A Day In The Life Of An Email

Many companies, regardless of industry, use email as a unique identifier for their apps and services. They use those emails to not only identify you as a customer, but to also send you email updates about their product, welcome emails, password resets, newsletters, promotions, etc. In fact, the average worker receives 300-400 emails per week according to a recent study from Carleton University and an infographic from Atlassian. That’s a lot of email.

Would it surprise you to know that you probably interact with SparkPost in some way every day, at home or at work?

Our customers actually provide you with the latest updates in your social networks (Pinterest, Twitter, LinkedIn), send you coupons and/or alert you to Black Friday or Cyber Monday deals (Tobi, Groupon, Massdrop), and help you make important decisions about your life (Zillow, Zenefits, Paypal, Booking.com). When you look at your inbox, nearly one third is sent on our platform through our customers (3 trillion emails a year and growing).

Take a walk with me through a typical inbox and I’ll show you what I mean.

  • In the morning, Twitter alerts you of what’s trending in the news so you can prepare your day.
  • During the morning commute, Massdrop notifies you to those headphones you’ve been eyeing up just dropped in price. Sweet!
  • Once you arrive at the office, you might receive an email from Zenefits letting you know that open enrollment will start next week.
  • Lunchtime! You head out to try that new Italian deli, Fabrizio’s, thanks to your Groupon daily deal.
  • Later that evening Survey Monkey emails you a questionnaire asking for feedback about your new spin class instructor.
  • On your way home, PayPal emails you a receipt for the online order of flowers to be delivered on your mother’s birthday.
  • After dinner, you receive an email from Booking.com highlighting a trip to Amsterdam you’ve been dying to take.

Whenever you check your email, it’s likely that you are interacting with SparkPost. The who’s who of e-Commerce, retailers, technology companies, publishing companies, and more, trust SparkPost to power their communications. So rest well. We look forward to spending another day with you tomorrow, and the foreseeable future.

~ @tracysestili


Enjoy this Day in the Life of an Email infographic’? Be sure to check out our other infographics.


A few days ago, my colleague Dan looked at how email headers can tell you a lot about where a message came from, the path it took to an inbox, and even whether it actually was sent by who it claims to be from.

But the information contained in headers really is just a start. There’s more that can be measured about the journey of an email—and how well it’s working at the job you’re giving it.

Understanding Product Email Performance

Let’s look at a typical SaaS application email. What’s the basic reason your app is sending an email? It’s because your user has done something, and you need them to take an action to complete the task.

Account signup is a common example:

  1. A user signs up for an account
  2. You need the user to confirm her or his email address to complete the signup

Sounds pretty straightforward, right? Certainly, making sure that process works is essential to keeping your user happy (and not churning). Whether you’re a product manager or on the developer and devops side, making sure emails like this are working is an important part of measuring and managing your product’s overall performance.

Behind the scenes, though, the path that email takes is not as simple as it might seem. Most teams building SaaS products don’t have visibility into what happens once an email like this account confirmation message is sent.

With this article, I’m beginning a series that looks at the life of an account confirmation email, the stages it passes through on its way to the user’s inbox, and how data can be used to understand its performance at each stage.

Generating and Submitting a Product Email

The first step in our message’s journey is the generation and initial submission of the message. Depending on your application, this could happen in one of several ways:

  • Your app generates a fully-formed email and then submits it via Simple Mail Transfer Protocol (SMTP) to an external mail server for transmission.
  • Your app generates the content of a message and uses a simple mail sending function with a local SMTP server on your application host.
  • Or you can use an API provided by a dedicated email delivery service (in shorthand, an email API). This approach is the most scalable, as it allows your app to submit just the relevant data like name and address, while the specialized service handles message generation and delivery.

In any case, the email message is submitted to a Message Transfer Agent (MTA)—i.e., a mail server—that queues the message and takes responsibility for its delivery to the next hop in your message’s journey.

Why Latency Is a Key Metric for Product Emails

Measuring performance at this stage focuses on two metrics, injection count and latency.

The injection count is how many messages you submitted (injected) to the mail server for a given period of time. By itself this count won’t mean much, but it’s a good baseline against which to measure other data.

On the other hand, latency is a critical metric; when you send messages such as signup confirmations, your user’s experience depends on the timely delivery of the message. That’s especially important for something like an account confirmation email—the longer the message is delayed, the lower the likelihood the user will complete the registration and use your product.

If your message assembly and submission system has latency, you may want to review your code to see if it can be made more efficient, in addition, using an email API service can go a long ways towards improving performance, as it offloads the message generation from your own systems.

