---
title: "What Sleepyland is"
description: "Sleepyland is an open-source sleep publication and browser sound machine that synthesizes noise and procedural waves locally on this device."
canonical_url: "https://sleepy.land/about"
last_updated: "2026-08-29"
---

# What Sleepyland is

Sleepyland is a free browser sound machine. It synthesizes brown, pink, or white noise, procedural ocean waves, and an airplane-like rumble in the page. The generator uses no recorded or hosted audio files, product accounts, or server-side audio.

## What you can do

- Choose Sleep, Relax, or Focus. Each state is a distinct engine recipe with its own rhythm, spectrum, and movement.
- Use Gentle, Balanced, or Strong Energy. Energy scales movement depth and pace without changing volume.
- Open Tune for noise color, shared warmth, independent noise and wave levels, and wave pace.
- Run Endless, Countdown, or Focus Interval sessions.
- Watch the live post-mix spectrogram and spectrum curve, including an interactive tap-and-hold filtered-noise spectrum.

Settings stay in this browser. Selected mode and session kind can also appear as categorical fields in bounded anonymous production analytics. Read the [privacy page](/privacy) for what can leave the device.

## What Sleepyland is not

Sleepyland is not a medical device, diagnosis, or treatment. The names Sleep, Relax, and Focus describe intended listening contexts, not guaranteed outcomes. [Sleepyland Research](/) publishes sourced guides and states that the publication is educational, not medical advice. [Support](/support) does not provide medical advice, hearing-safety certification, or crisis services.

It is also not a supplement calculator. A [Hraness reading note on creatine and cognition](https://hraness.com/reading/does-creatine-make-you-smarter) records that the cognitive-enhancement case is weak: later trials and reviews point, at most, to a small uncertain mental benefit, and large effects in healthy adults are unlikely. Sleepyland does not recommend, dose, or track creatine or any other supplement. It generates sound in the browser.

## Who publishes it

[Hraness](https://hraness.com) lists sleepy.land among its public projects. The hosted product is free to use without an account. Sleepyland is [open source on GitHub](https://github.com/hraness/sleepyland) under the MIT License, and [research contributions are welcome](https://github.com/hraness/sleepyland/issues/new?template=research_correction.yml). The [license page](/license) records the exact reuse terms and third-party boundaries.

A silent [product demo](/demo) shows mode selection, Tune, playback, and the live spectrum. The [interactive sound machine](/noise) is the product itself.

A separate [reading note](/reading/good-ideas) discusses rest and attention as a condition for work, starting from Henrik and Johanna Karlsson’s essay on how new ideas are born. Another [reading take on habit and rest](/reading/habit-and-rest) starts from William James: a rest environment is not a habit until the first small act starts. A later [reading take on rest as a place where anxiety can become curiosity](/reading/anger-anxiety-agency) starts from Armin Ronacher.

## Sitemap

See the full [sitemap](/sitemap.md) for every public page.