Time rounding allows you to round the in and out times to the nearest half hour, quarter hour, 5 minutes, etc. For example if you set time rounding to 15 minutes and a user clocks-in at 7:50 AM their time will be rounded down to 7:45 AM. If they clock out at 5:54 PM their time would be rounded up to 6:00 PM
Rounding rules do not modify the actual times but are instead applied in when you run the reports, so you can safely experiment with different rounding options to see which option works best for your organization.
Time rounding can be enabled from the settings page.