The GSM characterset

What is the GSM character set?

The GSM-7 character set is a collection of the most commonly used letters and symbols that are used to send SMS. 

The letters include most of the characters that are used in most Latin based languages.

It also includes all digits from 0 – 9.

Here’s the full list of characters.

GSM charactset letters numbers symbols

There’s also an extension set of symbols that you can use. These use 2 characters as opposed to one

\   ^   {   }   [   ~   ]   |   €

What does GSM stand for?

GSM stands for Global System for Mobile communications.

How long can a text be using the GSM character set?

A standard text using GSM-7 is a maximum of 160 characters. You can send longer messages which will be sent a 2 separate texts and will appear as one text on the user’s phone.

These longer texts are known as concatenated texts.

Note that if you use characters or emojis that are not in the GSM character set, your text will be sent as unicode and you only have a maximum of 70 characters per text.

Related articles

What is unicode? GSM’s unruly cousin that can cause you to spend more that you intended sending SMS.

What is SS7? Deep into SMS infrastructure here with a simple explanation of SS7

What’s the maximum length of text message? Is there a maximum and what is it?

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Henry Cazalet Managing Director
Co-founder and Director of The SMS Works, a low cost and powerful SMS API for developers. About Henry