SMS Byte Counter
Count message bytes to see whether it sends as SMS (90 bytes) or switches to LMS—Korean characters count as 2 bytes, ASCII as 1. Everything runs in your browser.
FAQ
What separates SMS from LMS?
Korean carriers send ≤90 bytes as SMS and larger messages as LMS (up to 2000 bytes) at a higher per-message rate.
Why are Korean characters 2 bytes?
Korean SMS traditionally uses EUC-KR, where Hangul takes 2 bytes—so an SMS fits 45 Korean characters.
What about emojis?
Emojis fall outside EUC-KR—they may break or force MMS conversion depending on the gateway. Check your provider's rules.
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