ByHand for Gmail

Prove you typed your email yourself. One click in Gmail adds a small certificate that anyone can verify.

Anyone can generate AI slop email now. Which means an email you actually typed is worth something, if you can prove it. ByHand puts a "Certify by hand" button next to Send in Gmail. One click adds a small signature line to your email with a link to a public certificate. Whoever reads it can check that a human typed it. AI-generated text can't be certified. Edit the email after certifying and the certificate comes off. Certify again when you're done. PRIVACY No accounts, no tracking, no analytics. Your words never leave Gmail. A certificate holds a fingerprint of the message, a timestamp, and our signature. Nothing else. Policy: https://byhand.email/privacy $2 a month through Stripe. Unlimited certificates, cancel whenever. We donate the proceeds to artists who make things by hand.