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Sound Input Monitor

Leave it running and watch your microphone input over time. A scrolling history plots the peak and RMS level of every moment, while session stats track your loudest peak, average level, and any clips. Great for catching intermittent noises, level drift, or a one-off overload you’d miss on an instantaneous meter.

🔒 Runs entirely in your browser. No audio is recorded, uploaded, or stored.

Idle — press Start to begin monitoring.
Current
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Session peak
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Average (RMS)
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Clips
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Elapsed
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Input level history — peak (bar) and RMS (line), last 60 s · dBFS

What the Monitor Shows

An instantaneous level meter only tells you what’s happening right now. The Sound Input Monitor keeps the history, so you can leave it running during a recording, a call, or a practice take and review what your input actually did over the last 30, 60 or 120 seconds. Each vertical bar is a short slice of time; its height is the peak level in that slice, and the brighter line traces the RMS (average) level — the gap between them is your signal’s crest factor (how spiky it is).

Alongside the chart, the session stats accumulate from the moment you start (or last cleared): the loudest peak you hit, your average level, and a count of any clips. That makes it easy to catch problems an instantaneous meter hides — a single overload on a loud word, a fan that cycles on and off, or your level slowly drifting as you lean away from the mic.

How to use it

  • Catch intermittent overloads: if the clip count climbs even once, something briefly hit full scale — scrub the history to see when, and lower your gain.
  • Check consistency: a steady RMS line means an even level; a wandering one means you’re moving relative to the mic.
  • Spot environmental noise: bumps in the floor between phrases reveal fans, traffic, or handling noise.
  • Optional monitoring: turn on "hear yourself" (headphones only) to listen while you watch.

How this differs from the Gain Level Meter

The Mic Gain Level Meter is for setting your gain right now — peak-hold ballistics and a target zone. This monitor is for watching over time — a scrolling history and cumulative session stats. Use the gain meter to dial in, then leave this running to verify your input stays clean.

Frequently Asked Questions

What’s the difference between peak and RMS here?
Peak is the loudest instantaneous sample in each time slice — what determines clipping. RMS is the average level over the slice, which tracks perceived loudness. On the chart the bar is the peak and the line is the RMS; a big gap between them means a spiky, dynamic signal (high crest factor).
Why use this instead of a normal level meter?
A normal meter shows only the present moment, so brief problems vanish before you notice. This keeps a rolling history and cumulative stats, so a one-off clip, an intermittent fan, or gradual level drift is visible after the fact. Leave it running through a take and review it.
What do the session stats mean?
Session peak is the loudest single sample since you started or last cleared. Average (RMS) is the overall mean level across the whole session. Clips counts how many distinct times the signal reached digital full scale. Elapsed is how long the current session has been running.
Can I hear myself while monitoring?
Yes — click "Monitor (hear yourself)" to route your mic to your output. It’s off by default. Use headphones: on speakers the mic picks up its own output and you’ll get feedback. Monitoring uses the same in-browser path; nothing is recorded.
What does the history window length change?
It sets how much time the chart shows — 30, 60, or 120 seconds. A shorter window gives finer time detail; a longer one shows more of the session at once. Changing it clears the chart so the time axis stays consistent (session stats keep accumulating).
Why are the levels in dBFS?
dBFS (decibels below digital full scale) is the natural unit for a digital input — 0 dBFS is the maximum before clipping. A browser can’t measure calibrated dB SPL, so these are relative to full scale and depend on your input gain, which is exactly what you want for watching recording levels.
Does it record my audio?
No. The signal is metered in real time to draw the history and stats only; nothing is recorded, saved, or transmitted. The microphone is released when you press Stop or close the tab.
Does it disable auto-gain?
Yes — it requests the raw signal with auto-gain, noise suppression and echo cancellation off, so the history reflects your true input. If your OS forces auto-gain, you may see the level drift on its own; turn off microphone "enhancements" in system settings.

Related Tools

Mic Gain Level Meter
Set your input gain with peak-hold and a target zone.
Microphone Test
Quick check that your mic works: level, clipping, waveform.
Background Noise Detector
Measure your room/mic noise floor and find hum.
Mic Sensitivity Analyzer
Profile noise floor, speech level, SNR and dynamic range.
Noise Floor Analyzer
Octave-band Leq analysis of your noise floor.
Audio Spectrum Analyzer
Full FFT spectrum analyzer with weighting and peak hold.
← All Microphone Diagnostics Tools