As I plan for calls, meetings, or paper deadlines, I often find that I need to check and compare dates and times in different time zones.
When I had to do this, I would look up entries into websites or use some of the many time zone converters out there, clicking and scrolling to select time zones from large lists of cities. After a while, I got tired of this clicking around and I wished there was a way to just type my query into a search box, hit enter and get the result. You can, for example, google “time London” to figure out the current time in many cities around the world but, e.g. for planning meetings in the future, I needed more than that.
So eventually I sat down and hacked out my own Time Zone Calculator to do just that. Appart from boring queries such as “now”, you can also type “10:00pm from Berlin to Mexico”, or even more crazy things like “tomorrow noon from local to Seoul”. To set up your own local time write in the search box something like “here is Mexico”. All the input is typed into a single search box, making it convenient to save it as a quick search in Firefox or Chrome.
The geek bits: Parsing of the input is done with Perl's Date::Manip which allows the search box to understand many different ‘natural’ ways to input dates and times. Time zone conversion itself is done with the DateTime modules that take into account of all the tricky details such as daylight saving times and the like. To extend the amount of cities available, names of cities are geolocated using the Yahoo! Geolocation API, and then time zones obtained from GeoNames.
Feel free to leave feedback and report problems or errors in the comments section bellow.