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Split your seed phrase across objects you can hold.

Seedcase turns any seed phrase into separate fragments you store on cards, on paper, on metal. No single fragment reveals anything. No account, no server, no company to trust.

Seedcase desktop app splitting a seed phrase into three fragments

One copy is a single point of failure.

An estimated 3 to 4 million bitcoin will never move again. Almost none of it was hacked. A single copy failed in three ordinary ways.

The copy that was destroyed.

A fire, a flood, a move, a drawer emptied by someone who did not know what the paper was. One accident, and everything is gone at once.

The copy that was stolen.

A burglary, a roommate, a photo that synced to an account you forgot you had. Whoever holds those twelve words holds everything. There is no alarm, and no way to reverse it.

The copy nobody found.

You did everything right, and then you were not there to explain it. Your family knows the assets exist. They will never know where to look, or what to do with a sheet of words if they find it.

Your hardware wallet protects access.
Seedcase protects continuity.

Hardware wallets

Ledger or Trezor protect your seed phrase during transactions. They keep your keys offline and prevent attackers from extracting them. They are excellent at what they do. But they don't solve what happens when the seed itself is lost, destroyed, or unreachable: by accident, by natural disaster, by death.

Seedcase

Not a replacement for your hardware wallet. It's the missing layer that ensures your seed phrase can survive loss, time, and your own absence, without ever giving up non-custodial control. A different problem, and the right tool for it.

How Seedcase works.

Three moves: Split the phrase. Place the fragments. Get the seed phrase back when you need it.

01

Split

Split your seed phrase into as many fragments as you want, and choose how many are needed to put it back together. Two of three, four of seven, seven of ten: you define the rule. No single fragment works alone.

02

Store

Each fragment goes to a different place: a vault, a family home, a notary's office... You choose where each one lives. No single location holds the full secret.

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03

Reconstruct

When you need it, bring together the number of fragments you chose and reconstruct the original seed phrase.

A fragment is an object.

A fragment printed as a QR code on a sheet of paper

Printed sheet

The words printed in full, beside a Seedcase QR. The format a notary can file, a bank can hold, and an heir can read without an app.

A fragment held in the mobile vault on a phone

Mobile vault

A fragment held in the Seedcase encrypted vault app. Sealed at rest, always on you.

A fragment stamped into a stainless steel plate

Metal plate

Fire and water resistant. For the fragment that has to survive the house, not just the decade.

A fragment held in the desktop vault on a laptop

Desktop vault

A fragment held in an encrypted vault on a computer. Sealed at rest.

Seedcase EAL5+ NFC cards in credit-card format

EAL5+ NFC card

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An additional layer of security, on a certified chip. Credit-card format, for a wallet or a safe deposit box.

What people use it for.

Transmission.

Passing on crypto usually means handing someone the seed, or hoping they find it. Seedcase gives you a third way.

  • Fragments go to a family member, a notary, a vault... where none of them can act alone.
  • Together, when the moment comes, they recover everything.
  • No account, no technical knowledge. An object and a written procedure.
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A backup with no single point of failure.

Your seed phrase stops living in one place. Lose a fragment and you still recover everything. Someone finds a fragment and they still have nothing.

Shared control.

Require several people to agree before anything can be put back together. A couple, business partners, a family. Nobody acts alone, and nobody is locked out.

Business continuity.

A company holding crypto on its balance sheet has the same problem, with more people in the room. Several people can recover it together. None of them can do it alone. If one of them leaves, the company still can.

For wealth advisors and notaries

Your clients hold digital assets. Most have no plan for transmitting them, and handing you the seed would make you a custodian.

You can sit in that plan without taking custody. One fragment, below the threshold they set, plus the written procedure. You document it like any other holding. Alone, it opens nothing.

No technical training required. No liability transfer. No custody.

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FAQ

Is my seed phrase compatible with Seedcase?

Yes. Any hardware or software wallet that generates a 12 or 24 word seed phrase in the BIP-39 format is compatible. That is the format almost every wallet uses.

What happens to my fragments if Seedcase disappears?

Nothing. We store no fragments, hold no keys and run no server that your recovery depends on. There is nothing for us to lose, and nothing for us to shut down. Your fragments are SLIP-39 shares in a public format, and our reader is open source.

Do my heirs need Seedcase to recover the wallet?

Not strictly. Your fragments are standard SLIP-39 shares, so any compliant tool can combine them. What that returns is the entropy behind your seed phrase, and converting entropy back into the original words is a standard, documented operation that any BIP-39 tool performs. Seedcase does both steps automatically and in one place.

Is Seedcase custodial?

No. Fragments are generated on your device and stay under your control. We never hold the number of fragments needed to reconstruct anything, and we never hold your seed phrase.

Can someone with one fragment steal my funds?

No. A single share below the threshold reveals no information about your seed phrase. That is a mathematical property of Shamir Secret Sharing, not a policy we enforce.

What happens if I lose a fragment?

Nothing, as long as you still hold the threshold you defined. A 2 of 3 scheme survives the loss of any single fragment. Then reconstruct from what remains, create a new set, and destroy the old fragments you still hold. A lost fragment may still turn up later, in someone else's hands; a new set makes it useless.

What does it cost?

Beta access is free. Pricing beyond the beta is not settled yet, and we would rather announce it once than change it twice.

Has it been audited?

An independent security audit is planned and will be published in full. Until then, the cryptographic core is open source and available for review.

Browse the source on GitHub →

Some things shouldn't depend on luck.