This WebApp calculator can convert the local date time values into the equivalent GPS week and seconds of week format (now with leap seconds included). To use this calculator, simply select your time zone, then type in the local date time in the selected format. Then click the Convert to GPS time button. If the keyed in local date time values do not represent a valid date time string, then the calculator will simply display an error 'Invalid date time' message. Otherwise, the GPS week and seconds of week values will be shown in the GPS Time field.