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How many characters can I use per message?

A standard SMS message consists of up to 160 characters.

If longer, 153 characters per SMS are allowed (7 characters are used to merge the message). So, 161-306 characters require 2 SMS messages, and 306-459 require 3 SMS messages.

SMS messages are sent via the GSM-7 character set. Each character corresponds to 1 character:

The following characters are charged as 2 characters:
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The Unicode character set consists of up to 70 characters.

The Unicode character set is a character encoding system that allows you to send a much wider range of characters than standard Latin characters. It also allows for sending technical symbols and emojis.

Unicode encoding of a text message reduces the number of available characters to only 70, instead of the 160 allowed in GSM. Unicode characters require more space (2 bytes), instead of GSM characters that use only one byte.

All Unicode characters detected will cause the entire message to be sent as a Unicode SMS, reducing the number of available characters from 160 to only 70.

This can have a significant impact on SMS credit usage, so it is essential to check if your messages are being sent with the encoding standard (GSM or Unicode) that you intended.

Updated on: 22/02/2023