Use data to grow your mailing list

work!”? Ever found that things didn’t quite go as expected? This happened to me recently, but I was in the fortunate position of having data to help solve the problem.

Data graph

Start a mailing list

I recently started a side project; a video screencast series about CSS. I planned to create a series of 26 videos on 26 different topics, each starting with a different letter of the alphabet. You can check them out at

As these would be released weekly over 6 months, I wanted a way to stay in touch with people who watched the videos and tell them about new ones.

Before launching the first video, I created a “holding page” with a bit of info about my plan and a MailChimp email signup form. After a few weeks, almost 400 people had volantarily given me their email address and expressed an interest in what I had to offer.

AtoZ CSS holding page

I get a lot of email so the idea of people actively inviting more was a bit of a surprise to me! Nevertheless, I now had an email list.

Effort vs. Reward

I started making videos and quickly realised that I’d grossly underestimated the amount of work involved. My screencasts are all approximately 5mins in length but each one was taking me hours to produce; anything from 4 to 6 hours in total for each video.

As much as I was honoured that 400 people wanted to watch these videos, I started to want to gather more interest for the amount of work I was putting in. I figured the best way to do that would be to grow the mailing list so I had more people to broadcast to and therefore more people to help by the information I was sharing.

Powerful video hosting

With the idea of wanting to grow my mailing list in mind, but no solution of how to do that, I continued to put togther content and build the website for showcasing it. One of the decisions to make was a video hosting platform. Youtube? Vimeo? Something else…?

A friend of mine recommended checking out video hosting company Wistia as they offer a lot of customisation and features to their embedded player including email capture.

Wistia provides the option of adding email capture before or after a video and this is the message I chose:

Wistia optin capture

I didn’t want to deter users by putting this barrier to entry at the start so decided to have it fly in after the video had finished playing at the end.

This felt like a good plan to me, I didn’t want to annoy anyone and felt that I would get the best engagement with the form at the end. Having watched to the end of a great video and wanting more, it would be a logical next step for someone to subscribe to future episodes.

I’ve heard this logic used with mailing list sign up forms on blog posts too; put it at the end, it’s a great call to action to continue the engagement. This seemed like sound advice.

The data

Pleased with myself for thinking of my users and finding such a useful service, I released the first video and waited for the data and subscribers to roll in.

As well as email capture, Wistia also provide incredible per-video data in the form of an engagement graph.

Wistia engagement graph

This is the engagement graph from my first video. The blue area is the number of viewers over the duration of the video and the red area is parts that were re-watched.

The data shows that only 23% of people who watched the video played all the way to the end. Out of 908 views, this is just 195 people. If we take an arbitrary 5% sign up rate, of 195 people I could optimistically hope to add 10 people to the list per video.

The data I’ve just outlined is 6 weeks worth of views, but I noticed this trend of very few people watching to the end, after just 1 week. In that time, zero people had subscribed via the embedded player.

To date, the first episode has 908 views and 48 people subscribed - 5.29% - which is where I took my arbitrary figure for sign up rate from.


I quickly changed the settings and added the sign up form to the start of each video. I amended the messaging to let people know subscribing was totally optional:

Wistia optin capture

Since doing this, the mailing list has grown steadily.

Around week 3-4, I got a big traffic spike and over 3000 plays of episodes 3 and 4. As a result, the mailing list subscriber numbers increased too.

Here’s the progression of mailing list subscribers against corresponding email campaigns:

Mailchimp subscriber stats


I’m not sure quite how the list size almost doubled between episode 3 and 4 and again between episode 4 and 5 but I’m sure that if I’d left the form at the end of the videos, the subscriber figures would tell a different story.

This was a real learning experience and probably the first time I’ve had enough data to influence my decision. I often go with my gut (which I think is still a valid approach) but having had my initial feelings completely undermined by cold hard data, I’ll definitely be looking to make future decisions based on numbers wherever possible.

If you hate email but still want to keep in touch, follow me on Twitter.

Guy Routledge avatar
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