Nightwool

Calm & rhythm · Recording · Free in the app

Heartbeat sound

A slow, steady heartbeat. Set the pace anywhere from 40 to 100 beats per minute.

Timer

A 2-minute recording played in random overlapping segments, the way the app plays it, so you won't hear a loop. Start with your volume low. Keep this tab open.

About this sound

A slow, steady heartbeat: the soft double thump of a real heart.

One real beat is repeated exactly every second, giving a perfectly even 60 beats per minute, and four beats are stored as a loop that plays seamlessly. In the app you can set the pace anywhere from 40 to 100 beats per minute; it changes the playback speed, so faster beats also sound a little higher and slower ones a little deeper. The heartbeat is free in the app.

How people use it

Parents use a heartbeat to settle babies, and some adults find a slow pulse calming while winding down. For a baby, the cautious way is a low volume, the speaker well away from the crib and a timer rather than all night.

The app's Baby's Room mix layers it with a soft shush and white noise. For your own sleep, try a pace a little slower than your resting pulse and adjust by feel.

Questions

Does a heartbeat sound help babies sleep?

Some parents find it settles their baby, but the research is small. Keep it quiet, outside the crib and on a timer.

What heart rate should I choose?

There is no right number. The default is 60 beats per minute; try a few paces and keep the one that feels calm.

Is it a real heartbeat?

Yes, a real recorded beat, repeated so the rhythm is perfectly even.

Mix it with

Get heartbeat on your phone

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