SMS Length Calculator - Count Characters & Segments

Calculate SMS length, segments, and encoding (GSM-7/Unicode) in real-time. Optimize texts for marketing, avoid splits, and reduce costs. Works with emojis.

Your SMS message

Tip: Emojis or special characters switch encoding to Unicode and reduce the per-SMS limit.

0 / 160 (GSM)

Encoding	GSM-7
Characters	0
SMS Segments	1
Chars in last SMS	0
Max per SMS	160

US compliance reminder

Include clear opt-out instructions in marketing texts (e.g., "Reply STOP to unsubscribe."). Carriers expect immediate processing and a free confirmation reply.

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Frequently Asked Questions

Standard SMS messages use GSM-7 encoding and allow up to 160 characters. If your message contains Unicode or emojis, the limit drops to 70 characters per SMS.

When your text is longer than the character limit, mobile networks split it into smaller parts called segments. Each segment is billed like a full SMS. Long messages can therefore cost 2–3 times more than expected.

To avoid splitting, keep messages under 160 characters and use only GSM-7 characters. Even a single emoji or special character can switch your message to Unicode and reduce the limit to 70 characters, causing more splits.

This usually happens when your message contains hidden special characters (like smart quotes, symbols, or emojis). These trigger Unicode encoding, lowering the per-SMS limit and increasing total segments.

Yes. Emojis require Unicode encoding, reducing the limit from 160 to 70 characters per SMS. This means your message may use more segments, raising the cost — especially for bulk or marketing campaigns.

Longer or Unicode-encoded messages split into multiple segments, multiplying your sending cost. For bulk campaigns, this can significantly increase budget. Always check length before sending to keep costs predictable.

Stick to short, clear texts under 160 characters. Use GSM-7 compatible characters only. If branding requires emojis, plan for the extra cost and test messages with a length calculator before launching.

Yes. This tool shows real-time segment counts. Each segment is typically charged as one SMS credit by most providers, so you can estimate total cost before sending.

In the United States, marketing SMS messages must comply with CTIA and TCPA rules. Every campaign must allow recipients to opt out by replying with keywords such as "STOP," "UNSUBSCRIBE," "CANCEL," "QUIT," or "END." Carriers require businesses to process these requests immediately and confirm with a free opt-out confirmation message (e.g., "You have unsubscribed and will no longer receive messages.").

Yes. Best practice (and often required by carriers and laws) is to include clear opt-out instructions, such as "Reply STOP to unsubscribe." This ensures compliance with US regulations and protects your business from penalties.

100% private. Everything runs locally in your browser — no messages are uploaded or stored. You can safely check marketing drafts or personal texts without data risk.

GSM-7 is the default encoding that allows 160 characters per message. Unicode (UCS-2) is used when you include emojis or special characters, but it lowers the limit to 70 characters per SMS.

GSM-7 is the standard SMS character set supporting basic Latin letters, numbers, and common punctuation. It allows 160 characters per SMS. Extended characters like € or { count as 2 characters.

Emojis, non-Latin characters (Chinese, Arabic, Cyrillic), and special symbols force Unicode encoding, which reduces the limit to 70 characters per SMS segment.

Each segment is charged as a separate SMS. A 161-character GSM message uses 2 SMS credits. Carriers also use header bytes, reducing limits to 153 (GSM) or 67 (Unicode) per segment.

One character likely triggered Unicode encoding (like an emoji or smart quote). This drops the limit to 70, forcing a split. Check for hidden Unicode characters.

Messages over the single-SMS limit are split and reassembled by the recipient's phone. Each part includes header data, which reduces available characters per segment.

Stay under 160 characters for GSM or 70 for Unicode. Remove emojis to avoid Unicode. Use URL shorteners. Batch messages during off-peak if your provider offers discounts.

Yes. All emojis use Unicode encoding, which limits you to 70 characters per segment instead of 160. Consider using text alternatives like :) instead of 😊 for cost savings.

Avoid smart quotes, em dashes, and unusual punctuation that trigger Unicode. Stick to basic letters, numbers, and standard punctuation to stay within GSM-7 encoding.

Include clear opt-out instructions ('Reply STOP to unsubscribe'), honor opt-outs immediately, send confirmation, don't charge for opt-out messages, and only message people who opted in.

Yes, but use URL shorteners. A regular URL can consume 50+ characters. Shortened links (bit.ly, tinyurl) use ~20 characters, leaving more room for your message.

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