How do you convert weeks to days?
Multiply the number of weeks by 7. If your figure concerns working days, multiply by 5 instead: six weeks is 42 calendar days but 30 working days.
Where these two units are used
The week is the only common time unit with no astronomical basis at all: neither the Sun nor the Moon yields seven days, which come from a religious usage that became universal. The day is 86,400 seconds by convention, but the Earth's rotation drifts: twenty-seven leap seconds have been added since 1972, the last at the end of 2016, and their abolition is settled for 2035. Two weeks have a word of their own in some languages and none in others: English says fortnight, fourteen nights, French une quinzaine, Spanish quincena which mostly names the half-month pay period, while German has only zwei Wochen.
Common durations in weeks and days
| 1 wk | 7 d |
| 2 wk | 14 d |
| 3 wk | 21 d |
| 4 wk | 28 d |
| 6 wk | 42 d |
| 8 wk | 56 d |
| 12 wk (a quarter) | 84 d |
| 26 wk | 182 d |
| 40 wk (pregnancy) | 280 d |
| 52 wk | 364 d |
| 104 wk | 728 d |
Show every value
- 1 wk = 7 d
- 2 wk = 14 d
- 3 wk = 21 d
- 4 wk = 28 d
- 5 wk = 35 d
- 6 wk = 42 d
- 7 wk = 49 d
- 8 wk = 56 d
- 9 wk = 63 d
- 10 wk = 70 d
- 11 wk = 77 d
- 12 wk = 84 d
- 13 wk = 91 d
- 14 wk = 98 d
- 15 wk = 105 d
- 16 wk = 112 d
- 17 wk = 119 d
- 18 wk = 126 d
- 19 wk = 133 d
- 20 wk = 140 d
- 21 wk = 147 d
- 22 wk = 154 d
- 23 wk = 161 d
- 24 wk = 168 d
- 25 wk = 175 d
- 26 wk = 182 d
- 27 wk = 189 d
- 28 wk = 196 d
- 29 wk = 203 d
- 30 wk = 210 d
- 31 wk = 217 d
- 32 wk = 224 d
- 33 wk = 231 d
- 34 wk = 238 d
- 35 wk = 245 d
- 36 wk = 252 d
- 37 wk = 259 d
- 38 wk = 266 d
- 39 wk = 273 d
- 40 wk = 280 d
- 41 wk = 287 d
- 42 wk = 294 d
- 43 wk = 301 d
- 44 wk = 308 d
- 45 wk = 315 d
- 46 wk = 322 d
- 47 wk = 329 d
- 48 wk = 336 d
- 49 wk = 343 d
- 50 wk = 350 d
- 51 wk = 357 d
- 52 wk = 364 d
- 53 wk = 371 d
- 54 wk = 378 d
- 55 wk = 385 d
- 56 wk = 392 d
- 57 wk = 399 d
- 58 wk = 406 d
- 59 wk = 413 d
- 60 wk = 420 d
- 61 wk = 427 d
- 62 wk = 434 d
- 63 wk = 441 d
- 64 wk = 448 d
- 65 wk = 455 d
- 66 wk = 462 d
- 67 wk = 469 d
- 68 wk = 476 d
- 69 wk = 483 d
- 70 wk = 490 d
- 71 wk = 497 d
- 72 wk = 504 d
- 73 wk = 511 d
- 74 wk = 518 d
- 75 wk = 525 d
- 76 wk = 532 d
- 77 wk = 539 d
- 78 wk = 546 d
- 79 wk = 553 d
- 80 wk = 560 d
- 81 wk = 567 d
- 82 wk = 574 d
- 83 wk = 581 d
- 84 wk = 588 d
- 85 wk = 595 d
- 86 wk = 602 d
- 87 wk = 609 d
- 88 wk = 616 d
- 89 wk = 623 d
- 90 wk = 630 d
- 91 wk = 637 d
- 92 wk = 644 d
- 93 wk = 651 d
- 94 wk = 658 d
- 95 wk = 665 d
- 96 wk = 672 d
- 97 wk = 679 d
- 98 wk = 686 d
- 99 wk = 693 d
- 100 wk = 700 d
- 101 wk = 707 d
- 102 wk = 714 d
- 103 wk = 721 d
- 104 wk = 728 d
- 105 wk = 735 d
- 106 wk = 742 d
- 107 wk = 749 d
- 108 wk = 756 d
- 109 wk = 763 d
- 110 wk = 770 d
- 111 wk = 777 d
- 112 wk = 784 d
- 113 wk = 791 d
