This page converts days into fortnights using the factor 0.07142857143, and shows the reverse figure alongside it. Both units measure time, which is why one number does the whole job.
Exactly 86,400 seconds by convention (leap seconds excepted). Fourteen days, still the standard pay and rent period in the UK and Australia.
Months and years are not fixed. This page uses the average Gregorian month of 30.44 days and the Julian year of 365.25 days, which is right for durations and wrong for calendars: three months from 31 January is not 91.31 days in any useful sense. Use a date calculator for calendar arithmetic. The tables underneath give both a plain step-by-step lookup and a list of real quantities expressed in fortnights, so you can sanity-check whether your answer is a plausible size.
The formula
days- The amount you are converting, in days
0.0714285714286- The exact number of fortnights in one day
fortnights- The converted result
How it works, step by step
- Enter the value in days.
- It is multiplied by 0.0714285714286, the exact factor between the two units.
- The answer is shown in fortnights, with the reverse conversion beneath it.
- Check the reference table if you want a figure of comparable size.
Worked examples
A pop song: 0.00243 d in fortnights
A pop song comes to about 0.00243 d. Multiplying by the factor: 0.00243 × 0.0714286 = 0.000173571 fn. Dividing the answer back by 0.0714286 returns the figure you started with, which is the quickest way to check you have the factor the right way up.
A mortgage term: 8770 d in fortnights
A mortgage term comes to about 8770 d. Multiplying by the factor: 8770 × 0.0714286 = 626.429 fn. Dividing the answer back by 0.0714286 returns the figure you started with, which is the quickest way to check you have the factor the right way up.
How to read your score
Frequently asked questions
How many fortnights are in one day?
Exactly 0.0714285714286. Every figure on this page is that one number multiplied by your input, so the only rounding is at the display step.
What is the formula to convert days to fortnights?
fortnights = days × 0.0714285714286. Reversed, days = fortnights ÷ 0.0714285714286, which is the same as multiplying by 14.
Which is the bigger unit, the day or the fortnight?
The fortnight. One day is only 0.0714286 of a fortnight, so it takes 14 days to make one fortnight.
What does this quantity actually measure?
Both units measure time. That is why a single factor is enough: there is no temperature offset and no material property involved, unlike conversions that cross between different quantities.
What is a day?
Exactly 86,400 seconds by convention (leap seconds excepted).
What is a fortnight?
Fourteen days, still the standard pay and rent period in the UK and Australia.
Why does my answer differ from another converter?
Almost always because the other tool rounded the factor before multiplying. This page keeps full double precision through the calculation and rounds only for display, and it prints the factor it used so you can see where any difference came from.
Days to fortnights reference tables
| Days | Fortnights |
|---|---|
| 0.5 d | 0.0357143 fn |
| 1 d | 0.0714286 fn |
| 2 d | 0.142857 fn |
| 3 d | 0.214286 fn |
| 5 d | 0.357143 fn |
| 10 d | 0.714286 fn |
| 20 d | 1.42857 fn |
| 25 d | 1.78571 fn |
| 50 d | 3.57143 fn |
| 75 d | 5.35714 fn |
| 100 d | 7.14286 fn |
| 250 d | 17.8571 fn |
| 500 d | 35.7143 fn |
| 1000 d | 71.4286 fn |
| 5000 d | 357.143 fn |
Exact factor: 1 day = 0.0714285714286 fortnights.
| Quantity | d | fn |
|---|---|---|
| A camera flash | 1.157e-08 d | 8.267e-10 fn |
| A heartbeat | 9.919e-06 d | 7.085e-07 fn |
| A pop song | 0.002431 d | 0.0001736 fn |
| A working day | 0.3333 d | 0.02381 fn |
| A pregnancy | 280 d | 20 fn |
| A mortgage term | 8766 d | 626.1 fn |
Published reference values, converted with the same factor this page uses.