Encoding and segments
Why a message can cost more than one SMS.
An SMS carries a limited number of characters. Longer texts are split into segments and each segment is billed as one SMS.
| Encoding | Used for | One SMS | Per segment when split |
|---|---|---|---|
| GSM-7 | Latin letters, French accents in the GSM set | 160 characters | 153 characters |
| Unicode (UCS-2) | Arabic script, emoji, any character outside GSM-7 | 70 characters | 67 characters |
One character outside GSM-7 switches the whole message to Unicode. A French text with a single ê or â (not in the GSM-7 set) is counted at 70 per SMS.
The response to POST /v1/messages tells you the encoding and the number of segments charged.
Tips
- Keep order and code messages to one segment: shop name, order number, amount, one instruction.
- Darija in Latin letters stays in GSM-7; Darija in Arabic script is Unicode.
- Avoid emoji and typographic quotes, which force Unicode.