Customer.io Blog

Adam Grant, a professor at Wharton and author of the bestseller Give and Take, is a busy guy. Yet he’s incredibly responsive to email. In fact, he’s famous for his inbox superpowers, described in a New York Times profile as someone who doesn’t say no in the face of hundreds of emails a day and is…

You are cursed. You overestimate how much people understand you. It’s that simple. Psychologist Elizabeth Newton’s 1990 study is a perfect example of how the curse works its counterproductive ways. She split people up into two groups — tappers and listeners. Tappers chose a song from a list of 25…

Do you know how many of the people who start a free trial end up paying you real money? Customer.io has improved from a bad conversion rate to a slightly less bad conversion rate. Here it is reported from our internal dashboard: We currently convert at 3% from sign up to paid. For every 100 si…

“Hey.” That’s the subject line that helped Obama raise 690 million dollars. But how could Obama’s team know it would work? It wasn’t because they had “one weird trick”. They were using a tried and true method: A/B testing. By testing the subject lines, layout, and content of their email marketi…

We often get asked what the best days and times are for sending emails. When it comes down to it, it’s going to depend on your audience. But how do you decide where to begin your tests? Plenty of people have done studies and offer their opinions, but sifting through them takes time. We’ve boiled …

Today we’re going to talk about the dirty stuff — spam reports. The data I’m going to share with you is aggregate stats across Customer.io senders. After reading through this, you should know: Are you better than our average sender in spam reports? Are you worse? If you’re better, send us some hu…

Writing great email copy ain’t worth jack if your emails don’t make it to the inbox. Here’s a quick run down of the critical things you need to improve and track your email deliverability. I learned a lot from reading boring technical articles online and from speaking to Ev Kontsevoy of Mailgun w…

Every time you write an email to your customer, it’s an opportunity for you to get feedback and strengthen that relationship. But as your business starts to scale, how do you handle the volume of reponses? You might be tempted to switch your email address to “noreply”. Please don’t do it. Sending…

Screwing up gave us the opportunity to write an apology email to our customers. Our screw up affected just a fraction of our customers. But each of them received a personal apology. Over the weekend I was reflecting on how we handled the situation and learned that Subway was caught selling “Footl…

What are your rules of thumb for writing emails? Do you have any? Or do you just write stream of consciousness every time? Over time, I’ve come up with about 57 rules of thumb that I follow. But I want share just 5 really important rules of thumb with you today. 1. Write like you speak It took m…