Some good online timers include Toggl, Tomato Timer and Timer Tab. Toggl is ideal for users who want to calculate their efficiency over time, while Tomato Timer works for breaking down time into smaller chunks. Timer Tab is good for users who need motivation to work quickly.
Toggl is also useful for freelancers, as it has the option to track time for the purpose of billable time sheets. It saves all tracked time in a user's account for later use. Tomato Timer periodically reminds users to take a break, while Timer Tab encourages a user to work against the clock to finish tasks more quickly than usual.