DTMF Tools (Encode + Tone Generator)

Encode letters to keypad digits

Maps A–Z to phone keypad digits. Keeps 0–9, * and #.

Digits + playback

Tone (ms)

Gap (ms)

DTMF frequency table

Key	Low (Hz)	High (Hz)
1	697	1209
2	697	1336
3	697	1477
4	770	1209
5	770	1336
6	770	1477
7	852	1209
8	852	1336
9	852	1477
*	941	1209
0	941	1336
#	941	1477