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Tool to decrypt/encrypt DTMF codes. Dual-tone multi-frequency DTMF codes are combinations of sound frequencies used in phones when dialing numbers.

Answers to Questions

What are DTMF Codes? (Definition)

A DTMF code for dual-tone multi-frequency, is the name given to a combination of sound frequencies (beep) emitted by the keys of a telephone keypad. They are used by voice servers and for dialing numbers.

How to encrypt a number using DTMF Codes?

DTMF codes are used by phones and can be used to substitute numbers with their sound wave frequency as described in the table:

1209 Hz

1336 Hz

1477 Hz

1633 Hz

697 Hz

1

2

3

A

770 Hz

4

5

6

B

852 Hz

7

8

9

C

941 Hz

*

0

#

D

Example: To crypt DC0D3, look for D which is the combination of 941Hz and 1633Hz, then write it 1633-941 (or 941-1633). The complete ciphered message is 1633-941/1633-852/1336-941/1633-941/1477-697

How to decrypt Codes DTMF cipher?

Decryption is a simple reverse substitution, for each frequency, a digit or a letter is associated.

How to recognize DTMF Codes?

There are only 8 frequencies: 697 Hz, 770 Hz, 852 Hz, 941 Hz, 1209 Hz, 1336 Hz, 1477 Hz and 1633 Hz.

What does DTMF means?

DTMF stands for dual-tone multi-frequency and translates sometimes into Vocal Frequencies.

Source code

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