How it works
Why send files as light?
Truly offline
No network path between the devices. Perfect for air-gapped or secure machines.
No Bluetooth, no pairing
Nothing to connect, nothing to trust. Just a screen and a camera.
No app to install
Runs in any modern browser, on the computer and on the phone.
Private by design
Your data never leaves the room. Nothing is uploaded anywhere.
Resilient
Fountain codes mean dropped frames don't matter — the file always rebuilds.
Open source
MIT licensed. Inspect it, fork it, run it yourself.
Love QR codes? Meet Codex QR
This tool turns files into QR codes. Codex QR lets you create beautiful, custom QR codes for links, menus, Wi-Fi, business cards and more — static codes that never expire and dynamic codes you can track and edit anytime.
Create your QR code →Frequently asked questions
How do I transfer files from PC to phone without internet?
Open Send on your computer and choose a file — the screen turns it into a stream of animated QR codes. Open Receive on your phone, point the camera at the screen, and the file rebuilds itself. No internet, Wi-Fi or Bluetooth is used between the devices; the data travels as light.
Does it work without Wi-Fi or Bluetooth?
Yes. There is no network path between the two devices. The sender only shows QR codes and the receiver only reads them with its camera — no Wi-Fi, Bluetooth, cable or pairing required.
Does it work phone to phone, or laptop to laptop?
Yes. Any device with a screen can send and any device with a camera can receive, in either direction — phone to phone, laptop to laptop, PC to phone or phone to PC all work the same way.
Is it private and safe?
The file never leaves the room. Nothing is uploaded to a server or the cloud, so it's ideal for air-gapped or sensitive machines.
How fast is it and how big can files be?
It runs at roughly 100 KB/s — best for documents, photos, keys, configs and small archives up to a few megabytes. Larger files work but take longer. The file is verified by hash on arrival, so it's either correct or it keeps going.
Do I need to install an app?
No. It runs entirely in your browser, on both the computer and the phone.