Time since
Pick any moment in the past and watch a live counter tick the years, months, days, hours, minutes, and seconds since it happened.
0y 0mo 7d 00:00:00
Elapsed since the moment
Total days
6
Total hours
162
Total minutes
9,749
Total seconds
584,946
A static "it has been three months" loses its motivational pull pretty quickly. A counter that ticks up by the second turns a quiet milestone into a visible streak. People bookmark this kind of page for sobriety, exercise streaks, project anniversaries, and time since a major life event. The math is simple, but the psychological effect of watching the numbers move is the point.
When you pick a date and a time without a zone, the calculator interprets the wall-clock you typed inside the zone selector. That matters around daylight saving boundaries. If you quit smoking at 11pm London time on a spring-forward Sunday, the counter behaves correctly because we resolve the input to an exact UTC instant before doing any math. The result is then compared against the current UTC time on your device, so the count keeps ticking accurately wherever you happen to be reading the page.
If you want the gap between two arbitrary dates, use the days between dates calculator. If you want to know the age of a person or pet, the age calculator is the right tool. For working-day arithmetic that subtracts public holidays, see the working days calculator.