Given that SI already uses the second as a unit of time (as Rubyflame points out supra), here are some conversions:
Standard to metric:
- One minute = 60 s
- One hour = 3.6 ks
- One day = 86.4 ks
- One week = 604.8 ks
- One fortnight = 1.2096 Ms
- One month varies from 2.4192 Ms (28 days) to 2.6784 Ms (31 days). The average month (one-twelfth of a 365 1/4 -day year) is 2.6298 Ms.
- One average year (365 1/4 days) is 31.5576 Ms.
Metric to standard:
- 1 decasecond (das) = 10 seconds
- 1 hectosecond (hs) = 1 minute 40 seconds
- 1 kilosecond (ks) = 16 minutes 40 seconds
- 1 megasecond (Ms) = 11 days 13 hours 46 minutes 40 seconds
- 1 gigasecond (Gs) ≈ 31 years 8 months 7 days 19 hours 46 minutes 40 seconds (based on the average year and the average month)