About Simple Sleep

Plan your rest in your browser

Cycle length varies between people and throughout the night. We use 90-minute blocks only to plan times; the calculation does not identify actual sleep stages.

Core Features & Pillars

• Estimate times using approximate 90-minute blocks. The app does not measure sleep stages or guarantee a grogginess-free wake-up.
• Plan 20- or 90-minute rests and follow a countdown. Also set an alarm on your device.
• Estimate caffeine remaining from one drink using an average half-life. Effects on sleep vary individually.
• Audio Noise Synthesizer: Brown, pink, and white noise synthesized in real-time in the browser via Web Audio API, with zero network streaming or downloads.
• 100% Local Sleep Diary: Track your circadian consistency and perceived quality with private storage exclusively on your device (localStorage).

Part of the GoodTool Suite

Simple Sleep is part of GoodTool. Calculations and diary storage run in your browser; see the privacy policy for external resources.