2 Clarified date in example.
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Is this for a system where "working days" can change (like this is a piece of software for use by various client businesses), or are working days always M-F?

In either case, you could change the assumption to be that it's counting working days. If that's made known to the users, then you can do the math appropriately and not have to worry about it. So if the business is closed on Sat-Sun, you just count how many weekdays have passed. On Monday, "1 day ago" means Friday.

The catch here is that the user has to do a bit of thinking to figure out what "3 days ago" means if they're seeing it on a Monday. To solve this (assuming today is 7/17/17Monday, July 17, 2017), here's an option:

1 Day Ago (Fri)

3 Days Ago (Wed)

10 Days Ago (6/26)

Is this for a system where "working days" can change (like this is a piece of software for use by various client businesses), or are working days always M-F?

In either case, you could change the assumption to be that it's counting working days. If that's made known to the users, then you can do the math appropriately and not have to worry about it. So if the business is closed on Sat-Sun, you just count how many weekdays have passed. On Monday, "1 day ago" means Friday.

The catch here is that the user has to do a bit of thinking to figure out what "3 days ago" means if they're seeing it on a Monday. To solve this (assuming today is 7/17/17), here's an option:

1 Day Ago (Fri)

3 Days Ago (Wed)

10 Days Ago (6/26)

Is this for a system where "working days" can change (like this is a piece of software for use by various client businesses), or are working days always M-F?

In either case, you could change the assumption to be that it's counting working days. If that's made known to the users, then you can do the math appropriately and not have to worry about it. So if the business is closed on Sat-Sun, you just count how many weekdays have passed. On Monday, "1 day ago" means Friday.

The catch here is that the user has to do a bit of thinking to figure out what "3 days ago" means if they're seeing it on a Monday. To solve this (assuming today is Monday, July 17, 2017), here's an option:

1 Day Ago (Fri)

3 Days Ago (Wed)

10 Days Ago (6/26)

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source | link

Is this for a system where "working days" can change (like this is a piece of software for use by various client businesses), or are working days always M-F?

In either case, you could change the assumption to be that it's counting working days. If that's made known to the users, then you can do the math appropriately and not have to worry about it. So if the business is closed on Sat-Sun, you just count how many weekdays have passed. On Monday, "1 day ago" means Friday.

The catch here is that the user has to do a bit of thinking to figure out what "3 days ago" means if they're seeing it on a Monday. To solve this (assuming today is 7/17/17), here's an option:

1 Day Ago (Fri)

3 Days Ago (Wed)

10 Days Ago (6/26)