About HeavySleeper
Key takeaways
- HeavySleeper is a free browser alarm for people who sleep through ordinary alarms: loud sounds, screen light, vibration and a short wake-up task.
- It runs in the open page. Keep the screen on and unlocked, and keep your phone's own alarm as a backup.
- It is a routine tool, not a medical service.
What is HeavySleeper?
HeavySleeper is a free web alarm that combines several wake-up cues. You set a wake-up time and choose a loud or gentle sound. You can add gradual screen light, vibration on supported phones, a task that gets you out of bed, and a follow-up check a few minutes later. There is also a sleep calculator and a wake-up guide.
What can it do?
| Part | What it does |
|---|---|
| Sounds | 14 built-in sounds, from Red Alert and Fire Bell to Birdsong and Soft Music, or your own file; the volume rises over 30 seconds to 5 minutes |
| Light and vibration | Screen light that brightens over 10, 20 or 30 minutes before the alarm (or off); vibration in browsers that support it (not Safari on iPhone) |
| Wake-up task | Three short sums, a six-digit room code you placed away from your bed, or no task |
| Follow-up check | A second alarm after 2 or 5 minutes that asks if you are still up |
| Sleep calculator | Bedtimes and wake-up times in about 90-minute cycles |
| Guides | Vibrating and bed shaker alarms, alarms that make you get out of bed and why an alarm did not go off |
What are its limits?
The page must stay visible and the screen unlocked; hiding, reloading or closing the page cancels the alarm. It cannot unlock a phone or ring in the background. The first alarm stops after 10 minutes without a response. Tasks do not prove that you are fully awake. Always keep your phone's own alarm as a backup.
Where do the sounds come from?
Most sounds are generated live in your browser by the site's own code with the Web Audio API. Construction Site uses "Noisy Construction Site" by Nqire and Heavy Traffic uses "Traffic, horns, engines, reverse beeps, truck, NYC" by TRP, both public domain (CC0) on Freesound, shortened to 30-second loops. Your own audio file plays only on your device and is never uploaded.
Who runs HeavySleeper?
HeavySleeper is run by Takreparation Skåne AB, Sparvgränd 6, 262 41 Ängelholm, Sweden (org.nr 556988-5931, VAT SE556988593101). CEO: Flemming Harboe Olsen. Flemming Olsen is a Swedish small-business owner who builds free web tools, and HeavySleeper is one of them. Contact: info@heavysleeper.app or +46 760 061 969, or see the contact page.
| Company | Takreparation Skåne AB |
| Address | Sparvgränd 6, 262 41 Ängelholm, Sweden |
| Org.nr | 556988-5931 |
| VAT | SE556988593101 |
| Managing director (VD) | Flemming Harboe Olsen |
| info@heavysleeper.app | |
| Phone | +46 760 061 969 |
How is the site paid for?
Some pages show ads from Google AdSense, which keep HeavySleeper free. Ads are placed away from the controls and results, so they are not clicked by mistake. In the EEA, the UK and Switzerland you are asked for consent before ad cookies are used; change your choice under "Privacy and cookie settings" at the bottom of every page. See the privacy page.
Frequently asked questions
Is HeavySleeper free? Yes. There is no account and nothing to buy.
Does vibration work on iPhone? No. Safari on iPhone does not support web vibration. Use the sound and light, or a dedicated vibrating alarm.
Can HeavySleeper fix my sleep? No. It helps you build a wake-up routine. If you often sleep through alarms or feel very sleepy in the day, talk to a doctor.