Robert Watts and George Maciunas, 10-Hour Flux Clock, 1969.

Why should anyone notice the shape of a watch at the moment of looking at the time?
–Jill Johnston

A computer is a clock with benefits.
–Paul Ford

A calendar is a book that it takes a year to read.
–James Goggin

What time is it on the clock of the world?
–Grace Lee Boggs

In the browser, “now” is a slippery thing. There is the “now” determined by your computer’s time, on the client side. There is the “now” that exists on the webserver, which may be in a different time zone. There is the “now” of CSS and JavaScript, relative to the trigger of an event. And the JavaScript getTime() function returns the number of milliseconds since January 1, 1970.

In life, our experience of time includes phenomena like biological time (chronobiology), ultradian rhythms and circadian rhythms, solar and lunar cycles, celestial time, geological time, decimal time, historical time, psychological time, not to mention subjective time. How do all of these things compound and distort when we experience time on the internet?


Using CSS and JavaScript, create a clock or anything that keeps, marks or utilizes time. Your clock can be as abstract or as literal, as useless or as practical as you like, and it can employ any element or content you like. The important thing is that it comments in a surprising way on the nature of time. Reactivity to the cursor is optional; this could just be an animation that you watch, or it could be interactive.

We are going to approach this project in two parts. The first is to build an animated, ambient website using CSS animations–see Exercise: Ambient website. The second part will be to build a website that uses JavaScript to respond to the current time–see Exercise: Realtime. You could consider the first part a sketch for the second, or treat them as separate prompts.


A long list of clocks online or other time-based artworks.