SMS Pricing, Message Length, and Encoding Details

The cost of sending SMS is calculated per SMS sent and is invoiced on a monthly basis.

An SMS message has a maximum length of 140 bytes. Using a 7-bit character set, a single SMS can contain up to 160 characters. If a message exceeds 160 characters, it will be split into multiple 140-byte parts. Each part requires a header to indicate it's part of a concatenated message. This header uses at least 6 bytes, reducing the available space to 134 bytes per part, or 153 characters when using the 7-bit character set.

If the message contains characters outside the standard 7-bit character set, UTF-16 encoding will be used, requiring at least 2 bytes per character. This reduces the capacity to 70 characters for a single-part SMS, or 67 characters per part in a concatenated SMS. Some characters, such as emojis, may use up to 4 bytes. Additionally, certain characters within the 7-bit set require an escape character, which takes up 2 character slots.

In a multipart SMS using the 7-bit character set, escape characters and the following character cannot be split across message parts. Similarly, when using UTF-16 encoding, a character cannot be divided between message parts.

Note: The SMS standard specifies the use of UCS2 character encoding for 16-bit fixed-length encoding. However, UCS2 does not support emojis or characters from supplementary planes and has largely been replaced by UTF-16 in practice.

Disclaimer: This utility is designed to closely simulate how messages are processed by the LINK Mobility AS gateway. However, we cannot guarantee absolute accuracy. The results shown are intended as an illustration of how text is converted into SMS messages. This utility, along with the provided source code, is offered "AS IS," and we disclaim all implied warranties, including but not limited to implied warranties of merchantability or fitness for a particular purpose.