What is the fastest email service?
Tags: performance, webdev, beginners, tooling
Published: 2022-12-07 14:28:00

Hi, we are often asked which service to choose. Which is the fastest? Why is email provider X so slow? We will try to answer these questions in this article.

[EmailJS](https://www.emailjs.com/) is an abstract high-level layer for a dozen different email providers that allow users to use a single API to send emails directly from code. It can be called the "intermediary" between the client application and the email provider. This service is already used by thousands of customers, and in terms of this comparison, [EmailJS](https://www.emailjs.com/) is unique.

**Disclaimer**

1. The statistic is carried out only for officially added providers. All custom ones will be in "Others".
2. To connect to providers, either API or SMTP is used. The SMTP protocol is much slower by definition.
3. The statistic includes [personal and transactional services](https://www.emailjs.com/docs/user-guide/connecting-email-services/). Transactional services are built for high asynchronous workloads and are usually faster.
4. The statistic is based on a sample of 30,000 unique users in November 2022.
5. The email provider is an email service and vice versa.

## Top Most Selected
The email provider is most often chosen by customers.

{% embed https://stackblitz.com/edit/emailjs-most-selected-2022?embed=1&hideDevTools=1&hideExplorer=1&hideNavigation=1&view=preview %}

No special discoveries here, with Gmail using over 80%, followed by Outlook with just over 4%. The Mandrill is the least used, which is obvious since the service is very expensive.

## Top Most Called
Shows the amount of total traffic for each email service.

{% embed https://stackblitz.com/edit/emailjs-most-called-2022?embed=1&hideDevTools=1&hideExplorer=1&hideNavigation=1&view=preview %}

The first and second places remained unchanged. However, there are some very noticeable changes in this statistic. The outsider in the previous comparison - Mandrill - has a high traffic.

## Top Request Time
And here is the most expected! This comparison will be divided into two groups: **personal** and **transactional**, to make the comparison fairer. The less time the request takes, the better.

### Personal Services

{% embed https://stackblitz.com/edit/emailjs-fastest-personal-2022?embed=1&hideDevTools=1&hideExplorer=1&hideNavigation=1&view=preview %}

The Gmail service uses an API, which gives it a huge advantage over other services. Zoho has good performance as the SMTP provider. But the average request processing time for Outlook is three times slower than other participants!

### Transactional Services

{% embed https://stackblitz.com/edit/emailjs-fastest-transactional-2022?embed=1&hideDevTools=1&hideExplorer=1&hideNavigation=1&view=preview %}

All comparison participants show low request processing time. Postmark is a bit slower, but Mailjet is the worst on the list.

## Summary

I hope you were as interested in the results as we were. And it was also beneficial for us. What conclusions can we draw?

1. The AOL service has minimal traffic, and customers don't actually use it. It have to be replaced. Any ideas on which one? Maybe ProtonMail?
2. The Outlook provider is popular with [EmailJS](https://www.emailjs.com/) clients but has a slow request processing speed. Microsoft has recently released an API for the email service, and we may look into how to use it.
3. We need to figure out why Mailjet is so slow compared to other providers.

Thanks for reading this article, I'll be happy to read any suggestions for improving future comparisons in the comments.