DTMF Tone Generator
Play authentic phone keypad sounds online. Each key produces real DTMF dual-tone frequencies used by telephone systems worldwide.
Press keys or use your keyboard (0-9, *, #)
DTMF Frequency Reference
Each key produces two simultaneous sine waves — one from each axis of the grid below.
| 1209 Hz | 1336 Hz | 1477 Hz | 1633 Hz | |
|---|---|---|---|---|
| 697 Hz | ||||
| 770 Hz | ||||
| 852 Hz | ||||
| 941 Hz |
How It Works
Press a Key
Click any key on the virtual keypad or press the corresponding key on your keyboard.
Hear the Tone
Each key plays two simultaneous sine waves — the exact frequencies used by real phone systems.
Play Sequences
Enter a phone number and play the complete DTMF sequence at your preferred speed.
Frequently Asked Questions
What are DTMF tones?
DTMF (Dual-Tone Multi-Frequency) tones are the sounds produced when you press keys on a phone keypad. Each key generates two simultaneous sine wave tones — one from a low frequency group (697-941 Hz) and one from a high frequency group (1209-1633 Hz). This dual-tone system was designed by Bell Labs to be resistant to false detection from voice or music.
What frequencies does each phone key use?
Each key uses a unique pair: the row determines the low frequency (1/2/3 = 697 Hz, 4/5/6 = 770 Hz, 7/8/9 = 852 Hz, */0/# = 941 Hz) and the column determines the high frequency (1/4/7/* = 1209 Hz, 2/5/8/0 = 1336 Hz, 3/6/9/# = 1477 Hz). The A-D keys use a fourth column at 1633 Hz.
Why do phone keypads use two tones per key?
Using two simultaneous tones makes the system extremely reliable. A single tone could be accidentally triggered by voice, music, or noise. The probability of two specific frequencies occurring simultaneously in normal audio is extremely low, making DTMF nearly immune to false triggers.
Can DTMF tones be used for phone menus (IVR)?
Yes, DTMF is the standard signaling method for Interactive Voice Response (IVR) systems. When you "press 1 for sales" during a phone call, your phone sends a DTMF tone that the IVR system detects and uses to route your call. Our generator produces the same authentic tones.
Is this DTMF generator free to use?
Yes, this tool is completely free with no limits. It runs entirely in your browser using the Web Audio API — no downloads, no sign-up required. Use it for testing, education, or fun.