Free Sleep Timer with Automatic Fade-Out

A sleep timer plays soothing background sounds while you drift off, then gently fades them to silence once you're asleep. Lull's sleep timer is a free, browser-based tool that fades out white noise, rain, and other ambient sounds after a duration you choose — no app to install, no sign-up, and no ads.

Why Use a Sleep Timer?

Background sound is one of the simplest ways to fall asleep faster. It masks sudden noises — a barking dog, traffic, a snoring partner — that would otherwise jolt you awake. But leaving sounds playing all night isn't always ideal. Some people find continuous noise disrupts the deeper stages of sleep, and a phone or speaker running for hours wastes battery.

A sleep timer gives you the best of both worlds: the calming effect of sound while you fall asleep, and a quiet room once your body has settled into rest. You get the masking benefit during the most vulnerable transition — falling asleep — without committing to eight hours of audio.

How Lull's Sleep Timer Works

Lull is built around a simple, distraction-free timer. Open the app on any device and switch to the Timer tab. You'll see quick presets and a custom duration field:

• Quick presets: tap 15, 30, 45, or 60 minutes for one-tap setup.
• Custom duration: enter any value from 1 to 600 minutes for a timer that matches your routine.
• Gentle fade-out: rather than cutting off abruptly, the volume eases down to silence so the change never wakes you.

Start any combination of sounds — rain layered over white noise, ocean waves with a soft fan — then start the timer. Lull remembers your mix while the countdown runs and fades everything out smoothly when it ends.

How Long Should Your Sleep Timer Be?

Most healthy adults fall asleep within 10 to 20 minutes, so a 30-minute sleep timer is a sensible default for most people. If you tend to lie awake longer, 45 to 60 minutes gives you a comfortable buffer. Use shorter timers (15 minutes) for daytime naps so you wake up before entering deep sleep and avoid grogginess.

If you live in a noisy environment or wake easily during the night, you may prefer to skip the timer and let sounds loop all night instead. Lull supports both approaches — the timer is there when you want it, but it's never required.

Tips for Better Sleep with a Timer

• Keep the volume low. Sleep sounds should sit just at the edge of awareness — around the level of soft rainfall — to mask noise without becoming a distraction.
• Pick a sound you won't notice. Steady, unchanging sounds like white noise, pink noise, or a fan are easier to ignore than music or speech.
• Pair the timer with a morning alarm. Lull includes a full alarm clock, so you can fall asleep to rain and wake up to a gentle chime.
• Use a wake lock overnight. If you skip the timer and play sounds all night, enable Lull's wake lock so your device doesn't suspend playback.

A Free Sleep Timer, No Downloads Required

Lull runs entirely in your browser and generates every sound in real time — there are no audio files to download and no streaming. It works on phones, tablets, and laptops, and you can install it as a progressive web app (PWA) for offline use. Whether you need a sleep timer for tonight or a reliable nightly routine, Lull is ready the moment you open it.