Sharing Secrets using Age

secret_sharing_using_age.md

Secret sharing using age

age is a simple, modern file encryption tool for sharing secrets via public-key encryption.

Install

macOS

brew install age

Windows

scoop install age

Verify:

age --version

Create a new key

• When someone wants to share a secret, generate a key pair and send them your public key.
• Create separate keys per context.

age-keygen -o age-key.txt

• age-key.txt contains your private key — never share it.
• The public key is printed to your terminal. Share only that line:

Public key: age1dnnrsy2yeevh7tpk007rkzj9kruk4j9kt3z3ywnqvynhzamvcuwql27jzm

Encrypt contents

• Get the recipient's public key.
• Put secrets in secret.txt, then encrypt:

age -o secret.txt.age -r age1dnnrsy2yeevh7tpk007rkzj9kruk4j9kt3z3ywnqvynhzamvcuwql27jzm secret.txt

Decrypt contents

• You have a .age file someone encrypted with your public key.
• Decrypt it with your private key:

age --decrypt -i age-key.txt ~/Downloads/secret.txt.age > ~/Downloads/secret.txt