Real SMS billing should include your compliance text. This calculator includes Reply STOP to unsubscribe by default so the segment count matches the message your recipients actually receive.
Opt-out Suffix (Carrier Compliance) None No suffix added STOP Suffix STOP:sheetsms.com/stop Unsubscribe Reply STOP to unsubscribe Custom Suffix Define your own
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Reply STOP to unsubscribe
Typed characters: 0 • Suffix characters: 27 • Total characters: 27
Characters 27
Segments 1
Encoding GSM-7
How it works Standard GSM-7 encoding allows 160 characters per segment. Special characters like emojis or accents force UCS-2 encoding. UCS-2 encoding limits segments to 70 characters. Long messages are split into multiple segments with headers (reducing usable space). For marketing and many business SMS flows, include opt-out wording such as Reply STOP to unsubscribe when estimating cost. Send SMS directly from Google Sheets Sheet SMS is the #1 add-on for sending text messages, scheduling campaigns, and managing conversations without leaving your spreadsheet.