How many seconds are in a week?

604,800, which is 7 x 24 x 60 x 60. Multiples follow from it directly: 2 weeks is 1,209,600 seconds, 4 weeks is 2,419,200 seconds and 52 weeks is 31,449,600 seconds. Type any of those into the From box and the headline comes back as the whole number of weeks, because the factor is exact rather than rounded.

What is the formula for seconds to weeks?

weeks = seconds / 604,800, and seconds = weeks x 604,800 going the other way, which the swap button between the two boxes sets up for you. If you are starting from hours or days instead, change the From menu rather than doing the arithmetic twice: the whole time category is in both menus, and a day converts to 0.142857142857 weeks, one seventh.

Worked example: how many weeks is 1,000,000 seconds?

1.65343915344 weeks. Type 1,000,000 into the From box, with or without the commas, and 1e6 is read the same way. The list underneath restates it as 11.5740740741 days, 277.777777778 hours, 16,666.6666667 minutes, 1,000,000,000 milliseconds and 0.031688087814 years. Every row has its own Copy button, and Copy result above the list copies the headline without the thousands separators.

Why does 1 second read 0.00000165343915344 weeks?

Because one second is 1/604,800 of a week and the page prints it rather than rounding it away. Results carry 12 significant digits, and a magnitude below 0.000001 switches to exponential notation instead of a row of leading zeros, which is why the same 1 second shows as 3.168809e-8 in the years row while the weeks row stays decimal. For a readable figure, pick a unit closer to the size of the span: 1 second is 0.0166666666667 minutes.

How many weeks is a day, an hour or a minute?

A day of 86,400 seconds is 0.142857142857 weeks, an hour of 3,600 seconds is 0.00595238095238 weeks, and a minute of 60 seconds is 0.0000992063492063 weeks. Entering the day, hour or minute directly gives the same answers, since the From menu holds every time unit and the conversion runs through seconds either way.

How many weeks are in a year here?

It depends on the year you mean, and the two do not agree. The Year in this converter is the Julian year of 365.25 days, so 1 year converts to 52.1785714286 weeks and 31,557,600 seconds. A 365-day calendar year is 52.1428571429 weeks, which you can read off the page by entering 365 with Day selected in the From box. Neither is a whole 52, and the converter has no Month unit at all, because a month has no fixed number of seconds to convert with.

Does this account for leap seconds or a clock change?

No, and that is deliberate. Every answer here is a multiplication by a fixed factor, so a week is always exactly 604,800 seconds and a day is always 86,400. A local calendar week that contains a daylight-saving change runs 23 or 25 hours on one of its days, and a leap second adds one second to a UTC day, so a span measured on a calendar can differ from this arithmetic by up to an hour. For spans anchored to real dates, count the dates instead.

What can I type into the box?

Digits, one decimal point, commas as thousands separators, an optional minus sign, and exponent notation such as 1e6. 0 seconds converts to 0 weeks, and -604,800 seconds converts to -1 week, which is what you want when the span is measured backwards. Anything that is not a number leaves a message under the stage naming what was typed and what the box accepts, rather than a silently wrong answer.

Seconds to Weeks Converter

A week in this converter is a fixed 604,800 seconds, seven days of 86,400, so seconds to weeks is one division and the answer never depends on which week of the year you picked. The page opens with Second in the From box and Week in the To box, ahead of whatever pair the converter last remembered, so 604,800 seconds reads 1 week, 1,209,600 reads 2 and 1,000,000 reads 1.65343915344. Under the headline the same span is repeated in every other time unit at once, which is usually the row you actually wanted: 1,000,000 seconds is also 11.5740740741 days, 277.777777778 hours, 16,666.6666667 minutes and 1,000,000,000 milliseconds. Nanoseconds and microseconds are held back behind a Show 2 more switch so the common rows stay readable. The swap button between the boxes reverses the pair into weeks to seconds, where 4 weeks is 2,419,200 seconds.

From

To0.00000165343915344

1 s in every time unit

Millisecondms
1,000
Minutemin
0.0166666666667
Hourh
0.000277777777778
Dayd
0.0000115740740741
Weekwk
0.00000165343915344
Year (Julian)yr
3.168809e-8

Common questions

How many seconds are in a week?: 604,800, which is 7 x 24 x 60 x 60. Multiples follow from it directly: 2 weeks is 1,209,600 seconds, 4 weeks is 2,419,200 seconds and 52 weeks is 31,449,600 seconds. Type any of those into the From box and the headline comes back as the whole number of weeks, because the factor is exact rather than rounded.
What is the formula for seconds to weeks?: weeks = seconds / 604,800, and seconds = weeks x 604,800 going the other way, which the swap button between the two boxes sets up for you. If you are starting from hours or days instead, change the From menu rather than doing the arithmetic twice: the whole time category is in both menus, and a day converts to 0.142857142857 weeks, one seventh.
Worked example: how many weeks is 1,000,000 seconds?: 1.65343915344 weeks. Type 1,000,000 into the From box, with or without the commas, and 1e6 is read the same way. The list underneath restates it as 11.5740740741 days, 277.777777778 hours, 16,666.6666667 minutes, 1,000,000,000 milliseconds and 0.031688087814 years. Every row has its own Copy button, and Copy result above the list copies the headline without the thousands separators.
Why does 1 second read 0.00000165343915344 weeks?: Because one second is 1/604,800 of a week and the page prints it rather than rounding it away. Results carry 12 significant digits, and a magnitude below 0.000001 switches to exponential notation instead of a row of leading zeros, which is why the same 1 second shows as 3.168809e-8 in the years row while the weeks row stays decimal. For a readable figure, pick a unit closer to the size of the span: 1 second is 0.0166666666667 minutes.
How many weeks is a day, an hour or a minute?: A day of 86,400 seconds is 0.142857142857 weeks, an hour of 3,600 seconds is 0.00595238095238 weeks, and a minute of 60 seconds is 0.0000992063492063 weeks. Entering the day, hour or minute directly gives the same answers, since the From menu holds every time unit and the conversion runs through seconds either way.
How many weeks are in a year here?: It depends on the year you mean, and the two do not agree. The Year in this converter is the Julian year of 365.25 days, so 1 year converts to 52.1785714286 weeks and 31,557,600 seconds. A 365-day calendar year is 52.1428571429 weeks, which you can read off the page by entering 365 with Day selected in the From box. Neither is a whole 52, and the converter has no Month unit at all, because a month has no fixed number of seconds to convert with.
Does this account for leap seconds or a clock change?: No, and that is deliberate. Every answer here is a multiplication by a fixed factor, so a week is always exactly 604,800 seconds and a day is always 86,400. A local calendar week that contains a daylight-saving change runs 23 or 25 hours on one of its days, and a leap second adds one second to a UTC day, so a span measured on a calendar can differ from this arithmetic by up to an hour. For spans anchored to real dates, count the dates instead.
What can I type into the box?: Digits, one decimal point, commas as thousands separators, an optional minus sign, and exponent notation such as 1e6. 0 seconds converts to 0 weeks, and -604,800 seconds converts to -1 week, which is what you want when the span is measured backwards. Anything that is not a number leaves a message under the stage naming what was typed and what the box accepts, rather than a silently wrong answer.

Conversion factors are the exact legal definitions where one exists. An inch is exactly 2.54 cm and a pound exactly 0.45359237 kg, so those conversions are exact rather than approximate. Temperature uses offsets rather than factors, and that is shown in the working.