Short messages sent between devices, often referred to as SMS messages, are the building blocks of text messaging. SMS messages are also the industry standard by which TextUs tracks usage. A message up to 1120 bits in size is equivalent to one SMS message, as determined by receiving carriers. For messages with no special characters or emojis, this is usually equal to 160 characters per SMS message. Messages larger than 1120 bits or longer than 160 characters are counted as multiple SMS messages depending on how many characters are used.
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When emojis or other special characters are used within a message, roughly 70 characters will equal one SMS message or 1120 bits in size. This is because the message is transmitted by the provider with a different encoding that allows the receiving device to translate the data into an emoji. While this encoding makes emojis and other special characters possible, it also means that even normal characters are larger in size. Therefore, a message with an emoji needs 70 characters or fewer to remain within the 1120 bit size limit. Additionally, because emojis are larger than normal characters, they typically count as two characters towards that 70 character limit.
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The SMS message count is also impacted by the use of rich media such as images or GIFs. A rich media attachment to a text message is equivalent to three SMS messages.
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All of the above SMS message parameters are aligned with standards for segments set by major texting providers.