The provisions of this chapter apply, unless otherwise provided, to the calculation of dates and periods specified in acts and regulations, judgments, or juridical acts.

If a period is fixed by hours, it shall commence immediately.
If a period is fixed by days, weeks, months, or years, the first day is not included in the calculation.

If a period is fixed by days, weeks, months, or years, it ends with the ending of the last day of the period.
If a period fixed by weeks, months, and years does not commence from the beginning of a week, month, or year, it ends with the ending of the day which proceeds the day of the last week, month, or year which corresponds to that on which it began to commence. But if there is no corresponding day in the last month, the period ends with the ending of the last day of the last month.

If an expression of intent is required to be made or a performance is to be effected on a specific date or within a specific period, and if the specific day or the last day of the specific period falls on a Sunday, commemoration day, or any other holiday, the day following the holiday takes it place.

The month or the year specified in this code is to be calculated in accordance with the official calendar.
If a period is fixed by months or years in such a manner that they does not calculate consecutively, a month is reckoned as thirty days, a year as three hundred and sixty-five days.

The age of a person is counted from his birthday.
If the month and the day of birth of a person are impossible to ascertain, he is presumed to have been born on the first day of July. If the month is known and the day is impossible to ascertain, he is presumed to have been born on the fifteenth day of the said month.