Typically, an app will only need to gather the recipient name, email, and other small amounts of personalization data and submit it to the API. The service then takes care of assembling and personalizing the messages and queuing them for delivery.

How to Measure Email Delivery Latency

Another component of email latency is how long it takes for your mail server (MTA) to deliver the message to its next stop, typically the inbound mail server operated by your user’s ISP. (Gmail or iCloud are typical examples.)

At this stage, some factors are out of your control, but latency here is a good indication of the overall quality of your email infrastructure. It’s a function of your infrastructure’s technical architecture and performance as well as its ability to manage delivery to ISPs. Both of these areas are where a high-performing email delivery service typically exhibits a major advantage over in-house email systems.

If your systems are slow at processing messages, or at managing queues, or are simply overworked, you’ll see latency of a minute or more. Efficient systems should be operating with a latency of less than ten seconds on average. There will always be some variation, as is common with all complex systems, but it’s the long-term trends that should concern you.

When you see latency numbers that are consistently high, you need to look at the underlying infrastructure: are there too many systems in the middle of your sending? Even your message generation process could be at fault: pickup directory systems can be relatively straightforward to build, but they are often based on scheduled pickups, which can introduce a long wait for a message submitted just after the last pass of the reader.

Latency after the first attempt is an indication of your reputation with the ISPs. Often an ISP will reject your message on the first attempt as a form of greylisting, refusing the first attempt at delivery to see if your MTA makes a second attempt (many spam bots will try once and move on). This causes the message to be queued and deferred temporarily for a subsequent attempt. The longer it takes to deliver a multi-attempt message, the more likely your sending reputation needs improvement.

How to Measure Latency by Hand

If you don’t have analytics in a dashboard for latency data, you’ll have to gather it yourself. Setting up scheduled jobs that send messages through your infrastructure to dedicated mailboxes that you maintain on the major ISPs, then retrieve the messages and check the timestamps of the first Received header and the Date header to determine the latency (note in the example below the time zones must be accounted for when calculating latency).

Email latency is a very important part of product email performance, but it’s just the start. Stay tuned for our next installment: understanding message delivery and what happens when a product email is delayed or never arrives.


now sending 15 billion emails

Let me begin by saying that this is the sort of blog post a CEO loves to write.

When SparkPost launched 18 months ago, we knew developers were looking for a better way to send email from their web and mobile apps. We knew enterprise senders needed more reliable delivery for email that was critical to their business. And we had a clear vision for how to meet those needs, with a next-generation cloud architecture backed by a team that understood email better than just about anyone else on the planet.

But even so, we knew that there was one thing that was going to be absolutely essential to our hoped-for success: you. We were optimistic, of course, that the market would recognize the value of what we were building. But the growth we’ve experienced in the last year and a half has exceeded our expectations.

We’re now delivering more than 15 billion messages each month, and that figure is growing by more than 1 billion per month. To put it simply, SparkPost is the fastest-growing email delivery service on the market.

That growth is because of you. We’ve just been thrilled that so many developers and enterprise customers alike understand the benefit of what SparkPost has brought to the table—and to see the sorts of innovative things our customers are doing with email today. SparkPost’s 15,000+ active customers range from small startups to fast-growing major technology companies including Pinterest, Zillow, CareerBuilder, LinkedIn, and Intercom.

Beyond the numbers, I’d like to highlight three areas that reflect SparkPost’s leadership and growth:

  • SparkPost is now the preferred choice of developers for API-driven email delivery. This was evidenced by the recent migration of many Mandrill users to SparkPost after MailChimp announced it would no longer be available as a standalone service. The resulting surge of users to SparkPost was captured in a recent Notablist report analyzing the Mandrill market disruption; this analysis found that over 21 percent selected SparkPost—5 percent ahead of the closest competitor—prompting Notablist to state that “SparkPost Won the Battle for New Users.”
  • SparkPost has earned our reputation as the most reliable and flexible email delivery service provider. Unlike other email delivery providers who continue to expend resources and focus on building and maintaining  their own data centers, SparkPost is the only full-featured cloud email delivery service built 100 percent for the modern cloud.  SparkPost’s leverage of Amazon Web Services, the industry’s preeminent Infrastructure-as-a-Service (IaaS) platform, allows customers and partners alike to experience the benefits of a secure, scalable, and elastic cloud infrastructure—like guaranteed burst rates—while allowing SparkPost to remain focused on developing and expanding its core service offerings and technical innovations.
  • SparkPost is focused on email delivery—and we love our MarTech partners. We’ve developed more than 30 strategic partnerships with innovative marketing technology (MarTech) companies. These marketing application providers give SparkPost customers the combined benefit of leading-edge MarTech functionality with the high-performing email delivery service that is SparkPost’s clear focus.

2016 has proven to be a year of remarkable growth for SparkPost. And I fully expect the next 18 months will be even better.

So, a heart-felt thank you. I can’t wait to see what we build and grow together.

—Phillip Merrick

Email Marketing Rookie Kid Missing Steering Wheel

Avoid these mistakes and being labeled an Email Marketing Rookie

Everyone loves a good list. Letterman might’ve been the greatest list maker/reader/practitioner – inspiring and empowering an entire generation of copy writers that regale us with their amazing listacles all around the web! We thought we’d throw our hat into the fray and put together a list of common mistakes, with a heavy dose of snark, on how to avoid being labeled an email marketing rookie.

  1. Everyone wants to hear from us. No really, everyone! No, no, everyone doesn’t want to hear from you. Some only wanted to hear from you once to buy a specific item and then unsubscribed or marked your email as spam. Assuming everyone wants to hear from you is tantamount to ignoring your customers.
  2. Cadence, shmadence, I wanna be in their inbox every single day! How often you send email is important, the time that you send it can be directly tied to your business, e.g. you run a restaurant that wants to advertise lunch specials, sending it at 1145 might’ve missed the mark.
  3. Responsive design? What’s that? It’s what makes emails look good on mobile phones. Responsive email templates are not only the rage, but in our hyper mobilized world they’re an absolute necessity.
  4. Bounces? We didn’t bounce, we just didn’t make it all the way in so we’re gonna keep trying that email until it delivers! That’s spot on–NOT! So if you do that, you may look like a spammer to an ISP. Spammers don’t respect hard bounces, they send lots of emails that will hard bounce, and generally don’t do anything about soft bounces. Bounce policy is what sets you apart from the bad guys and helps you build a positive sending reputation.
  5. A friend told me that he knows a guy that knows a guy that has a really big opt-in database for sale! We could triple or quadruple our open rates! Don’t ever do this. Just don’t. It won’t end well. I assure you; and so will a lot of other experts in the field. This is not the marketing strategy you’re looking for.
  6. Use as many IPs as possible. If one gets blocked, just route the mail on another one! Again, this is a tactic commonly used by spammers. If you do this you will only decrease the likelihood your email will arrive to the inbox. Setup an IP for commercial email, and one for transactional and build positive sending reputations on both. That’s the only route to success.
  7. Unsubscribes are for losers. I can’t. No Seriously. Where do I begin? Unsubscribes are not only a good practice to avoid making your customers angry, but it’s required by the CAN-SPAM act of 2003. You must have a working electronic unsubscribe. That’s all there is to it.
  8. We’re going to make email great again by sending as much of it as possible! Then you might as well shutter your business now and save us all a lot of grief and clicks of the spam button. The right amount of email will change from business to business, but what’s universal is that everyone has a threshold where enough is enough. Experiment with different amounts of email for different users. This means having data to gauge how and when they consume your email.
  9. Targeting? We don’t target, we canvas! Ever heard the phrase the right email for the right person, at the right time and optimized for the right platform? Well now you have. Targeting an offer to a person most likely to be receptive to it requires past purchase history, preference centers, opens, clicks, unsubscribe data, all of the things that help you be smart about your digital communications.
  10. Segmentation? We use a segment of one: everyone gets every email. No no no no. This isn’t how it works. A segment of one means you know so much about your customer that everyone is unique and you personalize the heck out of every communication making it a unique experience. Yeah, it’s not easy, you need real time data, flexible templates with personalization capabilities in your platform and an appreciation for how different segments should be marketed to in different manners and with uniquely different content at times.
  11. Blacklist? Wasn’t that something that happened in Hollywood in the 50s during McCarthyism? Yes there were blacklists in Hollywood, and it’s also a show starring James Spader. However, blacklists are very real and very damaging should your IP or sending domain land on one. Having integrated tools like 250OK in your email platform reduces the likelihood of being on a blacklist and not knowing, and expedites remediation (along with a crack deliverability team) should you land on one.
  12. SPF, DKIM, DMARC, ARC… stop my head’s hurting from all these acronyms. Acronyms got you down? I know you how you feel. However this is important so listen up. SPF, DKIM, DMARC, ARC these are all part of a category of technologies called email authentication and they are really important because they help you protect your brand, and your customers, from phishing and spammers. You don’t want some criminal halfway across the world spoofing your domain and pummeling inboxes with email designed to defraud people do you? You know what happens then? You get laid off, your business fails and the dark side wins. Talk to your tech team, or our tech team and we’ll help you navigate the authentication waters.
  13. We should try and win back every customer that unsubscribes, you never know, they may change their mind! Whooooa, hold your horses there! I agree, you should try to win them back, but re-subscribing unsubscribers is a major no-no, you can land in hot water with numerous folks. However, getting inactive subscribers to become active is an absolute strategy and you should do it like so: slowly and with extreme caution. I’ve heard from ISP postmasters that re-engagement campaigns generate high complaints and that’s bad news for a sending IP or brand. Send these emails slowly in very small batches around the clock. Make it an ongoing best effort basis vs. a giant airdrop all at once.
  14. Subject lines need to be big bold and say anything to get them to click. No, no they don’t. No really, if you don’t believe me read the FTC’s guidelines. Truth in advertising. Be edgy, be bold, be creative, be all that, just be honest. If not, refer to rule #12.
  15. Put as many offers as you can into the receipt or shipping confirmation. It’s a guaranteed chance to get in front of them for more sales! I’m gonna say fuhgeddaboudit! Transactional email closes the loop on a transaction, generally initiated by a customer. There is an unwritten rule that says 80% of the content in a transactional email should be just that, transactional, 20% marketing. If you pack in too much marketing you change the fundamental content and nature of the communication. Transactional email should be sent on its own IP to create a ‘separation between church and state’ from commercial email for just this reason.
  16. Hey why don’t we make the font for our unsubscribe link white, like the background?! Once again I get to say don’t you dare! And why do I say this? I refer you back to the FTC’s guidelines. Let this be your guiding principle: clean and conspicuous. And if you need another reason chew on this: if someone unsubs they can always re-sub at some later point. If they mark your message as spam because they can’t find the unsub link, or you didn’t include it, then your entire reputation suffers, its harder to deliver email, your revenues decline, you get fired and the dark side wins. Which do you prefer?
  17. Someone said millennials like snark, can we just make our postal address 1600 Pennsylvania ave? Or maybe 666 Elm St.? Who reads that stuff anyway?! And you wouldn’t believe what will happen if you do this. Yeah, once more, FTC, CAN-SPAM, valid, physical mailing address is required. And if you need another reason: you’re not a spammer, so don’t act like one!

