Free online timer for everyday use. Count up or down with alarms, loops, and flexible controls — perfect for quick tasks, reminders, and longer sessions. Features
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Free Online Timer
This is Timer123's general purpose timer — no pre-set time, no assumed use case, no configuration required. It starts at zero and does exactly what you need it to do. Count down from any time, count up to any time, run through zero into negative time, or loop continuously. Tap the space bar to start timing.
Built on a precision timing engine that measures real elapsed time rather than interval loops, the timer stays accurate under real-world conditions — browser load, tab switching, pausing and resuming. Twenty years of online timer development went into getting that right.
What This Timer Can Do
Most timers are built for one direction and one use case. This one handles all of them:
- Count down from any time — Set the start time to any value up to 99 hours and the stop time to zero. The timer
counts down and sounds the alarm when it arrives. Need to run all day? Enter
99has the stop time. - Count up from zero — Set the start time lower than the stop time and the timer counts up automatically. Set an
alarm at a specific elapsed time, or enter
99has the stop time to run open-ended for up to 99 hours. - Count through zero into negative time — Set the stop time to a negative value like
-5:00and the timer counts past zero and keeps going. Shows exactly how far over time a meeting, lecture, or session has run. - Count from negative to positive — Set a negative start time like
-1:00and a positive stop time like30:00to give setup time before a timed event begins. The timer counts up through zero and into the event window. - Loop continuously — Enable Loop and the timer resets and starts again automatically the moment it reaches the stop time. Useful for repeating intervals, recurring reminders, or any workflow built around a fixed cycle.
- Swap direction instantly — Click the swap button between the start and stop time fields to instantly reverse the two values. One click turns a countdown into a count-up and back again without retyping anything.
Setting the Time
The time input is deliberately forgiving — enter time in whatever format feels natural and the timer figures it out:
1:30:00or1.30.0or1 30 0— one hour thirty minutes1h 30mor90mor5400— all mean the same thing45sor45— forty-five seconds-5:00— negative five minutes for overtime or pre-event setup
Enter the value, click Set, and the timer resets to your new start time ready to go. No rigid format to memorize.
Controls and Shortcuts
- Space bar — Starts and stops the timer by default. Tap once to start, tap again to pause, tap again to resume. No mouse needed — works out of the box with no configuration.
- Reset — Stops the timer and returns to the start time. With AutoRestart on, Reset immediately starts counting again — useful for back-to-back sessions where speed matters.
- Keyboard shortcuts — Reassign Start, Stop, and Reset to any keys you prefer via Advanced Settings. Useful in presentations, classrooms, or hands-free situations.
- Fit Width / Fit Height — Scales the time display to fill the browser window. Combine with full-screen mode (
F11) for a display readable from across the room. - Click the title — Scrolls the page header out of view so the timer fills the available screen space. Click again to bring the header back.
- Save and share — Click the icon to copy a URL with all your current settings embedded. Anyone who opens that link loads your exact timer configuration instantly.
Timer — Common Questions
Does this timer work on phones and tablets?
Yes. The timer works on any modern browser across desktop, mobile, and tablet. The display scales automatically to fit your screen size. On mobile, tap the display area rather than using the space bar shortcut.
Will the alarm sound if I switch to another tab?
For reliable audio keep the timer visible in an active browser tab with the window not minimized. Browsers may throttle or mute background tabs, which can affect alarm playback. If the alarm matters, keep the tab in view.
How do I enter a time quickly?
Click the start time field and type in any format that feels natural — 25m, 1:30:00, 90 (seconds), or 1h 15m 30s all
work. Click Set and the timer resets to your new start time. No rigid format required.
Can I run the timer for several hours?
Yes. Enter 99h as the stop time to run the
timer for up to 99 hours continuously. The timing engine measures real elapsed time throughout, so accuracy holds over long sessions. Keep the browser tab visible and the window not minimized for best results.
Does pausing the timer lose any time?
No. Pausing preserves the exact time remaining or elapsed. Press Start again and the timer resumes from precisely where it stopped — not an approximation.
Can I use this as both a countdown and a count-up timer?
Yes. Set the start time higher than the stop time to count down;set it lower to count up. Use the swap button between the time fields to instantly reverse direction without retyping. If you primarily count down, the Countdown Timer is pre-configured for that. If you primarily count up, the Count Up Timer defaults to elapsed time display.
