If you are performing a task that takes a certain amount of time or you are testing the speed of something – like the time that a computer takes to start up, or the time it takes to run a backup or complete any other time sensitive task, online timers are a great tool.

Online timers are mostly very simple and have a simply goal of just timing an event. But despite their simplicity they are extremely useful in many ways.


Of course you could also you lots of other devices to time how long something takes. You could use a watch, a wall clock or even your phone seeing as most phones these days have timers built in. But especially when you are timing how long something takes on your computer, using an online timer is just so convenient and it is probably the fastest way to time something because you don’t even have to move away form your computer screen. This is also ideal if you really need an accurate result. For example if you were timing how long it took to decompress a large file on your computer, having to move form the keyboard or mouse to click on “start” or “stop” on your phone would probably lose you half a second or even more – and that would ruin the accuracy of your results.

Whereas if you have the timer on the screen in front of you, then you can click to start the task you are going to time, and then click to start the online timer almost in the same movement – thus minimizing the room for error.

Accuracy of online timers

We wanted to test the accuracy of online timers, so we picked one at random – bestonlinetimer.com – in order to see how accurate it would be, compared to a phone.

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We used an iphone 5s and we used the standard timer function – starting from 0 and going up to 45 seconds. We used the online timer and we used the clock app on the iphone.

After 45 seconds the times were both completely in sync so we were able to confirm that the online timer was reasonably accurate (of course there could be minute discrepancies that would not show up until the timer was run for a much longer time, but its safe to assume that online timers are fairly accurate).

methods of creating online timers

There are actually many different methods of creating online timers, but they normally involve the use of one programming language or another. Javascript is a popular language with which to create online timers.

pitfalls of online timers

One of the problems with online timers can be the accuracy and this brings the question of how do you actually count the amount of time that has passed. there are calculations that can be used to achieve this, but they don’t work very well because they can be delayed depending on the load of the web server which is being used to run the code.

Creating an accurate online timer

code behind an online timerIn order to create an accurate online timer the program used to count time passed must make use of calls to the system clock – in other words, the program will query the system time of the server that it is running on over and over again – each time it queries the clock it will have another result returned of the exact time at each moment – from this information the exact time passed at each check point can be confirmed and relied upon.

So as you use an online timer, as each second passes by, the web page is actually making calls back to the physical hardware that it is running on, using a language that can keep executing itself in real time, and it is constantly confirming the exact time according to the web server, and then using that information to move the counter on to the next second/minute or hour in an accurate fashion.

As always with computing, a very simple task actually has some very complex computing requirements that make it work.