--- title: "DTMF" slug: "flow-builder-dtmf" description: "The DTMF node enables caller data input. You can include an embedded recording of prompts describing the available key selections." tags: ["Call Flow", "Flow", "Inbound"] updated: 2025-09-19T12:22:55Z published: 2025-09-19T12:22:55Z canonical: "docs.voiso.com/flow-builder-dtmf" --- > ## Documentation Index > Fetch the complete documentation index at: https://docs.voiso.com/llms.txt > Use this file to discover all available pages before exploring further. # DTMF **Who should read this article**: Administrators The **DTMF** node enables caller data input. You can include an embedded recording of prompts describing the available key selections. ## Introduction Use the **DTMF** node to enable inbound callers to input data or make selections using the dial pad on their phones to make decisions about how they want their call routed. Tip In the **DTMF** node, specify an [audio message file](/v1/docs/flow-builder-dtmf#audio-file) that describes the key selections available in the **DTMF** node so that contacts can make a key selection without having to listen to the entire audio message first. ### Connections The **DTMF node** supports an unlimited number of input connections and up to 13 output connections. To add additional output connections, string together multiple **DTMF** nodes. ## Using the DTMF node To add a **DTMF** node to your interaction flow, click the **DTMF** node icon: ![Flow Builder DTMF Node](https://cdn.document360.io/44ae307a-3737-4fbf-98e0-9b888deb90dc/Images/Documentation/Flow%20Builder%20DTMF%20Node.png) The **DTMF** node supports a loop connection so that you can specify that a specific key press or an invalid key press repeats the node. ![Flow Builder DTMF Node Loop Connection](https://cdn.document360.io/44ae307a-3737-4fbf-98e0-9b888deb90dc/Images/Documentation/Flow%20Builder%20DTMF%20Node%20Loop%20Connection.gif) To make an input connection, drag a link from any node supporting an output connection to the **DTMF** node. To make an output connection, drag a link from one of the specified outgoing connections on the **DTMF** node to any node supporting an input connection. ![Flow Builder DTMF Node Making Links](https://cdn.document360.io/44ae307a-3737-4fbf-98e0-9b888deb90dc/Images/Documentation/Flow%20Builder%20DTMF%20Node%20Making%20Links.gif) ## Configuring the DTMF node To configure a **DTMF** node in your interaction flow, click the **DTMF** node to display the **DTMF node panel**. In the **DTMF node panel**, click the "i" icons to read information about the configuration menus and fields. ![Flow Builder DTMF Node Configuration Panel](https://cdn.document360.io/44ae307a-3737-4fbf-98e0-9b888deb90dc/Images/Documentation/Flow%20Builder%20DTMF%20Node%20Configuration%20Panel.png) ### Rename the node Beginning with the [September 15 - 19, 2025 release](/v1/docs/september-15-19-2025), you may name nodes in **Flow Builder**. Click a node in the node palette to add it to the flow. The node is added to the flow and is named **Node N**, where **N** represents the number of the node; for example, **Node 6**. Below the node name is the node type, such as **Play Audio**. Click the node to open the node configuration panel, then click the name of the node to edit it. Enter a new name, then the check mark to save your change. [Video](https://cdn.document360.io/44ae307a-3737-4fbf-98e0-9b888deb90dc/Images/Documentation/Flow%20Builder%20Renaming%20Nodes.mp4) ### Audio file To play a prompt of type *Voice message* when the interaction arrives at the **DTMF** node, click the **Audio file** menu and select an announcement from your [media library](/v1/docs/administration-media). The announcement could be a Prompt guiding the caller through the **[Select keys](/v1/docs/flow-builder-dtmf#select-keys)** options. ### Response timeout To specify the time to wait for the contact to select a [key](/v1/docs/flow-builder-dtmf#select-keys) after the prompt completes playing, enter a value in seconds in the **Response timeout** field. The default value is **5** seconds. The maximum value supported is **300** seconds. When the timeout interval and the [prompt repeat count](/v1/docs/flow-builder-dtmf#prompt-repeat-count) limit is reached, the interaction flow proceeds to **[Invalid input](/v1/docs/flow-builder-dtmf#invalid-input)**. ### Prompt