SMS Message Counter
Count SMS characters with GSM-7 and Unicode auto-detection. See exactly how many message segments your text will use.
Multi-part: 153 chars/segment
Multi-part: 67 chars/segment
About SMS Character Counting
GSM-7 Encoding
The standard encoding for SMS messages. Supports 128 characters including basic Latin letters, numbers, and common symbols. A single SMS can contain up to 160 GSM-7 characters. When sending longer messages, each segment holds 153 characters (7 are used for the concatenation header).
Unicode (UCS-2) Encoding
Used when your message contains characters outside the GSM-7 set, such as emojis, Chinese, Arabic, or special symbols. Unicode SMS is limited to 70 characters per single message, or 67 per segment for multi-part messages. One emoji can reduce your capacity significantly.
Extended GSM-7 Characters
Characters like [ ] { } | ^ ~ \ € are part of the GSM-7 extended set. They require an escape sequence, so each one counts as 2 characters toward your limit. This tool automatically detects and accounts for them.
Why Segment Count Matters
Most SMS providers charge per segment. A 161-character GSM-7 message costs twice as much as a 160-character one because it requires 2 segments. Understanding encoding helps you optimize costs when sending bulk SMS through APIs like Twilio, Vonage, or AWS SNS.
What this tool does
Estimate SMS segments under GSM-7 or Unicode encoding.
How to use it
Paste the message and inspect encoding, length and segment count before sending.
Worked example
160 plain A characters fit one GSM-7 segment; 161 require two concatenated segments.
Limitations and checks
GSM extension characters consume two septets. Emoji can use multiple Unicode units; carrier transformations and routing may affect actual billing.
How your data is processed
The operation runs in your browser. Copy and download actions use your device. Where Save work is offered, a local copy is stored; eligible work can sync only under your enabled account settings. See Privacy for site analytics and storage details.
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