Get a result now, see how it was made, and decide whether you need anything more.
Get a starting daily-water estimate from weight, activity, and climate.
Method: 33 ml per kg, with fixed additions for activity and hot weather.
Limits: Educational estimate only; it does not account for individual health conditions or medication.
See which published AHA category a pair of blood-pressure numbers falls into.
Method: Compares systolic and diastolic values against AHA cut-offs; the higher category wins.
Limits: Reference only, not a diagnosis, interpretation, or medical advice.
Start writing with one prompt when a blank page feels like too much.
Method: Selects one question from a fixed, hand-written prompt set.
Limits: It does not save writing, learn about you, or create a programme.
Play white, pink, or brown noise with a volume control and sleep timer.
Method: Generates sound in the browser with the Web Audio API.
Limits: No sound library or offline app controls; playback ends when the tab closes.
Instant and free: no account, trial, or payment is needed to use these four browser tools.
Your task inputs stay in the page: the calculator and checker work in browser JavaScript; the prompt tool has nowhere to enter an answer; and the player generates audio in the browser. They do not create a saved task history.
Know the boundary: health-related outputs are educational references, not personal medical guidance. The tool page explains its specific method and limit before you use it.
Each tool is complete enough for its stated task. You do not need to install an app, create an account, or join a mailing list to see the result. The related app links are optional paths for people who want an ongoing journal, record, reminder routine, or dedicated sound player.
If you need context before using a result, follow the guide linked from the tool page. Health calculators and category lookups explain their source and limitations, while journaling and sound tools explain what is generated locally in your browser.