Calendar.txt is a Text Document That Could Replace Your Calendar App

Gina Trapani, founder of the website you’re reading right now, popularized a plaintext format for to-do lists way back in 2006 (please excuse any weird formatting on that nearly 20-year-old article). Called Todo.txt, it is used by many people to this day, in part thanks to an ecosystem of applications built around the format.

I recently stumbled on Calendar.txt, by author and teacher Tero Karvinen. It’s a text document based on a similar philosophy—a stripped down, just-the-basics take on your overloaded calendar app. It’s a concept worth considering. We’re at least a decade into the “using a separate app for everything” era, and sure, a lot of those apps are pretty great. I’ve spent years recommending software-based tools for everything from managing tasks to making drinks, and I don’t plan to stop anytime soon.

But not everyone needs a bespoke app for everything they do. Productivity is personal, and everyone has different needs. I’ve known several highly technically competent people who still use paper day planners to track their appointments and tasks—a simple notebook is flexible in a way that no app can match.

One line of text per day

I view plaintext tools like Calendar.txt in a similar light. This specific tool is about as simple as it gets: It uses one line of text for every day. You can download a pre-made file with lines for dates that stretches through the year 2033, or you can just make your own.

Every line starts with the date, followed by the week number, followed by a three-letter week name. The idea is that you write your appointments after that, by simply writing the time, followed by the name of the event. Events are simply added, in order, to the line.

So, for example, a line for today, with one appointment/task (me cleaning the house this afternoon) would look like this:

2025-03-06 w10 Thu 14 cleaning the house

There are many shortcomings to this approach. There’s no built-in tool for reminding you of events, for one thing, and there’s no way to invite others to your appointment. But this simple approach might work for you.

And, as todo.txt demonstrated two decades ago, there are benefits to using plaintext files. Plaintext is versatile, can be opened on any device, and your files won’t disappear because some software company decides it wanted to change its priorities. If you’re familiar with the command line, you can use existing tools in all kinds of interesting ways. For example, the calendar.txt documentation shows how you can use grep, a tool for searching text documents, to pull up today’s appointments:

grep 2025-03-06 calendar.txt

You could use the same command to search for events by the day.

Again, this approach won’t seem useful to everyone—especially if you never open the command prompt—but not every tool needs to be for every user. Only you can decide which tools work best for you.