Message copy and segment calculator

SMS messages at Braze are charged per message segment. Understanding what defines a segment and how these messages will be split is key in understanding how you will be billed for messages and will help prevent accidental overages.

What is an SMS segment?

The Short Messaging Service (SMS) is a standardized communication protocol that enables devices to send and receive brief text messages. It was designed to “fit in between” other signaling protocols, which is why SMS message length is limited to 160 7-bit characters, such as 1120 bits, or 140 bytes. SMS message segments are the character batches that phone carriers use to measure text messages. Messages are charged per message segment, so clients leveraging SMS greatly benefit from understanding the nuances of how messages will be split.

As you create an SMS campaign or Canvas using Braze, the messages you build in the composer are representative of what your users may see when the message gets delivered to their phone, but is not indicative of how your message will be split into segments and ultimately how you be charged. Understanding how many segments will be sent and being aware of the potential overages that could occur is your responsibility, but we provide some resources to make this easier for you. Check out our in-house segment calculator.

Segment breakdown

The character limit for a stand-alone SMS segment is 160 characters (GSM-7 encoding) or 70 characters (UCS-2 encoding) based on the encoding type. However, most phones and networks support concatenation, offering longer-form SMS messages of up to 1530 characters (GSM-7) or 670 characters (UCS-2). So while a message may include several segments, if it does not exceed these concatenation limits, it will be viewed as one message, and reported as such.

It’s important to note that as you pass the character limit of your first segment, additional characters will cause your entire message to be split and segmented based on new character limits:

• GSM-7 encoding
  • Messages exceeding the 160 character limit will now be segmented into 153 character segments and sent individually, then rebuilt by the recipient’s device. For example, a 161 character message will be sent as two messages, one with 153 characters and the second with 8 characters.
• UCS-2 encoding
  • If you include non-GSM characters such as Emojis, Chinese, Korean, or Japanese script in SMS messages, those messages have to be sent via UCS-2 encoding. Messages exceeding the initial segment limit of 70 characters will cause the entire message to be concatenated into 67 character message segments. For example, a 71 character message will be sent as two messages, one with 67 characters and the second with 4 characters.

Regardless of the encoding type, each SMS message sent out by Braze has a limit of up to 10 segments and is compatible with Liquid templating, Connected Content, Emojis, and links.

• gsm-7 encoding
• ucs-2 encoding

Things to keep in mind as you create your copy

• Character limit per segment
  • GSM-7 has a 160 character limit for a single SMS segment. For messages with more than 160 characters, all messages will be segmented with a 153 character limit.
  • UCS-2 has a 70 character limit per message segment. For messages with more than 70 characters, all messages will be segmented with a 67 character limit.
    
    
• Segment limit per message
  • There is a maximum amount of segments you can send due to the medium’s limitations. No more than 10 segments of messages may be sent in a single Braze SMS message.
  • Those 10 segments will be limited to 1530 characters (GSM-7 encoding) or 670 characters (UCS-2 encoding).
    
    
• Compatible with Liquid templating, Connected Content, emojis, and links
  • Liquid templating and Connected Content may put your message at risk of going over the character limit for your encoding type. You may be able to use the truncate words filter to limit the number of words that your Liquid could bring to the message.
  • Emojis have no standard character count across all emojis, so make sure to test that your messages are segmenting and displaying correctly.
  • Links may make use of many characters, resulting in more message segments than intended. Though the use of link shorteners is possible, they are best used with short codes. Visit our SMS FAQ for more information.
    
    
• Testing
  • Always test your SMS messages before launch, especially when using Liquid and Connected Content as going over message or copy limits may result in additional charges. Note that test messages will count toward your message limits.

SMS segment calculator

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