CyberJerry Seconds Calculators

General notes:

The Dogpatch (now CyberJerry) Seconds Calculators started out as a means of teaching myself javascript programming. The story really started some time ago, as the following historical synopsis illustrates:




1957-58 (??)


My older brother Jim teaches me that one billion is such a large number that no human can live to be a billion seconds old. This amazing fact wows me.

Sun. Apr. 15, 1979

Approx. 6:30 am CST

I realize that Jim's assertion is incorrect.

Sun. Apr. 15, 1979

Approx. 8:00 am CST

After calculating longhand one billion seconds in terms of years, days, hours, minutes, and seconds, I produce my first billionth birthsecond calculator: On one side of a single 8½ x 11 sheet of scrap paper, a sort of perpetual calendar table for determining one's billionth birthsecond, complete with adjustments for leap years.

1996 (?)


In DOS, I write a C program to calculate the difference in seconds between two dates & times. My primary focus is to easily compute a person's billionth birthsecond, and to watch one's personal seconds odometer tick by in real time.

Wed. Oct. 18, 2006


I write a letter to Jim, informing him that his assertion was inaccurate, and that he is about to turn two billion seconds old.

Wed. Nov. 01, 2006


Jim turns two billion seconds old.

Mon. Nov. 06, 2006


I receive a response from Jim thanking me for telling him how old he is.

Wed. July 11, 2007


I acquire a small personal website.

Mon. July 16, 2007


I begin to teach myself javascript, and decide to try creating a javascript version of my C seconds calculator.

Fri. Aug. 03, 2007

10:21 pm CDT

In response to two emails from my godson and nephew Chris, I send him an email with the link to my new javascript routine. The significance is obvious: Chris will soon turn one billion seconds old.

August, 2007


Through visit & emails, Chris helps me to uncover and fix several bugs in the beta version. He bookmarks the Calc 1 page.

Fri. Sep. 07, 2007

2:01:40 pm CDT

Chris turns one billion seconds old, becoming (perhaps) the very first human to observe his own personal birthsecond odometer roll over to one billion seconds, in real time.

Thu. Nov. 08, 2007

12:04 pm CST

Having worked out most remaining bugs, and attaining (more or less) broad compatibility and functionality, I upload the seconds calculators as finished release 1.0.000.




Mon. Dec. 3, 2007


Add e.g. buttons and data, and correct minor display boof for some time zone labels.

Tue. Jan. 1, 2008


Add Blogger and private user feedback links, to facilitate bug reports, suggestions, and other user comments.

Sat. Mar. 1, 2008


Fix calc #2 (It had start/end dates reversed [blush])

Tue. Mar. 4, 2008


Replace browser-dependent timezone and daylight saving logic with my own logic, for browser independence. Also dynamically refresh daylight saving status when date/time changes.

Fri. May 2, 2008


Fix daylight saving error in Now times (Calc 1,2,3, & 4).

Fri. Sept. 12, 2008


Correct minor timezone autoselect anomaly in Calc 5,6, & 7, and error message alignment in Calc 7.

Thur. Nov. 5, 2009


Add extra javascript diagnostics, and disable calculations for unreliable browser / javascript interpreters.

Holy Week, 2013


Blue Mountain Internet, apparently under new management, decides to trash the server hosting the Seconds Calculators, with no apology or amends. I can no longer in good faith recommend Blue Mountain Internet.

Fri. Apr. 12, 2013


In response to the above, move the Seconds Calculators to a better hosting site, and rename it CyberJerry Seconds Calculators. This represents a new release level, but no major changes in logic.

Wed. Mar. 19, 2014


Add leap second logic. Also fix a minor bug related to Dec. 31 of a leap year.

Tue. Nov. 18, 2014


Add Spanish translation.

Mon. Dec. 8, 2014


Minor textual corrections.

Thur. Dec. 11, 2014


More textual corrections.

Sat. Jan. 24, 2015


Add leap second for June 30 2015.

Mon. Feb. 09, 2015


For the Android onscreen keyboard (and other mobile devices?), restrict most fields to numeric input.

Mon. Apr. 13, 2015


Reformat layout for Android and other mobile devices.

Fri. June 19, 2015

2.3.001 -

Miscellaneous corrections.

Mon. June 29, 2015


Correct Windows compatibility problem.

Thu. Nov. 03, 2016


Add leap second for December 31 2016.

Tue. Jan. 03, 2017


Pre-stuff some variables for leap second logic.

Fri. Oct. 27, 2017


No changes. Just moved to a new site and new domain name.

Fri. Dec. 22, 2017

2.4.010 -

Miscellaneous corrections.

Tue. Nov. 26, 2019


Minor change to page layout; copyright (GPL) footnote.

Sat. Jan. 11, 2020


Rewrote blog article on my own website (See note below)

As the above suggests, the observance of one's billionth birthsecond is of particular interest to me. I have written briefly about it on one of my blog posts, if you're interested. (Well, even if you're not interested, I have in fact written the blog post.)

Of course, besides billionth birthsecond observance, the seconds calculators can be used in many other fun, interesting, and (who knows?) useful ways. Each form suggests an example for the calculation, and you may let your imagination invent others.

The only other general observation I can think of is that the whole idea of calculating seconds between two distant dates may be extremely impractical. Especially when you consider that, before the railroad era, there was no such thing as standardized time. Sure, we now have a standardized system of timekeeping and extremely accurate methodologies for defining and measuring time, but such was not the case before the modern era. The very definition of a second and its exact duration is a recent phenomenon. Ironically, just when we were getting used to the idea of standardized time and accurate timepieces, Einstein informed us that there really is no such thing as universally constant time. According to his theory of relativity, time is variable and relative to one's frame of reference, so the whole idea of calculating the precise quantity of seconds elapsed between two distant events is illusory.

For example, could anyone say exactly when 10:00 am occurred in Rome on March 15, 102 A.D.? Was there even a March 15 of that year? In fact, the people back then would not have referred to the year as 102. You see my point. But, then again, there was a point in time in Rome some 60+ billion seconds ago, and there was a date that would correspond, in our current calendar, with the 74th day of the 102nd year A.D., and there was a time, according to our present accurate timepieces, two hours before midday. If for some reason you want to ignore Einstein and calculate the exact number of seconds elapsed, here's the tool you need. No applause necessary.

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