Free Tool

SMS Length Calculator

Count characters as you type, see whether your message uses GSM 7-bit or UCS-2, and find out how many segments it will be sent and billed as. Then let AI help you fit it into fewer.

0Characters
GSM-7Encoding
0Segments
160Left in part

160 per SMS in GSM 7-bit.

TRY AN EXAMPLE

Start From a Sample Message

Pick a message to load it into the calculator. Notice how a single emoji or accented character can change the encoding and the segment count.

Marketing SMS

Notifications

Emoji & Accents

THE RULES

How SMS Length Is Calculated

Every SMS is 140 bytes. How many characters fit depends on the encoding, and the encoding is decided by the single most unusual character in your message.

GSM 7-bit
160characters in one SMS
153per part when split

Covers basic Latin letters, digits, common punctuation and a set of accented letters such as é, ü, ñ and à.

Extension characters count as two: € [ ] { } ~ | ^ \

UCS-2
70characters in one SMS
67per part when split

Used as soon as one character falls outside GSM 7-bit: emoji, Arabic, Chinese, Cyrillic and most other scripts, and typographic quotes like ’ and “.

Emoji and some rare characters take two units each, so they count double here too.

How many characters fit in one SMS?

A single SMS carries 160 characters in GSM 7-bit encoding, or 70 characters in UCS-2. Longer messages are split into parts of 153 (GSM 7-bit) or 67 (UCS-2) characters, because each part needs room for a concatenation header.

What makes a message switch to UCS-2?

Any character outside the GSM 03.38 alphabet, such as an emoji, most non-Latin scripts, or typographic curly quotes, switches the whole message to UCS-2 and cuts the capacity from 160 to 70 characters per SMS.

Why do some characters count twice?

Characters from the GSM extension table, such as € [ ] { } ~ | ^ and the backslash, are sent as an escape code plus the character, so each one uses two of the 160 positions.

Is the SMS Length Calculator free?

Yes. The live count, encoding detection and segment breakdown run in your browser for free, and the AI analysis is free to use as well.

AI ANALYSIS

More Than a Character Count

The count updates as you type. When you want to go further, the AI analysis explains the result and helps you cut segments.

Encoding check

Spots the exact characters that force UCS-2, such as emoji or curly quotes, and shows how much capacity they cost.

Segment breakdown

Shows how the message is split into parts, with the concatenation header and the bytes of each segment.

Cost and delivery

Explains what the segment count means for cost and delivery, with suggestions to bring it down.

Shorter alternatives

Suggests rewrites that keep the meaning and fit into fewer segments, or back into GSM 7-bit.

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