TLDR
- Sparkle message length can be as long as Twilio limits (1600 characters). We try to keep all sparkle configurations to 2 segments (306 characters)
- Shout messages length is controlled by us and set to 2 segments (306 characters) by default. Please open a ticket with us change the segment limit.
Character counts for text messages are calculated by segment.
1 segment = 160 characters
2 segments = 306 characters (2 x 153)
3 segments = 459 characters (3 x 153)
Technical Stuff
The character limit for a single SMS message is technically 160 characters. However, most modern phones and networks support message concatenation: they split large messages into individual SMS messages (called "segments") and then re-create the large message at the receiving end.
Twilio's platform supports long messages up to 1600 characters across all Programmable Messaging channels, including SMS. However, for SMS messaging, Twilio recommends sending messages that are no more than 320 characters to ensure the best deliverability and user experience. See this article for details.
When you send an SMS message containing more than 160 characters, the message is split into smaller messages for transmission. Large messages are split into 153-character ‘segments’ and sent individually, then re-assembled by the recipient’s device. For example, a 161-character message will be sent as two messages: one with 153 characters and a second with eight characters.
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