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SMS/MMS Message Length

Message Content Length

  • GSM7 (7-bit) = 160 characters maximum. For longer multipart messages, a User Data Header (UDH) is added to the message to instruct the receiving device on how to reassemble the message, resulting in a maximum of 153 characters for the body of the message.

Supported by standard English letters, numbers, and common symbols.

Hello John! Your appointment is confirmed for tomorrow at 10:30 AM. Please reply YES to confirm or call us at 800-xxx-1234 if you need assistance

Character count: 160

  • Latin1 (8-bit) = 140 characters maximum. For longer multipart messages, a User Data Header (UDH) is added to the message to instruct the receiving device on how to reassemble the message, resulting in a maximum of 134 characters for the body of the message.

Typically used for Western European languages containing accented characters such as é, à, ü, ñ, etc.

Bonjour André, votre réservation est confirmée. Présentez-vous à 14h00. Merci et à bientôt. Café réservé pour vous.

Character count: Approximately 140

  • UCS-2 (16-bit) = 70 character maximum. For longer multipart messages, a User Data Header (UDH) is added to the message to instruct the receiving device on how to reassemble the message, resulting in a maximum of 67 characters for the body of the message.

Used when the message contains Unicode characters such as Chinese, Japanese, Korean, Arabic, Hindi, or emojis.

Example using Hindi:

An example close to the 70-character limit:

नमस्ते! आपकी अपॉइंटमेंट कल सुबह 10 बजे है। कृपया समय पर पहुँचें। धन्यवाद।

Character count: Approximately 68–70 Unicode characters

Any message segment which has been broken up from a single message due to length will be treated as a single message, as will be messages to multiple recipients.

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