Multi Signature Hardened Online Bitcoin Wallet

You're three steps away from a free secure modern Bitcoin wallet

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Features

We secure your coins using 2 private keys you control.

Splitting keys in this way adds a whole new level of security for your Bitcoins.

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Multi Signature

We split our keys between your smartphone and encrypted on our server.

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Out of Band

Payments require your secure passphrase AND a signature from your phone.

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Keys in your Control

The key held on our server is encrypted with your passphrase in the browser.

Getting Started

It's as simple as 1-2-3

Cryptographically Secure

We use the current best in class encryption and multi signature Bitcoin technology to secure your wealth.

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How does CarbonWallet compare to other Bitcoin wallets?

Features

Carbon Wallet

Coinbase/Circle

Blockchain.info

Multi Signature Transaction Support

Allows keys to spread across devices for maximum security

BIT ID Authentification

Use your smartphone to access your wallet and avoid keyloggers and other malware.

HD Wallet

Easy wallet backups just by writing down a passphrase.

Operator has access to funds

If the wallet operator is hacked will you lose your coins?

No Access
Full Access
Partial Access

Out of Band 2 Factor

Out of band 2 factor authentication means your 2 factor security is not open to social engineering.

Technical Details

A more detailed breakdown for the more technically inclined.

We operate a 2 of 2 multi signature wallet. When you pair your smartphone with CarbonWallet you send us an extended public key. We never see the private key on your phone.

The second private key is generated in the browser (similar to blockchain.info/wallet) and encrypted in the browser with your passphrase.

We then combine the 2 extended public keys to create the 2 of 2 wallet.

Carbon wallet can create a Bitcoin transaction with the 2 extended public keys but can't sign it.

The first signature is generated with javascript in the browser when you enter your passphrase to decrypt the BIP38 encrypted private key.

The second signature is supplied by your smartphone. You have to scan a QR code which gives the phone the information required to retrieve the transaction form our servers. The smartphone signs the transaction and sends it back to CarbonWallet.

When we receive the fully signed transaction we broadcast it to the Bitcoin network.

You can download your backup PDF. To retrieve your coins you will need your CarbonWallet password and the BIP39 mnemonic backup of your CarbonKey.