DTMF Code

Short for Dual-tone Multi-frequency Code, it is a response code generated when an end-user presses the numbers on a mobile or landline phone’s keypad.

Each number from 0 to 9 is uniquely identified with a DTMF code that can be received and interpreted on the receiver side. DTMF code signaling enables reception of information from the end user e.g. PIN codes during a voice call.

How are DTMF codes used in the telecom industry? 

Today’s mobile telephones use a digital process for standard calling and messaging, so DTMF codes are not used when connecting to the mobile network base station. However, they do support DTMF codes for a number of important use cases:

• Entering pin codes as part of 2FA or 3FA authentication solutions
• Entering credit card details over the phone
• Navigating automated telephone menu systems
• Integrations with older telephone systems