Speaker Test
Check that both of your speakers work and are wired to the correct side. Play a tone to the left, right, or both channels, or run a frequency sweep. All sound is generated in your browser — nothing is uploaded.
Channel test
Put on both speakers or headphones. Each button should play only from the side it names — if left and right are swapped, your cables or audio settings need fixing.
Ready. Press a channel button to play a test tone.
How to use the speaker test
Start at a low volume — the slider defaults to 30% — and press Both to hear a centred tone from both speakers. Then press Left and Right in turn: each should come only from the matching side. This is the quickest way to catch swapped channels, a dead speaker, or a loose connection on one side. Because the first sound on a page needs a user action to start audio, nothing plays until you click a button — that's a browser rule, not a fault.
The pitch slider changes the tone's frequency, which is useful for hearing whether a speaker buzzes or rattles at particular notes. The sweep glides from a deep 100 Hz up to a bright 12 kHz over a few seconds; on healthy hardware it rises smoothly with no dropouts, and it doubles as a rough hearing check, since most adults stop hearing the very top of the range. Change the waveform to a square or sawtooth for a harsher, harmonically rich tone that can reveal distortion a pure sine hides.
If you hear nothing at all, make sure the correct output device is selected in your operating system, that system and browser volume aren't muted, and that headphones are fully seated. Press Stop at any time to silence the tone.
No sound on a call? Also check your microphone, and read our guide to common hardware faults and how to diagnose them.