The only tool that generates 5 proven subject line formats with Unicode bold that actually renders in Gmail, Substack, and Beehiiv inboxes β making your email impossible to miss.
Fill in the fields below β the more specific you are, the sharper your subject lines will be.
Type your newsletter topic above and 5 subject line styles will appear instantly β each with a plain version and a Unicode bold version that renders in real inboxes.
Open rates are won or lost in the inbox β before anyone reads a word of your content.
Unicode bold characters (πΉπΆπΈπ² ππ΅πΆπ) are actual characters β not formatting. Gmail, Substack, and Beehiiv display them as bold in the inbox list before the email is opened. No other styling trick does this.
Mobile shows only 35β40 characters before cutting off. Put your most compelling word or hook in the first 6 words. Everything else is a bonus. This tool shows character counts and mobile cut-off warnings.
The highest-performing subject lines create an information gap β they hint at something specific the reader doesn't know yet. "Why I stopped doing X" outperforms "5 productivity tips" every time.
The preview snippet shown after the subject is the second line of your pitch. It should complete the thought or deepen the hook β not repeat the subject line or trail off with email code artifacts.
Everything about subject lines that open and Unicode bold that renders.