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 ±CCYY-M-W-D. If not specified otherwise, Cal7 agrees with this international standard, e.g. that Monday is the first day of the week.
| 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) |
In the table, an asterisk * denotes months that always include Holiweek and a dagger † shows the month that is 8 weeks long only in leap years.
Comparison[]
The following table compares Cal7 with similar proposals, assuming weeks start on Monday in all cases. The academic terms listed are synchronized with Cal7 months; they could be aligned with other months instead.
| 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 13mon | Janon | Febron | Marchon | Apron | Mayon | Junion | Extron | Julon | Augon | Septon | Octon | Novon | Decon † | ||||||||||||||||||||||||||||||||||||||||
| 5:4:4 | Janaire | Febraire | Marchose | Aprilose | Mayose | Junal | Julial | Augial | Septidor | Octidor | Novidor | Decaire † | |||||||||||||||||||||||||||||||||||||||||
| 4:5:4 | Janose | Febrose | Aprial | Mayal | Julidor | Augidor | Octaire | Novaire | |||||||||||||||||||||||||||||||||||||||||||||
| 4:4:5 | Febral | Marchal | Maydor | Junidor | Augaire | Septaire | Novose | Decose † | |||||||||||||||||||||||||||||||||||||||||||||
| Quarter | quart 1 | quart 2 | quart 3 | quart 4 † | |||||||||||||||||||||||||||||||||||||||||||||||||
| 7:6 | Bol | Sar | Tan | Lit | Nas | Mon | Sam | Yul † | |||||||||||||||||||||||||||||||||||||||||||||
| 4:5* | Janose | Febrose | Marchose | Aprilose | Mayose | Junal | Julidor | Augidor | Septidor | Octidor | Novidor | Decaire † | |||||||||||||||||||||||||||||||||||||||||
| 9:9:8 | sester 1 | sester 2 | sester 3 | sester 4 | sester 5 | sester 6 † | |||||||||||||||||||||||||||||||||||||||||||||||
| 5:5:6:5 | Primoth | Secoth | Tertoth | Quaroth | Quintoth | Sixtoth | Septoth | Octoth | Novoth | Decoth † | |||||||||||||||||||||||||||||||||||||||||||
| 10:11 | quinter 1 | quinter 2 | quinter 3 | quinter 4 | quinter 5 † | ||||||||||||||||||||||||||||||||||||||||||||||||
| 8:7 | Monmonth | Tuesmonth | Wednesmonth | Thursmonth | Frimonth | Saturmonth | Sunmonth † | ||||||||||||||||||||||||||||||||||||||||||||||
| Terms | Spring semester | Summer break | Fall semester | ||||||||||||||||||||||||||||||||||||||||||||||||||
| Winter semester | Spring break | Summer semester | Fall break | Winter semester | |||||||||||||||||||||||||||||||||||||||||||||||||
| Epiphany/Hilary trimester | Trinity trimester | Summer break | Michaelmas trimester | ||||||||||||||||||||||||||||||||||||||||||||||||||
Holidays[]
The Christian holidays are fixed as follows: Carnival, Easter and Pentecost are at month boundaries, 7 weeks apart. Christmas Eve is one week before New Year’s Eve unless there’s a leap week and Lady Day is 40 weeks before Christmas (not 9 months).
Note that Halloween is on -6-6-6, a Saturday. Most holidays are conveniently placed onto Sundays, unless they are already associated with a fixed day of the week.
| Holiday | Date | Notes | |
|---|---|---|---|
| New Year | -1-1-1 | the first day of Monmonth | |
| Circumcision of Christ | -1-1-1 | the first day of Monmonth | |
| Epiphany | -1-1-7 | was 6 Jan or Sunday close by, also Theophany | |
| Candlemas | -1-4-7 | was 2 Feb or Sunday close to it, Presentation of Jesus at the Temple | |
| Valentine’s Day | -1-6-7 | was 14 Feb | |
| Shrove Monday | -2-1-1 | the first day of Tuesmonth, 7 weeks before Easter | Carnival |
| Mardi Gras | -2-1-2 | ||
| Ash Wednesday | -2-1-3 | ||
| Women’s Day | -2-2-7 | was 8 Mar | |
| Lady Day | -2-3-7 | was 25 Mar, Feast of the Annunciation of the Blessed Virgin | |
| Maundy Thursday | -2-7-4 | Easter | |
| Good Friday | -2-7-5 | ||
| Easter Sunday | -2-7-7 | the last day of Tuesmonth (a week later than proposed for Sym454) | |
| Easter Monday | -3-1-1 | the first day of Wednesmonth | |
| Labor Day | -3-3-3 | -3-3-1? -3-7-5?, Workers’ Day was 1 May (or 1st Mon in Sep in NA) | |
| Mother’s Day | -3-3-7 | was 2nd Sun in May etc.pp. | |
| Father’s Day | -3-4-7 | was 3rd Sun in Jun etc.pp. | |
| Ascension | -3-7-4 | 40 days after Easter | Pentecost |
| Pentecost Sunday | -3-8-7 | the last day of Wednesmonth, 7 weeks after Easter | |
| Pentecost Monday | -4-1-1 | the first day of Thursmonth, Our Lady of Holy Church | |
| Trinity Sunday | -4-1-7 | ||
| Corpus Christi | -4-2-4 | 60 days after Easter | |
| Midsummer | -4-2-7 | was ca. 21 Jun | |
| Feast of the Transfiguration | -4-7-7 | the last day of Thursmonth, was 6 Aug | |
| Feast of the Cross | -5-8-7 | the last day of Frimonth, was 14 Sep | |
| Michaelmas | -6-1-7 | was 29 Sep, Feast of the Archangels | |
| Halloween | -6-6-6 | a Saturday, was 31 Oct, Samhain | All Hallows |
| All Hallows | -6-6-7 | was 1 Nov | |
| All Saints | -6-7-7 | the last day of Saturmonth | |
| Thanksgiving | -7-1-7 | Harvest feast, was 4th Thu in Nov, 2nd Mon in Oct, 1st Sun in Oct etc.pp. | |
| 1st Advent Sunday | -7-2-7 | Advent | |
| St. Nicklas | -7-3-6 | was 6 Dec | |
| 2nd Advent Sunday | -7-3-7 | ||
| 3rd Advent Sunday | -7-4-7 | ||
| 4th Advent Sunday | -7-5-7 | ||
| Christmas Eve | -7-6-6 | Christmas | |
| Christmas Day | -7-6-7 | was 25 Dec | |
| Boxing Day | -7-7-1 | was 26 Dec | |
| New Year’s Eve | -7-7/8-7 | depends on leap week |
See also[]
- Octalendar is similar, but has 8 months of 6 or 7 weeks.
- Some Academic Calendars also have 7-week or 8-week intervals.