repeat count To specify the number of times the **[prompt](/v1/docs/flow-builder-dtmf#audio-file)** should be played after the **[Response timeout](/v1/docs/flow-builder-dtmf#response-timeout)** has elapsed, set the **Prompt repeat count** to a value between **0** and **5**. If the **Prompt repeat count** value is set to **1** or more, the **Audio file** is replayed, and the **Response timeout** counter is restarted until the **Prompt repeat count** is reached. ### Select keys To specify which dial pad keys are valid menu option selections, click the key buttons. The **DTMF** node supports the following key presses: 0-9, *, #, and Invalid input. Each key press should correspond to an output link to another node. Each time you select a key, a corresponding **Key** point is added to the **DTMF** node. From each **Key** point, drag and output link to direct the interaction flow to the next node. ![Flow Builder DTMF Node Adding Keys](https://cdn.document360.io/44ae307a-3737-4fbf-98e0-9b888deb90dc/Images/Documentation/Flow%20Builder%20DTMF%20Node%20Adding%20Keys.gif) ### Dial by extension To enable contacts to dial the extension of the party they want to reach, select **Dial by extension**. When an extension is correctly dialed, the interaction flow ends. If the contact dials an invalid extension, the interaction flow proceeds to **[Invalid input](/v1/docs/flow-builder-dtmf#invalid-input)**. #### Digit timeout Use the **Digit timeout** field to specify the wait time between digits when a contact starts to dial an extension. The default value is **5** seconds. The maximum value supported is **30** seconds. When the timeout interval is reached, the interaction flow proceeds to **[Invalid input](/v1/docs/flow-builder-dtmf#invalid-input)**. Important If you have an overlap between the initial digit of phone extensions in your contact center and the valid key presses specified for the **[Select keys](/v1/docs/flow-builder-dtmf#select-keys)**, consider setting the **Digit timeout** value to no more than **3** seconds so that the contact does not have to wait too long after pressing a valid select key. ### Invalid input To specify what action should occur if one of the following conditions is met, drag a link from the **Invalid input** point to another node: - the contact presses a key that is not supported by the **DTMF** node - the contact does not press any key during the [response timeout interval](/v1/docs/flow-builder-dtmf#response-timeout) after the prompt repeat count is reached - the contact dials an invalid extension (if **[Dial by extension](/v1/docs/flow-builder-dtmf#dial-by-extension)** is enabled) ## Use Cases: Using the DTMF node with Play Audio nodes The **DTMF** node includes the option to specify an [audio file](/v1/docs/flow-builder-dtmf#audio-file) (2) that is played *every time* the call flows into the node. ![Flow Builder DTMF Node With Play Audio Use Cases](https://cdn.document360.io/44ae307a-3737-4fbf-98e0-9b888deb90dc/Images/Documentation/Flow%20Builder%20DTMF%20Node%20With%20Play%20Audio%20Use%20Cases.png) Tip The numbers 1 through 5 in this image are referenced by the following use cases. ### Playing different audio files to callers If you do not want to *replay* the audio file when a call loops back into the **DTMF** node (4 and 5), place a **[Play Audio](/v1/docs/flow-builder-play-audio)** node *before* the **DTMF** node in the call flow (1). This technique also lets you choose a different audio message to play for each input connection to the **DTMF** node (1, 4, and 5). ### Preventing callers from skipping the audio file If you configure an audio message in the **DTMF** node configuration panel, callers can skip the audio message by pressing a key on their dialpad. To *ensure* the caller listens to the whole audio message before making a key selection, do not configure an audio message as part of the **DTMF** node (2); instead, configure the audio message in a **Play Audio** node that is positioned before (1) the **DTMF** node. A message played to a contact to give them a choice of selections they can make or respsones they can give. A telephone extension refers to a number used to identify and dial a softphone, hardware phone, or queue within a contact center. ## Related - [Flow Builder Overview](/inbound-flow-builder-overview.md) - [Flows](/inbound-flows.md)