Overview
- Sinceerly, a Chrome extension built by Harvard Business School student Ben Horwitz, is now widely circulating online for rewriting polished text to look human.
- The tool offers three styles called Subtle, Human, and CEO that add typos, contractions, slang, and even all‑lowercase brevity to mimic real‑world writing habits.
- It runs free for a few tries before prompting a $4.99 payment to keep using it, according to multiple reports and the creator’s comments.
- Horwitz says an informal test cold‑emailing five Fortune 500 CEOs led to four replies, a claim shown in his social posts and reported by outlets but not independently verified.
- Reporters frame the project as a response to AI detectors and social norms that flag flawless prose as machine‑written, with Fast Company noting some marketers have seen higher open rates when typos suggest a real person wrote the message.