Daylight saving time

The calculator determines the nearest DST transition dates for a given date. It also displays the time transition history for a given time zone.

This calculator allows you to find out whether a particular area uses daylight saving time at the moment or not. It also tells the history of time shifts for a given time zone.
Select a time zone (you can search by country or major city in the field to the right of the dropdown), select a date, and the calculator will show whether daylight saving time is active for this date, as well as the nearest dates of transition from/to daylight saving time.

PLANETCALC, Daylight saving time

Daylight saving time

 
:
:
Daylight saving time for a given date
 
Last time transition date
 
Next time transition date
 
The file is very large. Browser slowdown may occur during loading and creation.

Daylight Saving Time History

In 1784, Benjamin Franklin, being the US ambassador to France, published a humorous article in which he laughed at the nightlife in Paris. At the same time, he gave simple calculations that made it possible to save 96 million livres just by waking up early and using the sunlight of the sun instead of wax candles1:

In the six months between the 20th of March and the 20th of September, there are Total
Nights 183
Hours of each night in which we burn candles 7
Multiplication gives for the total number of hours 1,281
These 1,281 hours multiplied by 100,000, the number of inhabitants, give 128,100,000
One hundred twenty-eight millions and one hundred thousand hours, spent at Paris by candle-light, which, at half a pound of wax and tallow per hour, gives the weight of 64,050,000
Sixty-four millions and fifty thousand of pounds, which, estimating the whole at-the medium price of thirty sols the pound, makes the sum of ninety-six millions and seventy-five thousand livres tournois 96,075,000

A hundred years later, in 1895, New Zealand entomologist George Hudson presented his ideas for better use of daylight hours by shifting the time by two hours in March and October. The idea attracted attention, and Hudson issued an article describing it in detail in 1898. Unlike Franklin, Hudson was no longer jokingly focusing on economic sense, but on the benefits of additional light hours for the good and health of the population.

In this way the early-morning daylight would be utilised, and a long period of daylight leisure would be made available in the evening for cricket, gardening, cycling or any other outdoor pursuit desired.2

The idea received another impulse thanks to another lover of outdoor activities, the Englishman William Willett. He was an avid golfer and preached daylight saving time for the rest of his life. The first publication came out in 1907. Willett proposed to add 20 minutes four times every Sunday in April and back 4 Sundays in September. Willett predicted £ 2.5m savings in artificial lighting annually 3 :

# Total
During April 23 hours
During May, June, July and August 164 hours
During September 23 hours
Total 210 hours
210 hours at 1/10th of a penny per hour 1s. 9d.
43,660,000 people at 1s. 9d £3 820 250
Deduct, to meet all possible objections, including loss of profit to producers of artificial light, 1/3rd 1,273,416
£2,546,834

The article was published many times during Willett's life until 1915 (at least 19 editions). Despite the interest in the topic, old Europe was in no hurry to implement the idea.
The trigger was the First World War. Germany and its allies were the first to introduce daylight saving time on April 30, 1916, to preserve energy for the war effort. Not to be outdone, Great Britain followed on May 21, 1916, and other European countries have joined as well.
At the end of the war in Germany, daylight saving time was canceled, then reintroduced during World War II and canceled again at the end. But the UK continues to regularly and without interruption to transfer the clock hands to daylight saving time and back twice a year until now.
The calculator will allow you to track the entire history of daylight savings time for each country. To do this, you need to enable the "Time change history" checkbox and look at the table, which will contain the history of clock transitions in reverse chronological order.

Daylight Saving Time nowadays

Nowadays, artificial lighting expenses occupy a microscopic part in the structure of energy consumption. The positive effect on people's health of the daylight saving time is controversial. The disadvantages of shifting the clock twice a year are obvious. Russia, China, both Koreas, India, Japan, and other countries refused daylight saving time.
Since 2018, a bill has been introduced to the European Parliament to abolish daylight saving time. So if it were not for the pandemic, most likely, the law would have already entered into force, and daylight saving time would have ceased to exist in their historical homeland.
The widespread cancellation of daylight saving time is just a matter of time;)


  1. B. Franklin, Letter to the Editor of the Journal of Paris, 1784 

  2. G. Hudson, On Seasonal Time. TRANSACTIONS AND PROCEEDINGS OF THE ROYAL SOCIETY OF NEW ZEALAND, vol 31, 1898, 1898, page 577 

  3. W.Willett THE WASTE OF DAYLIGHT London, July, 1907 

URL copied to clipboard
PLANETCALC, Daylight saving time

Comments