croc

Send file

$ croc send [file]

$ croc send [file1] [file2] [file3]

$ croc send [directory/]

$ croc [code-phrase]

$ croc send --code [my-secret-code] [file]

$ croc --relay [relay.example.com:9009] send [file]

$ croc relay

croc [options] send [sendoptions] file_
croc [options] code-phrase

croc is a tool for securely transferring files between computers. It uses a relay server and PAKE (Password Authenticated Key Exchange) for end-to-end encryption, ensuring that transferred files cannot be read by the relay server or intercepted on the network.
The tool works across different networks without requiring port forwarding or firewall configuration. Users share a short code phrase, both parties connect to a relay server, and files are transferred through an encrypted channel. Local network transfers automatically use direct connections for faster speeds when possible.
Features include resumable transfers (if interrupted, transfers can continue from where they left off), support for sending multiple files and entire directories, cross-platform compatibility (Linux, macOS, Windows), and the option to run your own relay server for complete control.

--code phrase

Use custom code phrase

Specify relay server

Accept transfer without prompt

Output directory for received files

Overwrite existing files

Encryption curve (p256, p384, p521, siec)

Hash algorithm (xxhash, imohash, md5)

Disable compression

Disable local network transfer

Port range for local transfer

send

Send files or folders

Run a relay server

CROC_RELAY

Default relay server

Default code phrase

1. Sender generates code phrase
2. Both parties connect to relay
3. PAKE establishes encrypted channel
4. Files transfer through relay (or directly on LAN)

Default relay is public (croc.schollz.com). For sensitive transfers, run your own relay. Code phrases should be shared securely.

rsync(1), scp(1), magic-wormhole(1)