- 114 wk = 798 d
- 115 wk = 805 d
- 116 wk = 812 d
- 117 wk = 819 d
- 118 wk = 826 d
- 119 wk = 833 d
- 120 wk = 840 d
- 121 wk = 847 d
- 122 wk = 854 d
- 123 wk = 861 d
- 124 wk = 868 d
- 125 wk = 875 d
- 126 wk = 882 d
- 127 wk = 889 d
- 128 wk = 896 d
- 129 wk = 903 d
- 130 wk = 910 d
- 131 wk = 917 d
- 132 wk = 924 d
- 133 wk = 931 d
- 134 wk = 938 d
- 135 wk = 945 d
- 136 wk = 952 d
- 137 wk = 959 d
- 138 wk = 966 d
- 139 wk = 973 d
- 140 wk = 980 d
- 141 wk = 987 d
- 142 wk = 994 d
- 143 wk = 1,001 d
- 144 wk = 1,008 d
- 145 wk = 1,015 d
- 146 wk = 1,022 d
- 147 wk = 1,029 d
- 148 wk = 1,036 d
- 149 wk = 1,043 d
- 150 wk = 1,050 d
- 151 wk = 1,057 d
- 152 wk = 1,064 d
- 153 wk = 1,071 d
- 154 wk = 1,078 d
- 155 wk = 1,085 d
- 156 wk = 1,092 d
- 157 wk = 1,099 d
- 158 wk = 1,106 d
- 159 wk = 1,113 d
- 160 wk = 1,120 d
- 161 wk = 1,127 d
- 162 wk = 1,134 d
- 163 wk = 1,141 d
- 164 wk = 1,148 d
- 165 wk = 1,155 d
- 166 wk = 1,162 d
- 167 wk = 1,169 d
- 168 wk = 1,176 d
- 169 wk = 1,183 d
- 170 wk = 1,190 d
- 171 wk = 1,197 d
- 172 wk = 1,204 d
- 173 wk = 1,211 d
- 174 wk = 1,218 d
- 175 wk = 1,225 d
- 176 wk = 1,232 d
- 177 wk = 1,239 d
- 178 wk = 1,246 d
- 179 wk = 1,253 d
- 180 wk = 1,260 d
- 181 wk = 1,267 d
- 182 wk = 1,274 d
- 183 wk = 1,281 d
- 184 wk = 1,288 d
- 185 wk = 1,295 d
- 186 wk = 1,302 d
- 187 wk = 1,309 d
- 188 wk = 1,316 d
- 189 wk = 1,323 d
- 190 wk = 1,330 d
- 191 wk = 1,337 d
- 192 wk = 1,344 d
- 193 wk = 1,351 d
- 194 wk = 1,358 d
- 195 wk = 1,365 d
- 196 wk = 1,372 d
- 197 wk = 1,379 d
- 198 wk = 1,386 d
- 199 wk = 1,393 d
- 200 wk = 1,400 d
- 205 wk = 1,435 d
- 210 wk = 1,470 d
- 215 wk = 1,505 d
- 220 wk = 1,540 d
- 225 wk = 1,575 d
- 230 wk = 1,610 d
- 235 wk = 1,645 d
- 240 wk = 1,680 d
- 245 wk = 1,715 d
- 250 wk = 1,750 d
- 255 wk = 1,785 d
- 260 wk = 1,820 d
- 265 wk = 1,855 d
- 270 wk = 1,890 d
- 275 wk = 1,925 d
- 280 wk = 1,960 d
- 285 wk = 1,995 d
- 290 wk = 2,030 d
- 295 wk = 2,065 d
- 300 wk = 2,100 d
- 305 wk = 2,135 d
- 310 wk = 2,170 d
- 315 wk = 2,205 d
- 320 wk = 2,240 d
- 325 wk = 2,275 d
- 330 wk = 2,310 d
- 335 wk = 2,345 d
- 340 wk = 2,380 d
- 345 wk = 2,415 d
- 350 wk = 2,450 d
- 355 wk = 2,485 d
- 360 wk = 2,520 d
- 365 wk = 2,555 d
- 370 wk = 2,590 d
- 375 wk = 2,625 d
- 380 wk = 2,660 d
- 385 wk = 2,695 d
- 390 wk = 2,730 d
- 395 wk = 2,765 d
- 400 wk = 2,800 d
- 405 wk = 2,835 d
- 410 wk = 2,870 d
- 415 wk = 2,905 d
- 420 wk = 2,940 d
- 425 wk = 2,975 d
- 430 wk = 3,010 d
- 435 wk = 3,045 d
- 440 wk = 3,080 d
- 445 wk = 3,115 d
- 450 wk = 3,150 d
- 455 wk = 3,185 d
- 460 wk = 3,220 d
- 465 wk = 3,255 d
- 470 wk = 3,290 d
- 475 wk = 3,325 d
- 480 wk = 3,360 d
- 485 wk = 3,395 d
- 490 wk = 3,430 d
- 495 wk = 3,465 d
- 500 wk = 3,500 d
- 510 wk = 3,570 d
- 520 wk = 3,640 d
- 530 wk = 3,710 d
- 540 wk = 3,780 d
- 550 wk = 3,850 d
- 560 wk = 3,920 d
- 570 wk = 3,990 d
- 580 wk = 4,060 d
