Last orders and the walk home are the traditional end of an evening out, and both hinge on a specific time rather than a general sense of lateness. If 11:48 pm is that point, this page counts down to it exactly, right down to the second, for as long as it stays open on a screen.
Because the count reads straight from your device's clock, its accuracy rests on that clock being right, time zone included. Phones and computers normally handle this themselves, so in practice the figure here lines up with whatever time the device is already showing elsewhere on screen.
Writing a time as 11:48 pm keeps the am or pm attached, which reads naturally in a sentence but is easy to skim past in a long list of similar entries. Writing it as 23:48 is less conversational and considerably harder to misread, which is why schedules and rotas lean that way.
Common questions
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 23:48 in the 12-hour clock?
That is 11:48 pm, or twelve minutes to twelve at night if you are saying it aloud. From 13:00 onwards, subtracting twelve gives the pm figure — the same moment written three different ways.
Does the number update by itself?
Yes. It recalculates every second from your device's clock, so there is nothing to refresh or restart. Whatever is on screen is the current gap to the target time, not a figure worked out when the page first loaded.
What happens if 11:48 pm has already gone for today?
The count simply carries on towards the next occurrence, which is tomorrow. That rollover happens on its own — the page does not need reloading and there is nothing to reset by hand.