Our mission at Twilio SendGrid is to provide our customers with the most trusted communication platform. In February 2019, we reached a new milestone: 2 trillion emails processed.

Doing 2 trillion anything takes hard work and is something to be proud of.

We couldn’t be happier to have achieved this milestone.

Any time you’re building and operating a high-transaction software system, the ability to scale that system is the engineering objective, and scale is the primary driver of success in high-throughput systems.

Let’s talk about scale:

  • 2,956: days it took Twilio SendGrid to process our first trillion emails
  • 682: days to process 2 trillion emails

Scaling at this rate isn’t an accident

You plan for it, you build for it, you engineer for it. As recently as 2 years ago, we would be on pins and needles in anticipation of peak sending days like Black Friday and Cyber Monday.

Now, we expect to process well over a billion emails a day. In fact, the last time we processed fewer than 1 billion emails in a day was January 6, 2018.

Let’s talk about daily send rates:

  • The first time we processed 2 billion emails in a day was Cyber Monday 2017. We knew this would be a big day, and we planned for it, and we doubled-down on monitoring the system that day to make sure we’d be successful.
  • Just ahead of GDPR day, May 25, 2018, we processed another 2 billion emails. The difference this time was we didn’t anticipate such a high-volume send day. We had our standard operation plan in place, and came in to work the next day to the pleasant surprise that we had reached our biggest send day to date.
  • Today, we regularly process 2 billion emails a day. During February 2019, we had 3 days where we processed 2 billion emails!

That’s scale!

What does it take to drive email at this scale?

It takes dedication and focus. The Twilio SendGrid Engineering Team has established a development and testing methodology that is aimed at making sure we can take more email traffic, more reliably.

This means we are continuously deploying updates to both our hardware and software infrastructure targeted at improving our email deliverability. When you compare where we were when we processed our first trillion emails to where we are today:

  • Our mean time to deliver emails is less
  • Our deliverability rates are up
  • Our overall system uptime is higher

Not to mention, we do all this while hardening our anti-abuse systems to ensure only the right emails are delivered. This is no small feat.

Where do we go from here?

We see a relatively short runway to 3 trillion emails. We see a roadmap to processing 3 billion emails a day. And we see all this while improving the visibility our customers have to their email deliverability programs through offerings like Email Activity Feed.

More is on the way. And we look forward to working with our new teammates from Twilio on providing even more value to our clients as we continue to scale. Learn more about SendGrid’s email sending infrastructure, authentication, and delivery reputation by heading over to our delivery page. 



Mohammed Attar
Mohammed Attar is the Vice President of Software Development, responsible for Twilio SendGrid’s core Email Infrastructure business, and the Site Executive for Twilio SendGrid’s Orange County office. Mohammed’s career spans roles as a software engineer and a product manager, to leading teams of both types. He joined SendGrid in 2017 from IBM, where he led Product Management for IBM’s Watson Data Platform business. Prior to that, Mohammed held roles at IBM leading both mature and emerging businesses, with teams across multiple sites worldwide. As a development leader at IBM, he was one of the original development managers responsible for the design, development, and delivery of IBM Case Manager, a platform for designing and deploying solutions, leveraging IBM’s industry-leading Content and Process Management offerings, that help people gather the right content, apply analytics for faster, more accurate decisions, and take action to assure better business outcomes.