There you have it! A comprehensive list of email marketing rookie mistakes, and how to avoid them. Anything we missed or overlooked? Leave us a comment!

Zillions Guide Blog Footer

Developer Week Recap

best use of api sparky award

Last week was a whirlwind of shaking hands, making connections, and building awesome things! From early Saturday morning until late Wednesday night, we talked to Developer Week attendees. The focus? What makes SparkPost different, how to use our awesome API, and why we’re the top choice for an email delivery platform. Here are a few of the highlights:

The Hackathon

hackathon developer week

The energy at the Galvanize co-working space was electric. With so many teams working on such amazing apps, we felt privileged that so many chose to work with us! We had teams building everything. From an app to manage food truck orders (for both vendors and customers), to a service that uses IBM’s Watson to analyze the tone of your emails before you hit send. Everyone could use a feature like that some days, am I right? Another team used our data and analytics UI to store webhooks and campaign data in order to easily re-send an email. The most innovative use of SparkPost however, was DwellWell.


Anyone who has spent a fair amount of time in San Francisco (or anyone who pays attention to the housing market), knows that one of the biggest problems here is a lack of affordable housing. There are several hoops to jump through to gain access to affordable housing, one of them being a mountain of paperwork. The DwellWell team, led by Marlon Frausto, built an app that enables applicants to complete their paperwork online, rather than making a trek downtown to deal with lines in person. The team did their research ahead of time, to gather all requirements for the affordable housing application process. Using SparkPost’s API, they built out a double-blind email system that allows people to inquire about a specific housing options. In addition to solving other problems, this gives applicants the anonymity they’re often wanting, but unable to have throughout the older process.

As they continue to build out the application and work with the city housing authority, we’ll be following their story and supporting their use of SparkPost.

dwell well hackathon

Dev Week Expo

Tuesday and Wednesday were the Developer Week Conference & Expo, inside the beautiful Pier 27 Cruise Ship Terminal. While we didn’t spend any time on a cruise ship, we did get to interact with several hundred attendees from all over the globe. We got great feedback on our API and had more interesting conversations about the various ways SparkPost can be used. Best of all, we got to see people get excited about building something awesome!

Build something awesome

If we didn’t get a chance to chat at Developer Week, say hi on Twitter! Tell us what you’re working on! You’ll also find us at BrickHack and FluentConf next month. Be sure to stop by and say hi!

