Delete removes a pointer. The file stays on the disk, in the backup, in the cloud folder that synced it last week, and in whatever your colleague saved to their desktop. BurnKey starts from the other end. Every file is born encrypted, so destroying it means erasing the one key that opens it. Every copy that already left becomes permanent noise.
Three keys in a chain, so the thing you destroy is small, exact, and impossible to reconstruct from the copies.
Your passphrase derives a key encryption key through scrypt. That protects a random master key, and the master key seals one content key per file. Destroying a file erases its sealed content key and nothing else.
AES-256-GCM throughout, published and reviewed. No homemade algorithm, no secret scheme, nothing that depends on us being clever in private.
The passphrase never leaves the machine and we never hold a spare. A key that exists somewhere else can be requested, subpoenaed or leaked, so we do not keep one.
Every destruction issues an Ed25519 signed receipt you can verify yourself, so there is a record of what was destroyed and when, without the record exposing the content.
The point of key destruction is reach. A copy sitting in a cloud folder, an email attachment or somebody else's backup is ciphertext with no key. It stays there and it stays unreadable.
Enterprise rights management can already revoke a file remotely, and the vendor keeps a copy of the key to do it. BurnKey is that capability at consumer price with nobody holding a spare.
The Android app is built and in closed testing. It is not on Google Play yet, and we would rather say so plainly than call it launched.
The Android app is in closed testing now. We are looking for people who have had to ask for a file back and found out that asking is all you can do. Tell us what you needed destroyed and we will add you to the test.
