> For the complete documentation index, see [llms.txt](https://docs.formsort.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.formsort.com/adding-questions-and-content/question-reference/phone-number.md). # Phone number This question collects valid phone numbers from the responder. If the responder's input is not in the expected format, there will be an error message prompting to user to enter in a valid phone number. The answer to the number question is stored as number [data type](/response-data-collection-and-management/variable-schema.md#data-types). ## Showing input mask By enabling **Show input mask**, you can format the input from the responder as (000)-000-0000 when they are entering their phone number. ## International phone numbers **International** option allows the responder to enter in numbers outside of the U.S. phone format. If you enable this option, the responder will be able to choose from a list of countries and their respective prefixes (+90, +1, etc.). If you would like to change the default country phone number, you can enable the **Default country** option and pick a country from the menu. ## **Allowing multiple answers** Enabling **Allow multiple answers** lets the responder type more than one phone number as an answer to a question. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://docs.formsort.com/adding-questions-and-content/question-reference/phone-number.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.