EmailAgeAPIsSMTP, the standard that defines email, is 30+ years old. Since the first email was sent the technologies used to implement, personalize, optimize, test, target, segment and deliver highly relevant messages from companies to consumers have dramatically evolved in terms of sophistication and potency.

What may have started as a single isolated email platform within a company’s technology stack has had to keep pace with the market’s evolution and the increased importance placed the digital marketer’s ability to drive revenue. As such, email systems and infrastructure have had to evolve to be leaner, more flexible and infinitely scalable, and to handle traffic from multiple stakeholders within an organization. In order to minimize the overhead of complex systems, multiple ESPs and external agencies, programmatic sending, targeting, template generation and deployment have become critical to ensuring that email deployment systems are as internally relevant as the content they’re sending.

The emphasis, naturally, is on cloud-based technologies—the migration of infrastructure, platforms and software to the cloud have been made possible through the standardization of APIs to link disparate systems. More importantly, business processes are being modeled through flexible REST frameworks that allow the customization of cloud-born technologies and infrastructures to meet a company’s unique and proprietary needs.

However golden the future may appear, there exists a reality that has to be understood: not all APIs are built alike. Not only do APIs differ, but platforms and infrastructure have vast differences in how they can be modeled, adapted and used to service the numerous outbound email needs of any company. Our new white paper, Email in the Age of APIs, was written to help technology buyers, and marketers, understand the nuances of API-driven email, how the technology can be transformative to an organization, the benefits and the pitfalls associated with the build-out of monolithic stacks. To learn more download Email in the Age of APIs.

Shared vs Dedicated Email Environments: A Practical Guide



maximum_overdrivePhilosophically speaking, and here I’m not sure which ‘geek’ bucket this fits in, but I’m really excited about SMTPUTF8. Before you click back to Facebook or Buzzfeed, allow me a chance to explain: we’re all cruising along this digital super highway we call the Internet. (more…)


Over the past few weeks we’ve seen a number of articles all of which show that the tech industry is having a resurgence of interest in email — which many folks had written off with the advent of social media.

Here are links to a few of them:

These articles point out in many ways how all that is old is new again.  Mobile and social networks have actually increased email readership and volumes, and email is a critical part of engagement for both mobile and social.

Since I started at Message Systems I’ve had friends and neighbors ask me about what we do here.  When I say we move 20% of the world’s email, many are impressed, but some have looked at me quizzically and said something like: “But I thought email was going away”. I then ask them what the first thing they do is when they wake up in the morning. Most answer: “Pick up my smartphone”. And then I ask, “And what do you check first?”. 98% of the time the answer is: “My email”. Right. In fact email is still the top application used on mobile phones, according to surveys I have seen, including one conducted by Facebook and IDC last year that showed that email is used by 78% of all smartphone users.

Despite famous predictions about email being doomed in past years, it is indisputable that email is still the Internet’s number one communications channel.  Message Systems is already the dominant provider of email for high volume senders like Facebook, Twitter, LinkedIn and Groupon. Through superior innovation, Message Systems intends to make email an even stronger channel for connecting companies with their customers or member community.

This is a tremendously exciting time for email and Message Systems, and I can’t wait to see how the next few years play out.

Viva email!


Learn more about the future of email marketing. CEO of the Relevancy Group, David Daniels, provides exclusive insight into the current State of Email Marketing in this webinar.


This past weekend marked the unofficial end of summer here in the US. Yesterday was labor day, and for most people that meant it was a three-day weekend. That typically translates to outdoor activities like grilling hotdogs and burgers, fishing, and spending good times with friends and family. This also means you can no longer wear white in some circles, and the dreaded back-to-school feeling for the lucky ones who start their school year later than others.

For us here in the San Francisco bay area, the big “event” was the 5-day closure of the San Francisco-Oakland bay bridge. This long overdue 10-year, 6.4 billion dollar project was to replace the old bay bridge that was damaged in the 1989 Loma Prieta earthquake. The replacement span is designed to withstand the strongest earthquake estimated by seismologists to occur at the site over a 1,500-year period.

The old bridge was closed over the long weekend to allow crews to finish connecting the new bridge and getting it online. Scheduled to open at 5 am Tuesday morning, pictures of the first people crossing the new span already started showing up on social media around 10 pm Monday night. And it’s a pretty good-looking bridge.




Speaking of bridges, Message Systems today also released a fun new video showing how we can help you bridge the gap between you and your customers more easily, across multiple channels, more effectively. (See what I did there?)

You can check it out below. Enjoy!