The base unit for dates in this calendar is the hek, which is a hundred days (numbered 0 to 99).

Important note:

days and other units in the Hundred Days of Summer calendar are counted from zero.

A hek can be divided as follows:

 hek mont twee tweek 100 — — 33 33 34 50 50 7 7 7 7 7 7 8 7 7 7 7 7 7 8

A year or a sol has 11 monts, which makes it 366 or 367 days.

The monts of the year are Janel, Feble, Mahel, Aprel, Junel, Jewel, Augle, Seple, Octel, Novel and Decel.

Three sols make up a triol of 11 heks (numbered 0 to 10) or 1100 days. A date can be written as year number, hek number in the triol and day number in the hek.

There are 7 tweeks in a twee or 14 in a hek. A tweek begins on Sunday, numbered 0, and ends on Saturday, numbered 6. The last tweek of a twee has one more day: Sabado, numbered 7.

"Sábado" means Saturday in Portuguese from the word "Sabbath".

• A hek length of hundred days makes it easy to tell the distance between two dates, especially in hek notation
• Monts are very regular (three possible layouts)
• The tweek aligns to monts and heks every 14 tweeks

### Downsides

• A tweek can be one day longer than a week (every 50 days)
• A mont is longer than a month
• A year is longer than the solar year
• Only 11 monts in a year
• Dates deviate from the solar cycle by more than two weeks around leap years
• Variable length of the tweek can interfere with religious practices (see below)

## Month layout

The three monts that make up a hek have the following days and tweeks.

Mont 0
Su Mo Tu We Th Fr Sa Sb
0 0 1 2 3 4 5 6
1 7 8 9 10 11 12 13
2 14 15 16 17 18 19 20
3 21 22 23 24 25 26 27
4 28 29 30 31 32
Mont 1
Su Mo Tu We Th Fr Sa Sb
4 0 1
5 2 3 4 5 6 7 8
6 9 10 11 12 13 14 15 16
7 17 18 19 20 21 22 23
8 24 25 26 27 28 29 30
9 31 32
Mont 2
Su Mo Tu We Th Fr Sa Sb
9 0 1 2 3 4
10 5 6 7 8 9 10 11
11 12 13 14 15 16 17 18
12 19 20 21 22 23 24 25
13 26 27 28 29 30 31 32 33

## Leap year

The Hundred Days of Summer calendar year is too long by about one day.

To adjust, at defined interval a triol is replaced with a diol of two sols, with the second sol short of one mont (leap year). As a result there is no Decel on a leap year. A diol has 21 monts or 7 heks.

Sols in the leap year cycle are labelled with the letters of the alphabet. A leap year falls on letter W or letter Z.

Length of year cycles
diol triol W leap year cycle Z leap year cycle
sols 2 3 23 26
heks 7 11 84 95

The pattern of leap year cycles is:

Cycles
0 1 2 3 4 5 6 7 8 9
0 W W W W W W W Z W W
1 W W W W Z

There are fifteen leap years in a long cycle, for a total of 351 sols or 1282 heks.

The average length of the year is:

128200/351 = 365.242165 days

The beginning of cycle 0 was on 17 December 1446 (0 Janel 1447, or 1447A hek 0 day 0).

## Religious observances

Users of the calendar are encouraged to practice their religion on the designated tweek days, but there can be arrangements to accommodate people who are not comfortable with the change.

A small concession would be to allow a leave on Saturday instead of Sabado at the end of a twee.

A bigger concession would be to allow a leave on a traditionally designated week day instead of its tweek equivalent.

For example, supposing a religious leave on week day Saturday and a triol starting on week day Sunday (aligned with the traditional calendar), the progression of the leave through the triol would be: