Cartoon: a visitor scans the KNOC QR code at a door, sends a short message, and the owner receives a notification and replies from their phone.

Three steps, start to finish

  1. Create a Door and print its code

    A Door is one place people knock: a front door, a gate, a studio, a reception desk. KNOC gives it a QR code you can print, stick up, or share. A free account includes one Door.

  2. A visitor scans and leaves a message

    Their phone camera opens a web page. No app, no account, no sign-up. They write a note, add a photo, or record a short voice message, and send it.

  3. You reply from your phone

    The knock arrives as a notification. Reply with text or your own voice message, and the visitor sees it at a private link. Your phone number is never shared with them.

What the visitor actually sees

A plain web page in their browser — the same thing that opens when any phone camera reads a QR code. There is nothing to install and no account to create, which matters when the person at your door is a courier with thirty more stops or a neighbour who has never heard of KNOC. It works on the phone they already have.

Text, photos, and voice

A visitor can send a written note, a photo, or a short audio message. You can reply with text or your own voice. How many messages a conversation holds, and how long past knocks stay visible, depend on your plan.

Live audio calls, in Early Access

On Doors where you turn it on, an eligible visitor can request a live audio call that rings your devices. This is Early Access: it needs a Pro plan, a per-Door setting you enable yourself, and a compatible browser, and it does not work on every device or network yet. Calls are audio only, capped at two minutes, and never recorded. If a call cannot connect, the visitor can still leave a message.

Where people put a KNOC code

Apartments where the building intercom does not reach your phone. Rentals and short stays, where an arriving guest needs a way to reach the host. Home offices and studios where the doorbell rings somewhere you cannot hear it. Gates and side entrances with no wiring. Small shops and workshops that are sometimes staffed and sometimes not. Anywhere someone needs to reach you at a door and installing hardware is impractical.

What KNOC does not do

There is no camera and no continuous recording. Visitors are not asked to create an account or a profile. Your phone number is not shared with them. Visitor submissions are deleted on the schedules set out in the Privacy Policy, and how long they stay depends on your plan.

Read the Privacy Policy

What KNOC is not

KNOC is not an emergency service — never use it to report one. It is not a monitored security system, and it is not a guaranteed replacement for installed hardware: it depends on phones, browsers, and networks that KNOC does not control. It is a way for someone at your door to reach you, and for you to answer.

Still deciding?

The help pages answer the questions that come up most, for owners and for visitors.

Read the help pages

Set up your first Door

One Door is free. Create your account on the web and print your code, or get the iOS app.

Create your KNOC  ·  Get the iOS app