Metronome & Instrument Tuner
Free, private and calculated in your browser
Metronome
Set a tempo, choose the meter, then start. The first beat is accented.
100
BPM · Moderato
Tap at least twice in rhythm to detect BPM. Audio uses look-ahead scheduling to remain stable when the UI is busy.
Instrument tuner
Play one sustained note at a time in a quiet room. The needle shows whether it is flat or sharp.
—
Waiting for a note…
Start the microphone and play a note
Standard guitar tuning
Detection range: 80–1200 Hz. Microphone audio stays in this browser tab and is never uploaded.
About this tool
Metronome & Instrument Tuner is a privacy-first utility designed to finish a small everyday task without an account, remote API or server-side data store. Inputs are processed in the browser and the visible result is available immediately, including when the calculation itself is performed offline.
The interface keeps the important caveats beside the result. Sensor readings are labeled as estimates, dates and financial projections expose their assumptions, and health or travel information includes a clear reminder to confirm decisions with an appropriate professional or official authority.
How to use
Choose a mode
Open the tool and select the measurement, calculation or study mode that matches your task.
Enter local values
Use the labeled inputs and sample values. Permission-based features request access only after you press their start button.
Review the result
Read the result and its limits. Time-sensitive tools use absolute timestamps so background tabs do not create drift.
Export or reset
Copy or download only when needed, and reset the form when you finish on a shared device.
Use cases
Quick personal workflow
Use it for a one-off measurement, conversion, study session or planning estimate without creating a profile.
Offline and private work
Keep notes, values and local records in the current browser session when connectivity or data sharing is undesirable.
Common mistakes
Mistake:Treating an estimate as a certified measurement or official decision.
Fix:Read the tool disclaimer and use calibrated instruments or official sources when accuracy has legal, medical or safety consequences.
Mistake:Leaving sensitive values open on a shared device.
Fix:Export only the information you need, then clear the form or close the private browser session.
Frequently asked questions
Related guides
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References & standards
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