User-Configurable Countdown Timer

This page provides a simple Javascript-based countdown timer. It was created for conference session chairs, so that they can show a remaining-time display to speakers. However, others may find it useful as well.

By default, the timer operates as follows: it counts down from five minutes to zero minutes, updating every ten seconds. When one minute remains, the background turns yellow and the timer is updated every five seconds. At 30 seconds remaining, the background turns red and updates are continuous. Finally, when time runs out, the counter starts blinking.

Nearly all aspects of the counter can be configured by changing entries in the following form. If you want to customize it a lot, you can bookmark the counter page (after hitting "Show the Timer") and your bookmark will remember all the options you chose.

(P.S. Special thanks to Charles Peresso of Malta, who suggested the pause, reset, and "add time" features.)

Timer Options

Count down for minutes and seconds.
Update the counter every seconds.
Use the warning color when seconds are left and update every seconds.
Use the alarm color when seconds are left and update every seconds.
Blink when time is expired:
Continue counting to negative numbers after time is expired:
Provide a button to add time with a default increment of: minutes and seconds.

Appearance Options

Note: all colors can be specified in hexadecimal #RRGGBB format; for example #ff00ff will give a bright purple.

Display the timer in a font.
During the normal countdown, display the timer in on a background.
During the warning period, display the timer in on a background.
During the alarm period, display the timer in on a background.

Sound Options

Beep times at Hertz for milliseconds each when the warning time is reached.
Beep times at Hertz for milliseconds each when the alarm time is reached.
Beep times at Hertz for milliseconds each when time expires.