The first proper meeting of the day has a way of arriving faster than the morning's admin allows for. Knowing exactly how much time is left before 10:13 am makes the difference between finishing one more thing and starting something you cannot finish. The countdown here updates on its own, second by second.
Rather than rounding to the nearest minute, the count tracks hours, minutes and seconds the whole way down, in one line. That precision matters most in the last stretch, when the minutes turn into single figures and the difference between leaving now and leaving shortly stops being academic and starts costing you the train.
British speech has a well-worn habit of dropping the middle out of a time: half seven means half an hour after seven, never half an hour before it. Quarter past and quarter to work the same way. Written down, the same moment appears plainly as 10:13 am, or as 10:13 where no ambiguity is allowed.
Common questions
Which clock does it use?
Your own. It reads the local time and time zone from the device you are looking at, so the figure reflects where you actually are rather than a fixed zone written into the page.
Will this alert me when the time arrives?
No. It is a live number rather than an alarm — nothing rings, buzzes or notifies you at zero. If you need to be interrupted at 10:13 am, set an alarm as well and treat this page as the running total.
Is it affected by the clocks changing?
Only in the sense that your device is. When the change between GMT and BST happens at the end of March and October, the device adjusts and the countdown follows it without anything to do here.
What is 10:13 in the 12-hour clock?
That is 10:13 am, or thirteen minutes past ten in the morning if you are saying it aloud. From 13:00 onwards, subtracting twelve gives the pm figure — the same moment written three different ways.