A master public key (also known as a parent address or extended public key) is a register that groups all your public addresses created on a blockchain. With it, Waltio can automatically import all your addresses without you having to add them one by one.

A master public address/key is a parent address which you can use to find all your public addresses created on a blockchain: the child addresses, and all the read-only data (e.g. associated transactions) of these child addresses.

Step 1: You create a Bitcoin address on your Ledger. You therefore have a public key and a private key linked to your wallet.

The parent address is created (it is also called the master public key, master public address or extended public key).

Step 2: You decide to create another Bitcoin public address on your Ledger in order to have "two accounts". It is thanks to the parent address that Ledger Live generated the second public address, and that it will generate the next public addresses.

Generally speaking, the new address is created when you receive funds in your account.

The parent address is only accessible to you. It is the only link between the two public addresses you have created.

Having the parent address allows you to find all the child addresses, but not vice versa. For example, giving a parent address to a third party enables them to read transactions made on all child addresses.

This is very useful for using a tool like Waltio, which needs to read all your transactions on all your addresses, without having to add your addresses one by one. Even if the purpose is the same, the time saved can be substantial for you.

For example: XPub are master keys of the Bitcoin blockchain whose characteristic is to start with "xpub". We support these keys if they come from a Ledger, Exodus or Trezor wallet.

We have written tutorials to help you add your master key to Waltio depending on your wallet: