Free hardware tester
DTMF Tone Generator: Phone Keypad Tones
Runs locally in your browser. Nothing is uploaded.
Web Audio tone controls
Generate a local tone, select its waveform and channel, and stop it instantly.
This is an uncalibrated output and routing tool, not a hearing test. Browser, device, amplifier, speaker, and room response all affect what reaches you.
Last updated: July 29, 2026
Dtmf tone generator: This DTMF tone generator creates the standard dual-frequency pairs for telephone digits 0 through 9, star, and pound, entirely with the browser’s Web Audio API.
How this DTMF tone generator works
Set playback volume low and select a keypad button. Each press combines one row frequency with one column frequency for half a second. The standard tone controls remain available for single-frequency comparison.
How to read the results
Each key is a pair, not one note. The rows use 697, 770, 852, and 941 Hz; the columns use 1209, 1336, and 1477 Hz. This page generates audio only and does not dial, call, transmit, record, or decode.
Common causes of failed tests
A decoder may reject tones because playback is distorted, clipped, compressed, too short, too quiet, routed through a voice-processing profile, or captured by a microphone with noise suppression.
Troubleshooting before you replace hardware
Use a moderate volume, sine output, a clean wired path, and disable voice processing when testing equipment you own. Do not rely on speaker-to-microphone playback for precise signalling.
For setup and buying context, see the tone generator, left/right speaker test, audio channel test, bass test, subwoofer test, and DTMF tone generator.
Frequently asked questions
What does DTMF mean?
Dual-tone multi-frequency: every keypad symbol combines one row frequency and one column frequency.
Does this page place a phone call?
No. It only generates local audio in the browser.
Which keys are included?
Digits 0 through 9, star, and pound are included.