactional Emails, Simplified

Keplars Mail Serviceis a developer-first email infrastructure focused on transactional and product emails where you can send emails under 5 clicks. We handle the infrastructure part so teams can ship without worrying about complex setup, deliverability or configuration.

Demo video thumbnail

Demo video

3 min

Role-Based Access Control - Secure team permissions for transactional email API
Secure, Multi-language SDKs
Secure and simple email delivery without app passwords
Secure & Simple
Real-time email analytics and delivery insights dashboard
Smart Analytics Report

What drives us

Keplars is removing friction from email infrastructure for transactional and product emails, giving developers a predictable, boring email-sending foundation, without ongoing setup or debugging - so teams can focus on the product, not email infrastructure.

I've tried several email APIs, but Keplers.email stands out with its simplicity and speed. Perfect for high-volume transactional emails without the hassle. Top-notch service!

Anchit Das

Anchit Das

Co-Founder & CTO @ Stealth AI Startup

Very cool! Thanks for the video that was well made and helpful.

Jonathan Goldsmith

Jonathan Goldsmith

iOS Developer

I really love how you've removed the pain point for developer when configuring a mail service like resend, where I always need to have a domain registered already that I can map to the service.

Sola Maxwell Lana

Sola Maxwell Lana

Full-stack Developer

Have been using other service in the past, I guess a simple REST bases system is much better. I like the product.

Priyanshu Verma

Priyanshu Verma

Co-Founder & Tech @KaizenLabs

Keplers made setting up email for our startup product straightforward and fast. From a backend perspective, the API was clear and developer-friendly, and we had everything running within minutes.

Oluwatobi Makinde

Oluwatobi Makinde

Lead Software Developer

I really like what you’ve built, the user experience is very intuitive. The setup process was smooth and straightforward.

Collins Ndubisi

Collins Ndubisi

Product Designer & Game Developer

I switched from EmailJS to Kepler to focus on code rather than configurations. The instant open and delivery rate tracking gives me total confidence, plus the AI templates save me hours of design work. It is the best choice for developers who value efficiency over complex setups.

Joseph Jonah

Joseph Jonah

Full-Stack Developer

I've tried several email APIs, but Keplers.email stands out with its simplicity and speed. Perfect for high-volume transactional emails without the hassle. Top-notch service!

Anchit Das

Anchit Das

Co-Founder & CTO @ Stealth AI Startup

Very cool! Thanks for the video that was well made and helpful.

Jonathan Goldsmith

Jonathan Goldsmith

iOS Developer

I really love how you've removed the pain point for developer when configuring a mail service like resend, where I always need to have a domain registered already that I can map to the service.

Sola Maxwell Lana

Sola Maxwell Lana

Full-stack Developer

Have been using other service in the past, I guess a simple REST bases system is much better. I like the product.

Priyanshu Verma

Priyanshu Verma

Co-Founder & Tech @KaizenLabs

Keplers made setting up email for our startup product straightforward and fast. From a backend perspective, the API was clear and developer-friendly, and we had everything running within minutes.

Oluwatobi Makinde

Oluwatobi Makinde

Lead Software Developer

I really like what you’ve built, the user experience is very intuitive. The setup process was smooth and straightforward.

Collins Ndubisi

Collins Ndubisi

Product Designer & Game Developer

I switched from EmailJS to Kepler to focus on code rather than configurations. The instant open and delivery rate tracking gives me total confidence, plus the AI templates save me hours of design work. It is the best choice for developers who value efficiency over complex setups.

Joseph Jonah

Joseph Jonah

Full-Stack Developer

I've tried several email APIs, but Keplers.email stands out with its simplicity and speed. Perfect for high-volume transactional emails without the hassle. Top-notch service!

Anchit Das

Anchit Das

Co-Founder & CTO @ Stealth AI Startup

Very cool! Thanks for the video that was well made and helpful.

Jonathan Goldsmith

Jonathan Goldsmith

iOS Developer

I really love how you've removed the pain point for developer when configuring a mail service like resend, where I always need to have a domain registered already that I can map to the service.

Sola Maxwell Lana

Sola Maxwell Lana

Full-stack Developer

Have been using other service in the past, I guess a simple REST bases system is much better. I like the product.

Priyanshu Verma

Priyanshu Verma

Co-Founder & Tech @KaizenLabs

Keplers made setting up email for our startup product straightforward and fast. From a backend perspective, the API was clear and developer-friendly, and we had everything running within minutes.

Oluwatobi Makinde

Oluwatobi Makinde

Lead Software Developer

I really like what you’ve built, the user experience is very intuitive. The setup process was smooth and straightforward.

Collins Ndubisi

Collins Ndubisi

Product Designer & Game Developer

I switched from EmailJS to Kepler to focus on code rather than configurations. The instant open and delivery rate tracking gives me total confidence, plus the AI templates save me hours of design work. It is the best choice for developers who value efficiency over complex setups.

Joseph Jonah

Joseph Jonah

Full-Stack Developer

I've tried several email APIs, but Keplers.email stands out with its simplicity and speed. Perfect for high-volume transactional emails without the hassle. Top-notch service!

Anchit Das

Anchit Das

Co-Founder & CTO @ Stealth AI Startup

Very cool! Thanks for the video that was well made and helpful.

Jonathan Goldsmith

Jonathan Goldsmith

iOS Developer

I really love how you've removed the pain point for developer when configuring a mail service like resend, where I always need to have a domain registered already that I can map to the service.

Sola Maxwell Lana

Sola Maxwell Lana

Full-stack Developer

Have been using other service in the past, I guess a simple REST bases system is much better. I like the product.

Priyanshu Verma

Priyanshu Verma

Co-Founder & Tech @KaizenLabs

Keplers made setting up email for our startup product straightforward and fast. From a backend perspective, the API was clear and developer-friendly, and we had everything running within minutes.

Oluwatobi Makinde

Oluwatobi Makinde

Lead Software Developer

I really like what you’ve built, the user experience is very intuitive. The setup process was smooth and straightforward.

Collins Ndubisi

Collins Ndubisi

Product Designer & Game Developer

I switched from EmailJS to Kepler to focus on code rather than configurations. The instant open and delivery rate tracking gives me total confidence, plus the AI templates save me hours of design work. It is the best choice for developers who value efficiency over complex setups.

Joseph Jonah

Joseph Jonah

Full-Stack Developer