Introducing Charted

A new way to share data

Mike Sall
Data Lab
Published in
3 min readNov 24, 2014


A year ago, the Product Science team at Medium created the first version of Charted, an internal tool to help us easily share charts. It has since become indispensable to the way we analyze data and communicate our findings with the team. Now we’re opening it up to everyone.

What is Charted?

Charted is a tool that automatically visualizes data. Give it the link to a data file and Charted returns a beautiful, shareable visualization of that data. The charts look like this:

Charted is open-sourced and available for anyone to use at The publicly-hosted works with files that are already publicly accessible to anyone with the link (e.g., Dropbox share links). For protected or sensitive data, you can serve your own instance of Charted on your secure network, which is what we do at Medium.

Why did we build it?

We built Charted for a basic use case:

Turn some data into a simple chart.

It turns out that represents quite a few of our needs. Charted skips the frustrating process of fiddling with options in other programs. It just works. Plus, it adjusts to any screen, automatically updates itself, and provides a permalink that’s easy to share around. With faster and clearer charts, we can spend more time thinking about what they mean.

Internally at Medium, we use Charted everywhere:

  • Checking the results of ad-hoc data queries
  • Sharing our findings from general analyses
  • Building dashboards for each of our teams
  • Displaying metrics on monitors
  • Showing charts during presentations and meetings

Our approach

To focus on that single step — turning some data into a simple chart — we built Charted with a few core principles.

  1. Charted does not store any data.
    It only fetches and visualizes what the link provides. It also refetches the data every 30 minutes, so the chart is always up-to-date.
  2. Charted does not transform or manipulate data.
    It displays only and exactly what it receives. Any necessary calculations or adjustments must already be reflected in the data.
  3. Charted is not a formatting tool.
    It is deliberately sparse in features. Charted focuses on getting from the data to the visualization with the fewest decisions possible.

The resulting tool has only a few (optional) features, so anyone can just plug in the link and go.

How to get started?

Visit and provide the link to a .csv file (such as a Dropbox share link to one). Google Spreadsheets work too. And that’s it!

We’re still working out the kinks, so send your feedback and bug reports. Charted is open-sourced, too, so we welcome collaboration.


The Product Science team at Medium has much more in the works. Want to join us? We’re looking for engineers and product scientists to grow our team.



Mike Sall
Data Lab

Cofounder at @Goldfinch_fi. Previously Head of Product Analytics at @Coinbase, Head of Data Science at @Medium.