One of my favourite timers is a countdown timer here. You can show it full-screen, set any time you need and use Pause if you see that more time is needed. When the time is up, it rings like an old-fashioned alarm clock and the display starts blinking.
The site has a large variety of timers and you may try several before you know which you like best.
Another simple timer is here. You can choose the background colour of the screen, the size of the digits (which is this timer's best feature if you want to use it in a big room) and set the time limit. However, you cannot set your own time, you must use the pre-set time intervals. Not a big problem though, there is a choice of any number of minutes up to 1 hour.
here and it shows minutes and seconds written in numbers and letters like this - 1 minute 20 seconds, not a clock face, which is boring if you ask me. On the other hand, if the students are busy doing their task, they will not pay much attention to the screen. The good thing is that the e.ggtimer gives a beep and shows time expired on the screen.
alarm clock which does what it says - it wakes you up. It works like a true alarm clock - you set the real time and choose what sound you would like to hear - cockerel, classic clock, electronic, military trumpet or slayer guitar (impressive!), then forget about it and jump when it starts ringing.
You can read about one more countdown timer which I have described before. Check it out here.