Sendwithus aims to bring optimization and A/B testing to marketers and anyone else sending out targeted promotional emails.
The company, which is part of the current class of Y Combinator-incubated startups, was founded by Matt Harris and Brad Van Vugt. Harris told me that Sendwithus emerged from the pair’s work as developers, when they found themselves repeatedly having to change a bunch of email templates and wanting to test different variants but finding that there was no real technology in place to do so. (Larger companies will usually build their own systems for this, he said.)
So Sendwithus created a website where customers can select from pre-made email templates or upload their own, log in to their preferred email provider, and then set up A/B tests and drip campaigns. Customers also have access to analytics showing how variants and campaigns are performing.
Harris said Sendwithus is focused on “transactional emails” (i.e., the emails that are sent to specific users at specific times, usually to accomplish a specific task) as opposed to newsletters or other broad campaigns. Just managing all the different templates and automatically sending the right one out at the right time is important to the company’s customers, he added.
Plus, those templates are dynamic, and not just in the sense of filling in your name at the right spot. For example, Harris said that whenever one company using Sendwithus sends a lost password email, it checks to see whether the person receiving the email is a free or paid customer. If they’re free, the company add a short “upgrade to our paid plan” message at the end of the email.

As I mentioned, Sendwithus integrates with existing email delivery services, including SendGrid, Mandrill, Mailgun, and Amazon Simple Email Service. I asked Harris if he might find himself competing with those services down the line, and he didn’t sound too worried, because he said, “Email deliverability, one of the reasons it’s taken so long is that it’s a really hard problem that they’re solving, and we’re solving a hard problem, too.”
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Founded 11 months ago, Sendwithus already processes more than 1 million emails a day, he added, and its customers include 8tracks, uSell, SuperRewards and App.net. Pricing starts at $19 a month. Update: There’s also a free version for emailing up to 100 customers.
