This free tool converts non-GSM characters (smart quotes, em/en dashes, ellipses, accented letters, emoji, full-width characters) into GSM-7-safe text so your messages keep the 160-character limit instead of falling back to Unicode (70 chars). Perfect for developers using Twilio, Bandwidth, or other SMS APIs. It also shows accurate SMS segment counts for concatenated messages (153 septets per segment).
What is GSM-7 encoding? GSM-7 is the core SMS alphabet used by mobile carriers worldwide. Staying within GSM-7 maximizes your characters per message and keeps SMS costs low.
How are SMS segments calculated? Single messages allow 160 GSM-7 characters. Longer messages join into 153-septet segments. Unicode messages use 70 characters or 67 when concatenated.
What characters are converted by this SMS cleaner? Smart quotes, em/en dashes, ellipses, accented letters, emoji, full-width characters, and other non-GSM-7 characters are automatically converted to their GSM-7 equivalents.
Why did you build this SMS character converter? I created this tool out of necessity after sending bulk Spanish text messages using Google Translate through Twilio, Bandwidth, and other SMS providers. The translation included hidden Unicode characters I didn't catch, causing my SMS costs to be 5 times higher than predicted. This tool prevents that expensive mistake for developers using any SMS API.
Is my data secure when using this SMS tool? Yes, this tool runs entirely in your browser. No data is sent to any servers - everything is processed locally for maximum privacy and security.
What's the difference between GSM-7 and Unicode SMS? GSM-7 allows 160 characters per SMS, while Unicode (UTF-16) is limited to 70 characters. GSM-7 is the standard for most carriers and provides better character efficiency and lower costs.