Free Online 45 Minute Timer

Our 45-Minute Timer is setup to start with one click  Forty-five minutes is the natural length of a focused work session, a gym workout, or a class period  Long enough to go deep, structured enough to stay on track. When forty-five minutes are up, alarm sounds and you're done.

Our timing engine counts down using elapsed time rather than interval loops, keeping the 45 minute timer on time even when your browser is under load.

What Can You Do in 45 Minutes?

Forty-five minutes is a serious block of time — productive across professional, academic, fitness, and home contexts:

• Class periods — The standard school class period is 45 minutes in many countries.  Display the timer full-screen on a projector so students know how much time remains.
• Full gym workouts — A complete strength session, group fitness class, or sustained cardio block.  Use keyboard shortcuts to start without touching the screen, and set a strong alarm to cut through gym noise at the end.
• Deep work sessions — Longer than a standard Pomodoro but still bounded.  Forty-five minutes of uninterrupted focus on a single writing, coding, designing task, with a hard stop at the end.
• Cooking long intervals — Roasting a chicken, slow-cooking a sauce, or baking bread.  Set the alarm and step away without watching the clock.
• Therapy and coaching sessions — The clinical hour is often 45–50 minutes.  A visible timer keeps sessions on schedule without making the clock the focus.
• Study blocks for exams — Timed practice under exam-like conditions.  Set the timer, close distractions, and work until the alarm sounds
• Music practice — A focused 45-minute instrument practice session helps build consistent daily habits.
• Meetings and workshops — A hard 45-minute limit on a meeting forces tighter agendas and better preparation.  Display the countdown so everyone can see it.

Customize Your 45 Minute Timer

One click starts it as-is, but we give you control when you want it.  Open Settings to adjust:

• Start and stop time — The default is 45:00 to 0:00, but you can set any start and stop values within the supported range.  Count from 45:00 to -5:00 to give a session a visible overtime window, or from 0:00 to 45:00 to count up instead of down.
• Keyboard shortcuts — Assign Start, Stop, and Reset to keys of your choice.  Start a gym session or class period without touching the mouse, or stop mid-session from the keyboard.
• Time display format — Choose how the time is displayed.  For a 45-minute session, minutes and seconds gives a clear sense of progress throughout the countdown.
• Time display size and font — Adjust the size, font, and weight of the time display independently.  Scale it up for a projector or large monitor so it's readable from the back of a classroom or gym floor.
• Alarm sound and cycles — Choose from 50+ built-in sounds and tunes, or link to your own MP3.  Set the alarm to ring multiple times to cut through noise in a gym or busy classroom.
• Auto Restart — With Auto Restart enabled, pressing the Reset stops the timer, resets to 45:00, and starts counting down again.
• Save and share your setup — Configure once, then save and copy the URL via the icon under the timer display.  Share the link and your class or team loads the timer as you configured it.

I built the first version of these timers twenty years ago.  People kept using them, so I rebuilt them properly.  Users can finally link to their own alarm sound, which was the number one request all these years. There's no marketing budget here, so word of mouth helps people learn about them.  If this timer has earned a spot in your daily routine, mention it to someone who'd use it. https://timer123.com — John Whitney

45 Minute 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 to fit your screen size.

Will the alarm sound if I switch to another tab?

Yes — whether you minimize the browser window or place the timer on another tab, alarms should sound.

Can I control the timer without a mouse?

Yes.  Open Settings and assign keyboard shortcuts to Start, Stop, and Reset.  Once set, you can run the entire timer from the keyboard  This is helpful in a classroom, gym, or a situation where you don't want to fiddle with the mouse.

Can I make the timer count up from zero instead of down from 45?

Yes.  Set the start time to 0:00 and the stop time to 45:00 and the timer will count up.  Timer determines direction from the relationship between start and stop times.  There is no mode to select.

Can I add overtime to the timer?

Yes.  Set the stop time to a negative value — for example, -5:00 — and the timer counts through zero and continues into negative time.  Good for therapy sessions, lectures, or meetings where you want to see how far over time you've run.

How do I share this timer with my class or team?

Configure the timer — alarm, title, display, loop settings — then click the icon under the time display and copy the URL shown.  Anyone who opens that link loads the same setup.

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