SMS credit calculator

Learned the hard way on a 40,000 customers retention SMS campaign. Unicode inflated the count, so 25 paise became 75 paise. I built an SMS credit calculator to prevent this. Putting it out so you do not repeat my mistake. 🙂

SMS Credit Calculator

Message template

Assumed length per {#var#}

DLT defaults often cap each variable at 30 chars. Adjust if you know your longest value.

Appended text (optional)

Anything your gateway auto-adds is counted in credits.

Encoding

Credits (segments)

Characters counted

Per-segment limit

Why this many credits

Run “Analyze” to see triggers like Unicode characters and extended GSM-7 usage.

Recommendations

You’ll see actionable tips here, plus a one-click fix for common issues.

Detected risky characters

None yet.

Notes: GSM-7 fits 160 chars in 1 credit, concatenated segments 153 each. Unicode fits 70 chars in 1 credit, then 67 each. Extended GSM-7 characters like ^ { } \ [ ] ~ | € count as two.

SMS CREDIT CALCULATOR — QUICK GUIDE

Before you analyze
• Do not paste the curly placeholder token {#var#} in the message box.
• Use real sample values instead, or leave placeholders out and set “Assumed length per {#var#}” to your longest expected value.
• Remember: 1 credit = 160 chars on GSM-7, 70 on Unicode. Curly quotes, ₹, ellipsis, en or em dashes, emojis, and non-Latin text switch to Unicode. GSM-7 extended chars like ^ { } \ [ ] ~ | € count as two.
• Anything your gateway appends in the body also counts toward the limit.

How to use

Paste your SMS copy without {#var#}. Set “Assumed length per {#var#}” to your safest long value.
Add any auto footer in “Appended text”.
Click Analyze to see credits and the reasons.
Keep links short and trim text until the result shows 1 credit.