When texting: Is 1 Byte 1 Character?

Nermal

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I think it's two bytes per character. One byte allows 256 different characters, and there are more than that available (consider that you can send a message in languages such as Japanese or Arabic if you wish).
 

Nermal

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Bah, you guys are too quick. I wrote something, realised it was wrong and deleted it, then edited it. That's how my post snuck in above without you seeing it :p
 

jav6454

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Nov 14, 2007
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I think it's two bytes per character. One byte allows 256 different characters, and there are more than that available (consider that you can send a message in languages such as Japanese or Arabic if you wish).
This is true for non English (or Latin based) languages. However, for regular ASCII, it holds that 1 char = 1 byte.
 

Nermal

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Dec 7, 2002
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This is true for non English (or Latin based) languages. However, for regular ASCII, it holds that 1 char = 1 byte.
Well, I guess it depends on whether the phone/network is clever enough to dynamically switch encoding based on what's been entered, or whether it'll do everything in "extended" (Unicode?) format.
 

mrsir2009

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Original poster
Sep 17, 2009
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This is true for non English (or Latin based) languages. However, for regular ASCII, it holds that 1 char = 1 byte.
Ah, and this would apply for a regular text message, yes?

----------

Well, I guess it depends on whether the phone/network is clever enough to dynamically switch encoding based on what's been entered, or whether it'll do everything in "extended" (Unicode?) format.
Goddammit you snuck in again :p

Anyway, on my old cellphone I think I remember it saying the number of bytes in a message as I wrote it. And I think, I think... it added one byte with every character I entered. Not certain though :eek:
 

KnightWRX

macrumors Pentium
Jan 28, 2009
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All these replies, no one bothered to look it up ?

Message size
Transmission of short messages between the SMSC and the handset is done whenever using the Mobile Application Part (MAP) of the SS7 protocol. Messages are sent with the MAP MO- and MT-ForwardSM operations, whose payload length is limited by the constraints of the signaling protocol to precisely 140 octets (140 octets = 140 * 8 bits = 1120 bits). Short messages can be encoded using a variety of alphabets: the default GSM 7-bit alphabet, the 8-bit data alphabet, and the 16-bit UCS-2 alphabet.[35] Depending on which alphabet the subscriber has configured in the handset, this leads to the maximum individual short message sizes of 160 7-bit characters, 140 8-bit characters, or 70 16-bit characters. GSM 7-bit alphabet support is mandatory for GSM handsets and network elements,[35] but characters in languages such as Arabic, Chinese, Korean, Japanese or Cyrillic alphabet languages (e.g. Russian, Serbian, Bulgarian, etc.) must be encoded using the 16-bit UCS-2 character encoding (see Unicode). Routing data and other metadata is additional to the payload size.
 

hafr

macrumors 68030
Sep 21, 2011
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All these replies, no one bothered to look it up ?
Unnecessary anecdote: I used to have a handset which, when set to use English, used up several characters in the character count when using letters like ç, but when set to French ç only equalled one letter in the character count.
 

sammich

macrumors 601
Sep 26, 2006
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Sarcasmville.
(this is really a tangent post)

^ says how many letters a message can be, but it doesn't say how much data is sent in total (including metadata). This mightn't be relevant to the question, since each message sent is a flat rate.

While I couldn't find actual any info on what data is sent alongside the SMS digest, this page shows what data is stored with a single tweet.
 

KnightWRX

macrumors Pentium
Jan 28, 2009
15,046
4
Quebec, Canada
This mightn't be relevant to the question, since each message sent is a flat rate.
Routing and metadata are not counted, but depending if you bust character count, your message could cost you extra as there is such a thing as concatenated SMS, which is a set of SMS messages that each represent a segment of the total message. Each segment could be charged as a seperate SMS since that is what it is. If your message requires segmentation for a concatenated SMS, your character count will be lower as an additional header is inserted right into the user data portion (7 bytes for 7 bit ASCII encoded messages, 8 bytes for 8-bit or 16 bit encoded messages.

If you really want to dwelve into the deep layers of GSM/SS7 signaling and message headers, there's always this page :

http://services.eng.uts.edu.au/userpages/kumbes/public_html/ra/sms/#Service Elements

Again, since this is the Internet and we have search services, I'm quite surprised it took over 10 posts before someone just bothered to look it up. Was this question even worthy of a thread ?

************************** comes to mind... I guess that's the new generation of "Internet users", they just browse forums and facebook...
 
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