Hermetic

Sealed envelopes for the internet.

Encrypt anything in your browser. Choose how it gets unlocked. We never see the contents — and neither does the network.

How it works
Drop
Sealed by link

Encrypt now, share via link. The decryption key lives in the URL fragment — never sent to a server.

Capsule
Sealed by time

Encrypt for a future date using drand timelock. Nobody can open it early.

Switch
Sealed by trust

Split the key across your trustees with Shamir Secret Sharing. Unlocks if you go silent.

Pact
Sealed by consensus

N-of-N agreement. Every party must sign before the seal opens. No quorum slack.

Halo
Sealed by hardware

Bound to a passkey or WebAuthn device. Only that hardware can unlock.

Beacon
Sealed by event

Unlocks when a chain event fires — block height, oracle reading, or contract state.

Echo
Sealed by reveal

Sealed bid auction. Bids stay hidden until the round closes; all open at once.

Sleeper
Sealed by command

Sits encrypted until the owner explicitly releases it. No timer, no link.

Mirror
Sealed by mutual disclosure

Two halves, two holders. Neither opens alone — both must combine.

Sigil
Sealed by proof

Unlocks when someone proves they know the answer — without revealing it.