PairOnce

PAIRONCE ยท ABOUT

About PairOnce

PairOnce is a free browser tool that sends files, text and links between your devices. Open paironce.com on both, connect, and send: no app, no account, and no copy on a server.

What it does

PairOnce works between Windows, Mac, Linux, Android and iPhone, in 13 languages. Devices on one Wi-Fi find each other, and a QR code or six-digit code connects devices across networks. Everything is encrypted end to end. It also scans documents to PDF, shares a clipboard and shows a live picture between your devices, and AI agents can use it through a command-line tool.

Who runs it

PairOnce is operated by Yiheng Han, United States, as stated in the terms of service. It runs on Cloudflare, and Stripe processes Pro payments.

How it is funded

Sending files and messages is free, with no ads. The optional PairOnce Pro plan adds a monthly relay allowance, larger files and higher limits in the tools, and it helps pay for the service.

What is open

The protocol and threat model, the encryption and pairing library, the command-line tool and the release record are public on GitHub. Videos are on YouTube, and the command-line tool is on npm.

Contact

Last updated: November 7, 2026.