SMS Segment Calculator
Count SMS segments online for free with real GSM-7 vs UCS-2 rules: 160/153 and 70/67 character limits, extension-character double counts, per-character warnings, and cost estimates.
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What is SMS Segment Calculator?
The SMS Segment Calculator applies the real GSM 03.38 encoding rules to your message text. It detects whether the message fits GSM-7 (160/153 characters per segment) or must switch to UCS-2 (70/67), counts extension-table characters as two units, lists exactly which characters forced the switch, and estimates cost from your price per segment.
Key Benefits
- Know the true segment count before sending a campaign
- See exactly which characters break GSM-7 encoding
- Avoid surprise costs from one emoji or Thai character
- Estimate total cost with your own per-segment price
- Private and instant - everything runs in the browser
Common Use Cases
- •Planning SMS marketing campaigns within a budget
- •Checking OTP and notification templates for encoding traps
- •Estimating costs for multilingual messages with Thai or CJK text
- •Auditing gateway bills against expected segment counts
How to Calculate SMS Segments
- Type the message: Enter the exact SMS text you plan to send, including spaces and punctuation.
- Set your price: Enter your cost per segment from your SMS gateway or plan.
- Check encoding and segments: See whether the message is GSM-7 or UCS-2, the billable length, and segment count.
- Fix encoding traps: Review the listed characters that force UCS-2, then rewrite if you need the cheaper GSM-7 rate.
Key Features
- Full GSM 03.38 charset plus the extension table
- Automatic UCS-2 switching when any character is outside GSM-7
- 160/153 and 70/67 segment limits applied correctly
- Per-character warnings with Unicode codepoints
- Cost estimate from your price per segment
- Instant results - all math runs client-side