Count up timer

Is there any way to include a count up timer. Ideally formatted as days/hours/mins/secs.

The background is that I use a sonoff pow with tasmota firmware. Using the total power reading to give the power used over a period of time. I can reset the power recorded but have no way to know how long it has been logging for. I would like to add a timer that can be reset when the logger is reset and show in the front end.

Tasmota reports the ‘Uptime’ of the unit in hours that it is installed on.
Pretty sure this value can be sent from the sonoff via MQTT then templated into a sensor to be displayed in HA

There may be a way to use this as a work around. However resetting the energy reading does not affect the uptime counter.