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Blockchain Luxembourg Ltd.
Trading nameBlockchain
FoundedAugust 30, 2011[1]
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:Not to be confused with the block chain. (TOR onion site) is a utility site offering a number of free ad-supported services:

  • Alternative block chain browser
  • Javascript-based eWallet
  • Payment notification/alerts
  • Live updating list of unconfirmed transactions
  • Data and charts providing insight into the Bitcoin P2P network
  • Double spend tracking
  • JSON and block explorer compatible api
  • Multi-signature coordination service (for use with M-Of-N transactions)
  • Mixing Service

The site's availability status and service history is monitored using PingDom.

The site was launched on August 30, 2011, originally as the PiUK-BlockChain-Browser. It was built with the intended purpose of recording double spend attacks and various currency statistics.

On March 26, 2012 the Blockchain for Android mobile app was released[2]. On April 20, 2012 the Blockchain ios app for the Apple iPhone, iPod touch and iPad was released globally on the App Store[3].


The wallet available from this service is considered a hybrid EWallet. This means that the coins are not stored with, but instead held in your browser. There is an encrypted copy of your wallet stored on's server, but that does not have your wallet password and thus cannot access or spend from your wallet.

The same wallet is accessed using the Blockchain for Android mobile wallet.

To access the wallet, the wallet identifier needs to be known or bookmarked. To allow for the wallet to be accessed using an easily-remembered word or term, the service allows you to enter an alias to the wallet identifier.


Access to the wallet requires a password. After multiple successive failed attempts to login (e.g., five) the account will be locked for a period of four hours[4].

Mutli-factor authentication is available to further protect access to the wallet. This authentication is valid for the session for a limited amount of time[5]. These methods include:

  • Google Authenticator
  • e-mail verification
  • SMS
  • YubiKey


Though the service does store an encrypted copy of your wallet, the recommendation is for the wallet owner to also keep a backup copy of the encrypted wallet. Configuring an e-mail address in the account details will then make it possible to manually request that a backup of the wallet be sent by e-mail to that address. There will also be a backup sent if there were any changes to the wallet, such as after importing private keys. If you are backing up by email enable 2 factor authentication on the email account as well. does not ask for their sites' 2FA when importing from backup. A hacker who gained access to your email account can import and empty your wallet if he finds your wallet password. Otherwise this backup is generally secure because the wallet is encrypted though wallet owners holding larger balances may want to obtain advice from a security professional regarding the risks.

Mobile Apps


Users of the Blockchain mobile app may wish to add the second password capability (configured through Account Details -> Security) so that bitcoins cannot be spent without the additional password.

See Also

External Links


  1. BitcoinTalk thread 40264. New block explorer type site needs testing / feedback 2011-08-30.
  2. android wallet
  3. iPhone IOS Bitcoin wallet is here! (From
  4. - Bitcoin Block explorer & Currency Statistics
  5. Authentication somehow remembers me