Live · knockknock.email

Your email is your
phone number

Call anyone, anywhere, free. No downloads. No phone number required. Just knock.

NEVER MISS A CALL

Knocking on someone's door is a basic human right. Anyone can walk up and ring the bell in good will. Knock Knock digitizes that right — if you know someone's email, you can reach them, anywhere in the world, free.

Built different.
By design.

No downloads

Works in any modern browser. Chrome, Firefox, Edge. Open a tab and you're live. No app stores, no installs, no updates.

No phone number

Your email address is your calling identity. Share it with anyone in the world. No SIM, no carrier, no geographic restrictions.

Free forever

Core calling is always free. No subscription required to call across the world. We'll add premium features later — the knock stays free.

Three steps.
One knock.

1

Sign in with your email

Enter your email address. We send a 6-digit code. That's your identity. No password, no account creation form, no personal data required.

2

Knock anyone by email

Type the email of the person you want to call and hit Knock. They get a real-time notification and an email link — no account required to answer.

3

Talk instantly, HD quality

When they answer, you're connected. HD audio via WebRTC — peer to peer, encrypted, no recordings. Like sitting next to each other, anywhere in the world.

Imran in DC knocking his Dad in Karachi — like they were sitting next to each other.

That is the product. No conference call link. No "can you hear me?" No downloading anything. One knock. One answer. Two people, one conversation, zero friction — no matter where in the world they are.

Built in 72 hours · March 2026 · United States

Ready to knock?

Free. No downloads. Works right now.

Get started free
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