Leon Mika

Anyone making a software tool that converts times between time-zones, please let me enter the time-zone as an offset from UTC.

Something that only accepts time-zone abbreviations or city names are problematic. For one thing, zone abbreviations are location specific. Dealing with technology mainly developed in the US, I’ve got into the habit of writing AEST when I want Australian Eastern Standard Time. But I wouldn’t bat an eyelid if I saw one of my compatriot use EST to mean the same thing. Is your tool smart enough to recognise this, or will it just default to US Eastern Standard Time?

Now granted that’s one that’s got a work around. But let’s say I want to know the time on Low Howe Island. I’d probably use LHST for that, but does that mean “Lord Howe Standard Time” (UTC+10:30) or “Lord Howe Summer Time” (UTC+11:00)? Both of those abbreviate to LHST, and your tool will need to be smart enough to know the particular date and whether or not summer time is in effect. If you think you can handle that edge case, take a look at the list of time-zones abbreviations on Wikipedia to see how you’d be able to handle BST.

What about city names? Yeah, city names might work, but you have to make sure your tool knows of every city out there. I’ve been trying to use Numi to convert from Melbourne time to Apia time. The docs seem to suggest that typing in 13:00 Melbourne time in Apia should work. But as far as I can tell, it doesn’t seem to recognise this as a time-zone conversion expression. It seems to give up and just give me 1:00 pm the answer, possiably because it doesn’t know about Apia¹. I’m wondering if it even knows about Melbourne (I don’t know what each of the colours mean).

And let’s not forget the issue of multiple cities having the same name. Melbourne could refer to Melbourne, Australia or Melbourne, FL, United States. I’d like to see how your tool handles Portland (keep in mind there’s a Portland in Australia as well).

So, please. Make it easy on everyone, including yourself, and just recognise UTC±xx:xx. It would be so much easier and less ambigious if I could just to 13:00 UTC+11:00 to UTC+13:00. Or whatever, pick a syntax that works for you.

And if you do have support for this, please make sure you document it somewhere.