Online Alarm Clock

How to set an alarm

1. Pick the time. Depending on your device, the time box shows a 12-hour clock with a.m. and p.m. or a 24-hour clock. Your alarms are listed in 12-hour time either way.
2. Add a label if you like — "Leave for work", "Pick up the kids", "Medication". It appears on the screen when the alarm rings.
3. Choose a sound and press Test sound to check your volume before you rely on it.
4. Press Set alarm. The alarm appears in the list with the time left until it rings, such as "rings in 7 h 42 min".

You can set as many alarms as you want. Each one rings once a day at its time for as long as it is switched on and this tab stays open. Use Turn off to keep an alarm in the list without it ringing, or Delete to remove it.

When an alarm goes off, a full-screen message appears with two buttons. Stop silences it (the Escape key does the same). Snooze 5 min silences it and rings again five minutes later. If nobody responds, the alarm stops by itself after ten minutes.

Opening this page with ?time=06:45 at the end of the address fills in the time box for you, which is handy for a bookmark. It only fills in the time; you still press Set alarm.

What has to stay on for the alarm to ring

An alarm in a web page is only as reliable as the device it runs on. The page itself checks the time every second, but it can't ring if the browser or the computer isn't running.

Browsers slow down timers in background tabs to save battery. That can make a check land a little late, so this page rings an alarm whenever its time fell between two checks — up to five minutes late. An alarm that is more than five minutes overdue (for example, because the computer was asleep) is skipped rather than going off at a strange moment.

Three settings make a big difference:

• Keep my screen on. On browsers that support it (recent Chrome, Edge and Safari), this box stops the screen from switching off while the page is open. Plug a laptop in if you use it overnight.
• Notifications. If your browser offers it, the button under the alarm list lets this page show a system notification when an alarm rings while you're in another window.
• Volume. Check that the computer isn't muted, that the tab isn't muted, and where the sound will come out — Bluetooth headphones left connected are a common reason for a "silent" alarm.

For waking up on a phone, the phone's built-in clock app is the safer choice, because it can ring even when the screen is locked. This page is best for alarms during the day on a computer: a meeting, a pickup, a reminder to leave.

Alarms and Canada's time zones

The alarm uses the time and time zone set on your device, which is shown under the clock at the top of the page. If your device shows the right local time, the alarm rings at the right local time — whether you're in St. John's, where the clock is half an hour ahead of Atlantic time, or in Whitehorse.

If you travel with a laptop, its clock normally switches to the new time zone by itself. An alarm set for 7:00 a.m. rings at 7:00 a.m. wherever the device thinks it is. If the clock at the top of this page looks wrong, fix the time zone in your device settings rather than shifting the alarm.

The National Research Council of Canada keeps the country's official time with atomic clocks. Its web clock shows the official time in every Canadian time zone, so you can compare it with your device. Most computers and phones set themselves automatically using the Network Time Protocol; the NRC runs public time servers (time.nrc.ca and time.chu.nrc.ca) that it says can be accurate to a few milliseconds on a local network.

The night the clocks change

On Sunday, November 1, 2026, clocks fall back one hour at 2 a.m. in Ontario, Quebec, New Brunswick, Nova Scotia, Prince Edward Island, Newfoundland and Labrador and most of Nunavut. British Columbia, Alberta, Manitoba, the Northwest Territories, Yukon and Saskatchewan do not change their clocks this fall. The details by province are on our daylight saving time page.

Here is how alarms on this page behave around a clock change:

• Morning alarms ring at the new local time. An alarm set for 7:00 a.m. rings at 7:00 a.m. on the new clock, so you get an extra hour of sleep in the fall and lose one in the spring.
• Alarms between 1:00 and 1:59 a.m. on the fall-back night: that hour happens twice. The alarm rings the first time only, because each alarm rings once per calendar day.
• Alarms between 2:00 and 2:59 a.m. on the spring-forward night (Sunday, March 14, 2027): that hour doesn't exist where clocks change, and the browser moves the alarm an hour later, to the same minute after 3:00 a.m.

Your device changes its own clock automatically as long as automatic time and time zone are turned on. If you set a device's time by hand, you will have to change it yourself.

How much sleep to plan for

The Canadian 24-Hour Movement Guidelines recommend that adults aged 18 to 64 get 7 to 9 hours of good-quality sleep on a regular basis, with consistent bed and wake-up times. For adults 65 and older the recommendation is 7 to 8 hours. Working backwards from your alarm gives you a bedtime:

These are times asleep, so add the time it usually takes you to fall asleep. Keeping the same alarm time on weekdays and weekends is what the guidelines mean by consistent wake-up times. They are general guidelines for healthy adults, not medical advice; if you have ongoing trouble sleeping, talk to a health professional.

Your alarms stay on your device

Alarms are saved in your browser's local storage on this device, so they are still there when you come back to the page. Nothing is sent to us or anyone else, and there is no account.

That also means alarms don't follow you to another browser or device, and they disappear if you clear this site's data or use a private window. In a private window the alarms work while the window is open, but they are forgotten when you close it.

If you need a reminder for a date rather than a time of day — a payment, a deadline, a holiday — the countdown pages on this site count down the days for you, such as the CRA benefit payment dates.