- 590 wk = 4,130 d
- 600 wk = 4,200 d
- 610 wk = 4,270 d
- 620 wk = 4,340 d
- 630 wk = 4,410 d
- 640 wk = 4,480 d
- 650 wk = 4,550 d
- 660 wk = 4,620 d
- 670 wk = 4,690 d
- 680 wk = 4,760 d
- 690 wk = 4,830 d
- 700 wk = 4,900 d
- 710 wk = 4,970 d
- 720 wk = 5,040 d
- 730 wk = 5,110 d
- 740 wk = 5,180 d
- 750 wk = 5,250 d
- 760 wk = 5,320 d
- 770 wk = 5,390 d
- 780 wk = 5,460 d
- 790 wk = 5,530 d
- 800 wk = 5,600 d
- 810 wk = 5,670 d
- 820 wk = 5,740 d
- 830 wk = 5,810 d
- 840 wk = 5,880 d
- 850 wk = 5,950 d
- 860 wk = 6,020 d
- 870 wk = 6,090 d
- 880 wk = 6,160 d
- 890 wk = 6,230 d
- 900 wk = 6,300 d
- 910 wk = 6,370 d
- 920 wk = 6,440 d
- 930 wk = 6,510 d
- 940 wk = 6,580 d
- 950 wk = 6,650 d
- 960 wk = 6,720 d
- 970 wk = 6,790 d
- 980 wk = 6,860 d
- 990 wk = 6,930 d
- 1,000 wk = 7,000 d
- 1,025 wk = 7,175 d
- 1,050 wk = 7,350 d
- 1,075 wk = 7,525 d
- 1,100 wk = 7,700 d
- 1,125 wk = 7,875 d
- 1,150 wk = 8,050 d
- 1,175 wk = 8,225 d
- 1,200 wk = 8,400 d
- 1,225 wk = 8,575 d
- 1,250 wk = 8,750 d
- 1,275 wk = 8,925 d
- 1,300 wk = 9,100 d
- 1,325 wk = 9,275 d
- 1,350 wk = 9,450 d
- 1,375 wk = 9,625 d
- 1,400 wk = 9,800 d
- 1,425 wk = 9,975 d
- 1,450 wk = 10,150 d
- 1,475 wk = 10,325 d
- 1,500 wk = 10,500 d
- 1,525 wk = 10,675 d
- 1,550 wk = 10,850 d
- 1,575 wk = 11,025 d
- 1,600 wk = 11,200 d
- 1,625 wk = 11,375 d
- 1,650 wk = 11,550 d
- 1,675 wk = 11,725 d
- 1,700 wk = 11,900 d
- 1,725 wk = 12,075 d
- 1,750 wk = 12,250 d
- 1,775 wk = 12,425 d
- 1,800 wk = 12,600 d
- 1,825 wk = 12,775 d
- 1,850 wk = 12,950 d
- 1,875 wk = 13,125 d
- 1,900 wk = 13,300 d
- 1,925 wk = 13,475 d
- 1,950 wk = 13,650 d
- 1,975 wk = 13,825 d
- 2,000 wk = 14,000 d
- 2,050 wk = 14,350 d
- 2,100 wk = 14,700 d
- 2,150 wk = 15,050 d
- 2,200 wk = 15,400 d
- 2,250 wk = 15,750 d
- 2,300 wk = 16,100 d
- 2,350 wk = 16,450 d
- 2,400 wk = 16,800 d
- 2,450 wk = 17,150 d
- 2,500 wk = 17,500 d
- 2,550 wk = 17,850 d
- 2,600 wk = 18,200 d
- 2,650 wk = 18,550 d
- 2,700 wk = 18,900 d
- 2,750 wk = 19,250 d
- 2,800 wk = 19,600 d
- 2,850 wk = 19,950 d
- 2,900 wk = 20,300 d
- 2,950 wk = 20,650 d
- 3,000 wk = 21,000 d
- 3,050 wk = 21,350 d
- 3,100 wk = 21,700 d
- 3,150 wk = 22,050 d
- 3,200 wk = 22,400 d
- 3,250 wk = 22,750 d
- 3,300 wk = 23,100 d
- 3,350 wk = 23,450 d
- 3,400 wk = 23,800 d
- 3,450 wk = 24,150 d
- 3,500 wk = 24,500 d
- 3,550 wk = 24,850 d
- 3,600 wk = 25,200 d
- 3,650 wk = 25,550 d
- 3,700 wk = 25,900 d
- 3,750 wk = 26,250 d
- 3,800 wk = 26,600 d
- 3,850 wk = 26,950 d
- 3,900 wk = 27,300 d
- 3,950 wk = 27,650 d
- 4,000 wk = 28,000 d
- 4,050 wk = 28,350 d
- 4,100 wk = 28,700 d
- 4,150 wk = 29,050 d
- 4,200 wk = 29,400 d
- 4,250 wk = 29,750 d
- 4,300 wk = 30,100 d
- 4,350 wk = 30,450 d
- 4,400 wk = 30,800 d
- 4,450 wk = 31,150 d
- 4,500 wk = 31,500 d
- 4,550 wk = 31,850 d
- 4,600 wk = 32,200 d
- 4,650 wk = 32,550 d
- 4,700 wk = 32,900 d
- 4,750 wk = 33,250 d
