Convert Week to Second (wk → s)

Converting weeks to seconds is straightforward: multiply by the conversion factor. Follow these three steps to do it by hand or in your head.

1. 1
   Take your value in weeks

   Start with the number of weeks (wk) you want to convert.
2. 2
   Multiply by 604,800

   The conversion factor from wk to s is 604,800. Multiply your value by this number.
3. 3
   Read the result in seconds

   The result is your value in seconds (s).

Multiply the value in weeks by 604,800. For the reverse direction, multiply by 0.000001653.

• ✓1 week = 7 days = 168 hours.
• ✓ISO 8601 week numbering standardises "Week 01 of Year" internationally.
• ✓Some cultures start week on Sunday, others on Monday — check locale.

• ✗Assuming week starts on Sunday in Europe — most of Europe starts Monday.
• ✗Mixing fiscal weeks (e.g. 4-4-5 accounting) with calendar weeks.
• ✗Using "week" in science without specifying Julian or Gregorian basis — rarely matters but can.

What is the Week?

The week equals exactly 7 days and is the standard cycle for work schedules, school terms, weekly publications, and modern social rhythms. Unlike other time units, the week has no astronomical basis — it is a cultural construct whose seven-day length is rooted in ancient Mesopotamian observation of the seven 'planets' (Sun, Moon, Mercury, Venus, Mars, Jupiter, Saturn) and was firmly established in Jewish, Christian, and Islamic religious traditions. The Roman Empire formalized the seven-day week in the 4th century AD, and it has remained globally dominant. The week relates to the day (7 days = 1 week), the month (about 4.345 weeks = 1 month average), and the year (52.14 weeks = 1 year). Work-week conventions vary by country: the standard Monday-Friday week is common in Western nations, Sunday-Thursday in much of the Middle East.

• Weekly schedules, pay cycles, delivery windows
• Pregnancy tracking (measured in weeks)
• Project management sprints

What is the Second?

The second is the base SI unit of time. Since 1967, it has been defined by atomic physics: the duration of 9,192,631,770 periods of the radiation corresponding to the transition between two hyperfine levels of the ground state of the cesium-133 atom. This makes the second extraordinarily reproducible — modern atomic clocks based on optical transitions can keep time to a few parts in 10¹⁸. The second is the foundation of all time measurements: the minute (60 s), the hour (3,600 s), the day (86,400 s). It is also fundamental in physics — speeds (m/s), accelerations (m/s²), frequencies (Hz = 1/s), and Planck's constant all reference the second. International civil time, GPS, and the internet's time synchronization all depend on cesium-based atomic seconds. The second relates to the millisecond (1,000 ms = 1 s), the microsecond, and the nanosecond.

• Everyday timekeeping
• Scientific and engineering measurements
• Sports timing (100 m sprint in ~10 s)