Cal7 is a proposed leap week calendar that heavily relies on the number seven. A week has, as usual, 7 days, but also a month has 7 weeks and a year has 7 months. The only deviation are odd-numbered months, which have 8 weeks, except for the last one where the eighth week is the leap week. A leap week occurs every 7th year and every 29th year (the rest of the leap rule is yet to be defined). Cal7 can thus be considered a loose solar calendar.
The ISO 8601-like date format is ±YYYY-M-W-D.
| Ordinal | Day | Week | Month |
|---|---|---|---|
| 1 | Monday | Monweek | Monmonth* |
| 2 | Tuesday | Tuesweek | Tuesmonth |
| 3 | Wednesday | Wednesweek | Wednesmonth* |
| 4 | Thursday | Thursweek | Thursmonth |
| 5 | Friday | Friweek | Frimonth* |
| 6 | Saturday | Saturweek | Saturmonth |
| 7 | Sunday | Sunweek | Sunmonth† |
| 8 | (Holiweek) |
| Week | 01 | 02 | 03 | 04 | 05 | 06 | 07 | 08 | 09 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 | 50 | 51 | 52 | 53 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Cal7 | Monmonth | Tuesmonth | Wednesmonth | Thursmonth | Frimonth | Saturmonth | Sunmonth† | ||||||||||||||||||||||||||||||||||||||||||||||
| 4:5:4 | January | February | March | April | May | June | July | August | September | October | November | December† | |||||||||||||||||||||||||||||||||||||||||
| 5:4:4 | January | February | March | April | May | June | July | August | September | October | November | December† | |||||||||||||||||||||||||||||||||||||||||
| 4:4:5 | January | February | March | April | May | June | July | August | September | October | November | December† | |||||||||||||||||||||||||||||||||||||||||
| 13mon | January | February | March | April | May | June | X | July | August | September | October | November | December† | ||||||||||||||||||||||||||||||||||||||||
| Academic | Spring semester | Summer break | Fall semester | ||||||||||||||||||||||||||||||||||||||||||||||||||
| Winter semester | Summer semester | Summer break | Winter semester | ||||||||||||||||||||||||||||||||||||||||||||||||||
| Epiphany/Hilary trimester | Trinity trimester with summer break | Michaelmas trimester | |||||||||||||||||||||||||||||||||||||||||||||||||||
- Fixed (Christian) holidays
- -1-1-1, the first day of Monmonth is New Year (Circumcision/Epiphany of Christ),
- -2-1-1, the first day of Tuesmonth is Shrove Monday,
- -3-1-1, the first day of Wednesmonth is Easter Monday,
- -4-1-1, the first day of Thursmonth is Pentecost Monday,
- -5-1-1, the first day of Frimonth is the day after Transfiguration,
- -6-1-1, the first day of Saturmonth is day after the Feast of the Cross,
- -7-1-1, the first day of Sunmonth is the day after Thanksgiving.