# Encoding ## Message body Messages sent with the REST API are divided into one or more SMSs. The message body, which is represented by the Text parameter, is encoded using UTF-8. When only GSM characters1 are used the maximum size of a single SMS is 160 characters. For longer messages the API will automatically split the text into multiple SMSs, each with a maximum of 153 characters. When characters not represented in the GSM 03.38 are used, the message body will be encoded using UCS-2 (UTF-16 Big Endian) and the maximum size of each SMS is 70 characters. The API will split the message into several SMSs of maximum 67 characters. > A long message split into multiple SMSs are automatically interlaced on the receiving device and shown as one message. ## Phone number formats All phone numbers should be given in international format, see E.164 and NANP. MSISDNs (phone numbers) should start with +, e.g. +46707659443. If part of an URI the + shall be omitted, e.g. 46707659443. --- # Agent Instructions: 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: ``` GET https://docs.ebbot.ai/ebbot-docs/developer-resources/ebbot-chat/sms-api/encoding.md?ask= ``` The question should be specific, self-contained, and written in natural language. 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.