Test left, right and both audio channels or alternate sides to identify headphone and speaker orientation. No microphone required; audio is generated locally.
⚠️ Lower your system volume before wearing headphones. This percentage is software gain, not sound pressure, and does not guarantee a safe loudness.
Ready
Left channel
Left channel
Right channel
Fixed 440 Hz sine tone · manual 3 s / alternate 9 s
Time remaining
Round
Uses the current system/browser output. Stop first, then change headphones or speakers in your system settings.
🔒 Audio is generated locally in your browser. No microphone access, recording, uploads or saved test history.
This identifies channels, not hardware faults or hearing ability. Mono settings, spatial effects, Bluetooth delay and speaker cross-talk may affect results. Both-channel mode is not a loudness comparison.
Not necessarily. Select both channels, center the system balance and check the connection and output device. This tool cannot diagnose hardware faults.
Check the L/R markings, wearing direction and speaker wiring, as well as channel-swap and spatial audio settings.
System mono output merges channels, and speakers mix in the room. Disable mono and spatial effects, then check with headphones.
Playback works in browsers supporting Web Audio, but routing and Bluetooth delay may affect what you hear and visual timing. This does not measure latency.
No. It generates a test tone without microphone access, recording or uploads. Change the output device in your system settings.
No. It controls software gain; system settings and hardware determine actual loudness. Lower system volume first. Both-channel mode is not calibration or a loudness comparison.
Test left, right and both audio channels or alternate sides to identify headphone and speaker orientation. No microphone required; audio is generated locally.
Audio is generated locally in your browser. No microphone access, recording, uploads or saved test history.
Browse this category: Image & Media
Test microphone input, live volume, peak level, clipping and waveform with a private 30-second local recorder. Audio never leaves your device.
Generate various audio waveforms, adjust frequency (Hz), metronome, and display visual oscilloscope animation.
Test your webcam, resolution, frame rate and camera switching with mirror preview, composition grid and private local snapshots.
Test mouse buttons, scroll wheel, click speed and double-click intervals with browser movement event estimates. All processing stays local.
