almin™ Seal is a free, single-file, browser-based tool that seals files against today's attackers and tomorrow's quantum computers, without any quantum hardware of its own. It runs entirely in your browser. Nothing is uploaded, ever.
Open almin™ Seal (free)→No quantum computer today can break the encryption protecting your files. True, and beside the point. An adversary who cannot break your encryption today does not need to. They can copy the encrypted file, store it, and wait. Storage is cheap. The file only needs to still matter when the wait is over.
“The lock on the front door can be excellent; it doesn't matter if someone can walk in through a window a quantum computer will eventually open.”
Grover's algorithm only halves AES-256's effective strength to ~128 bits, still far beyond any foreseeable attack. The vulnerability is entirely in how the key gets agreed.
NIST finalised its first post-quantum standards in August 2024. Chrome, Firefox and Cloudflare deployed hybrid post-quantum key exchange in production TLS before that.
A conventional breach has a knowable window. Harvest-now-decrypt-later has none: the capture happens quietly today; the exposure crystallises years later, for everything at once.
The difference is not a technicality. It decides what hardware you need, what it costs, how far it reaches, and whether you can use it at all.
Purpose-built apparatus that uses the behaviour of individual photons to exchange a key between two fixed points. Measuring a quantum state disturbs it, so eavesdropping is physically detectable.
Ordinary software on ordinary computers, built on lattice problems believed to stay hard even for a quantum computer. No special hardware of any kind. This is how almin™ Seal is built.
Asking “is QKD better than PQC” is like asking whether a bank vault is better than a padlock. It depends on what you protect, and how it needs to travel.
QKD encodes information onto individual photons sent down a fibre link. Its security doesn't come from being hard to compute; it comes from quantum mechanics itself: measuring a quantum state disturbs it. Read the photons in transit, and you leave a trace. Watch it happen:
A precisely calibrated single-photon source and detector. Off-the-shelf laptops cannot participate.
Purpose-built optical fibre, or line-of-sight free-space and satellite links. There is no “just connect over the internet.”
Signal loss caps practical range at a few hundred kilometres, then each trusted repeater must itself be physically secured.
QKD establishes a shared secret; it encrypts nothing by itself. AES still does the actual work.
For two fixed, high-value sites such as two data centres or two government facilities, with the budget for dedicated hardware, QKD remains by some measures the gold standard. It was never designed for anything else.
“QKD protects a link. Most people need to protect a file. Those are not the same problem.”
Every file is sealed under two independent, unrelated key agreements running side by side. An attacker must break both the lattice problem behind ML-KEM and the elliptic curve behind X25519 to recover a single file's key. A flaw in either one alone, even in the newer lattice mathematics, is not enough.
A file sealed today stays unreadable once quantum computers exist, because the lattice half of the key agreement is not known to fall to one.
Nothing is uploaded. Creating a key also downloads a working copy of the app itself, so a sealed file stays readable whatever happens to the website.
The private key never leaves the device and is never seen by any server. There is no “forgot passphrase” path, by design rather than oversight.
No independent professional security audit yet. JavaScript can't guarantee constant-time execution. A weak passphrase is still a weak passphrase.
ML-KEM, Argon2id and Blake2b were written from their published specifications and checked against independent reference implementations, with Argon2id checked against the official RFC 9106 test vector.
“Quantum-resistant” does not mean quantum hardware. Seal uses no quantum phenomena at all, only mathematics believed to be hard even for a quantum computer.
Visit almin.co.uk/seal in any modern browser. Nothing to install.
ML-KEM-768 is the sensible default; ML-KEM-1024 for the highest level. Set a passphrase. Four or more random words is a solid floor, and Argon2id is applied automatically.
Your public key, your private key, and a working copy of almin™ Seal itself, named to the version that made it.
Choose the recipient's public key (or your own), drop in any file, and download the resulting .pqf container.
Open the matching private key with its passphrase, drop in the .pqf file, and the original is restored under its original name.
Neither approach is the universally “right” answer. QKD remains the strongest guarantee for two fixed, high-value points. almin™ Seal exists for everyone else, which is almost everyone: anyone who needs to protect a file, sent to an arbitrary recipient, using the computer they already own, starting today.