- 4,800 wk = 33,600 d
- 4,850 wk = 33,950 d
- 4,900 wk = 34,300 d
- 4,950 wk = 34,650 d
- 5,000 wk = 35,000 d
- 5,100 wk = 35,700 d
- 5,200 wk = 36,400 d
- 5,300 wk = 37,100 d
- 5,400 wk = 37,800 d
- 5,500 wk = 38,500 d
- 5,600 wk = 39,200 d
- 5,700 wk = 39,900 d
- 5,800 wk = 40,600 d
- 5,900 wk = 41,300 d
- 6,000 wk = 42,000 d
- 6,100 wk = 42,700 d
- 6,200 wk = 43,400 d
- 6,300 wk = 44,100 d
- 6,400 wk = 44,800 d
- 6,500 wk = 45,500 d
- 6,600 wk = 46,200 d
- 6,700 wk = 46,900 d
- 6,800 wk = 47,600 d
- 6,900 wk = 48,300 d
- 7,000 wk = 49,000 d
- 7,100 wk = 49,700 d
- 7,200 wk = 50,400 d
- 7,300 wk = 51,100 d
- 7,400 wk = 51,800 d
- 7,500 wk = 52,500 d
- 7,600 wk = 53,200 d
- 7,700 wk = 53,900 d
- 7,800 wk = 54,600 d
- 7,900 wk = 55,300 d
- 8,000 wk = 56,000 d
- 8,100 wk = 56,700 d
- 8,200 wk = 57,400 d
- 8,300 wk = 58,100 d
- 8,400 wk = 58,800 d
- 8,500 wk = 59,500 d
- 8,600 wk = 60,200 d
- 8,700 wk = 60,900 d
- 8,800 wk = 61,600 d
- 8,900 wk = 62,300 d
- 9,000 wk = 63,000 d
- 9,100 wk = 63,700 d
- 9,200 wk = 64,400 d
- 9,300 wk = 65,100 d
- 9,400 wk = 65,800 d
- 9,500 wk = 66,500 d
- 9,600 wk = 67,200 d
- 9,700 wk = 67,900 d
- 9,800 wk = 68,600 d
- 9,900 wk = 69,300 d
- 10,000 wk = 70,000 d
The seven-day week has no astronomical basis: it is a convention inherited from the Babylonian and Hebrew calendars, unrelated to the lunar month or the year. ISO 8601 starts it on Monday and numbers weeks 01 to 52 or 53 depending on the year. Methodology & sources.
Frequently asked questions
Why isn't 52 weeks a year?
Because 52 × 7 = 364, so one day is left over, two in leap years. That remainder is what shifts a given weekday's date by one each year, and what produces ISO years with 53 weeks.
How many months is a 40-week pregnancy?
280 days, roughly nine months and a week. The mismatch comes from an average month being 30.44 days rather than 28: four weeks is not a month, and over nine months the gap adds up to a good ten days.
Does a two-week notice run in working days?
Unless stated otherwise it runs in calendar days: 14 days, weekends included. When a contract means working days it says so explicitly, and two weeks then become 10 working days spread over at least 14 real ones.
Does the week start on Monday or Sunday?
It depends on the region. ISO 8601, followed across Europe, starts it on Monday; the United States, Canada and Japan start it on Sunday. That does not change its length, but it does change the week number of a given date.
Why do some companies count in four-week periods?
To compare like with like. Thirteen periods of 28 days cover 364 days and each holds exactly four weekends, whereas a calendar month holds four or five depending on where the dates fall. Retail and UK payroll use this split, often in a 4-4-5 pattern so that the periods still add up to quarters. The odd day or two is absorbed by a fifth week added every five or six years.