D Calendar Puzzle: find the day from a date in 10 seconds using powerful trick

The calendar puzzle: learn traits of dates and find the day from a date in 10 seconds

A syllabus for academic and competitive exams would be insufficient if it did not include date-and calendar-based techniques. We shall learn about the characteristics of dates and the way you can find the day from a date.

Find the day from a date


Assume for the moment that we are working in 2004.

The key that can be used to determine which day of the year 2004 any given date falls on is provided below.

KEY (1st Sunday of Every Month of the year 2004)









The box has twelve numbers in it. A month of the year is represented by each digit. Every digit in this key denotes a first Sunday of the month of the year 2004. 1st Sunday of the month January is represented by the number 4, 1st Sunday of February by the number 1, March by the number 7, and so on, until the last digit 5, which represents December.

Calculate the key for the full year:

Calculating the key for the full year is simple if you just commit the first Sunday of January to memory. How????

Since January 4th is a Sunday, you must add 4 weeks to January 1st to get next Sunday. Thus, 4 + 28 = 32. Jan has 31 days since then. Thus, the first Sunday falls on February 1st. Utilize this trick to calculate the key for the full year.

With the knowledge provided above, you will be able to forecast the day for any given day.

Case 1: Which day is January 7th?

Fourth of January is a Sunday, according to the key.

As a result, January 7 is a Wednesday.

Case 2: What day is August 3rd?

As August falls on the eighth month of the year, we utilize the eighth number found in the key. August is symbolized by the eighth digit, 1. It is recognized as the first Sunday in August. August 1st is a Sunday, so August 3rd is a Tuesday.

For Year 2021, let’s attempt this miracle.

Month Keys for the year 2021 are:

377, 426, 415, 375

Every digit in this key denotes a first Sunday of the month of the year 2021.

Case 1: On what day in 2021 is January 1st?
Key indicates that it is Sunday in January 2021 on the third. First Friday of January, then.

Case 2: What day is August 15, 2021?
Based on the key, on 1st August 2021 is Sunday, so 15th Aug is Sunday.

Seize this illusion or riddle: You just need to get the 1st Sunday of each month or the month you are predicting the day, for any year. And you’ll be able to predict day.

Magic For Leap Year

When the last two numbers of a year are divisible by 4, it is considered a leap year. This means that leap years are those that begin with 1904, 1908, 1912, 1916, 1920, etc.

Feature Set for Dates

Rule A (which covers every month of the year): An exact year consists of 52.1 weeks. That is to say, a year consists of fifty-two full weeks plus one extra week. As each year goes on, a date advances by one day due to this additional day. It will become a Monday in the next year if May 4 falls on a Sunday this year.

RULE B (which is applicable from March through December): We are aware that a date advances one day with each passing year. Therefore, if it is Thursday this year, it will fall on Friday the following year. Nevertheless, a date shifts by two days during a leap year.

As a result, if this year is a Thursday and the following year is a leap year, it will advance two days to become a Saturday. This occurrence occurs as a result of the leap year’s extra day pushing the date further forward. As such, it advances two steps rather than the usual one.

As an illustration, On July 8, 2005, Friday occurs. Next year on same date, it will be Saturday, in 2006, one step advanced. Sunday is when it happens in 2007. Going forward, it will take place on a Tuesday in 2008 (a leap year).

RULE C (which is relevant for January and February): A date that occurs in January or February often advances by one year with each passing year. But in the year after a leap year, it advances two steps.
For instance, January 4, 2002, falls on a Friday. In 2003, it will become a Saturday. In 2004, it will become a Sunday. In 2005, it will advance two days and become a Tuesday. This occurs as a result of 2005 moving two steps forward by succeeding the leap year 2004.

Now let’s start the magic.

Case 1: What day will it be on January 2, 2005, if December 31, 2000, is a Sunday?
The Sunday of December 31, 2000, is the answer. In 2001, 2002, and 2003, it will fall on Monday, Tuesday, and Wednesday, respectively. It will become a Friday in 2004. Therefore, it will be a Sunday on January 2, 2005, which is two days later.

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