Why can only send 70 Chinese characters or 160 English in a short message?

① Limited by communication technology. The amount of text information sent by a single short message is limited to 160 English characters or 140 bytes of binary information, that is, 70 Chinese characters (including punctuation marks), in which punctuation marks are also Chinese characters.

② Conversion of characters. English characters are encoded in 7-bit ASCII, while Chinese characters are encoded in 8-bit UCS-2, accounting for 2 bytes, so 160 English characters are converted in 7-bit ASCII, that is,160x7 =1120 bits; Chinese characters are coded according to 8-bit UCS-2, that is, 8 bits are one character, and one Chinese character accounts for 2 characters. 1 120 bits are converted into Chinese characters, that is, 1 120/8/2=70.

(3) the operator's charging standard. Nowadays, many mobile phones support sending long short messages, which are often charged according to 70 Chinese characters (or 160 English characters). For the receiver, if the mobile phone supports the long short message function, it will display the complete long short message content, otherwise it will be displayed in strips.