When you view your Bitcoin account’s extended public key, you may see prefixes such as xpub, ypub, or zpub.

These prefixes do not represent different keys. They are simply different formats of the same underlying extended public key.

The prefix tells wallet software which Bitcoin address type should be generated from that key.

If you need help locating your extended public key, see our guide:
How to find your extended public key in the BitBoxApp

An extended public key provides read-only access to a Bitcoin account.

Even if someone has your extended public key, they cannot spend or move your bitcoin.
Your private keys remain securely stored inside your BitBox02 and are never exposed.

 

What is an extended public key?

An extended public key allows software to generate all receiving addresses for a specific Bitcoin account.

Think of it as a view-only master key for that account.

With an extended public key, an application can:

  • Generate all receiving addresses for that account
  • View all past transactions
  • Track the account balance

However, it cannot be used to spend funds.


Why do different extended public key formats exist?

Bitcoin has evolved over time and introduced several address types.

Because of this, wallet software must know which address format should be generated.

Extended public key prefixes provide this information.

Recovery Phrase (Seed)

      │
      ├── BIP44  → Legacy
      │           xpub
      │           Address starts with: 1
      │
      ├── BIP49  → Wrapped SegWit
      │           ypub
      │           Address starts with: 3
      │
      ├── BIP84  → Native SegWit
      │           zpub
      │           Address starts with: bc1q
      │
      └── BIP86  → Taproot
                  Address starts with: bc1p

Common extended public key formats

xpub (Legacy)

Legacy addresses are the original Bitcoin address format.

Addresses generated from an xpub begin with:

1

Example address:

17P5g13DGVxmEiPu5PMBjfBkadXkj6gvh5

Characteristics:

  • Oldest Bitcoin address format
  • Widely compatible with older services
  • Highest transaction fees compared to newer formats

ypub (Wrapped SegWit)

Wrapped SegWit was introduced to improve transaction efficiency while maintaining compatibility with older wallets.

Addresses generated from a ypub begin with:

3

Example address:

33HkB9NLhaDWeZL3YkWLzUzBW74prnXy3h

Characteristics:

  • Lower fees than legacy addresses
  • Supported by many services
  • Transitional format between Legacy and Native SegWit

zpub (Native SegWit)

Native SegWit is the modern standard for Bitcoin addresses.

Addresses generated from a zpub begin with:

bc1q

Example address:

bc1qgh7uucu9lsj2awued6h3egazer80mgg7crw7h8

Characteristics:

  • Lowest transaction fees
  • Modern address format
  • Default address type in the BitBoxApp
 
 
Format Address Prefix Standard Typical Derivation Path Status
xpub 1 Legacy (BIP44) m/44'/0'/0' Old
ypub 3 Wrapped SegWit (BIP49) m/49'/0'/0' Transitional
zpub bc1q Native SegWit (BIP84) m/84'/0'/0' Recommended
Taproot bc1p Taproot (BIP86) m/86'/0'/0' Newest

The BitBoxApp uses Native SegWit (zpub) by default because it offers the lowest fees and best efficiency.

 

The special case: Taproot

Taproot is the newest major upgrade to Bitcoin.

Taproot addresses begin with:

bc1p

Example:

bc1p0kdy8ggsuw9a5fykwn3pw2zakwuv0kz67l289ecsj6zayqqv87aqejjam0

While the BitBox02 fully supports Taproot, the BitBoxApp does not display the Taproot extended public key directly.


Taproot compatibility across wallet software

Taproot support is still evolving across the Bitcoin ecosystem.

While Taproot addresses are widely supported, the extended public key format for Taproot accounts is not yet standardized across all wallet software.

Because of this:

  • Some wallets export Taproot accounts using output descriptors
  • Others derive addresses directly from the BIP86 derivation path
  • Some older wallets do not support Taproot at all

For this reason, the BitBoxApp currently does not display a Taproot extended public key directly.

Exporting Taproot account information improperly may cause privacy issues or compatibility problems with certain wallet software.

This feature is therefore intentionally hidden in the BitBoxApp.

Example of viewing Taproot account information in the BitBoxApp.

 

How extended public keys relate to your recovery phrase

Your recovery phrase is the master seed of your wallet.

From this seed, the BitBox02 can generate:

  • Multiple accounts
  • Multiple extended public keys
  • An unlimited number of receiving addresses

Each account in your BitBoxApp has its own extended public key.

Recovery Phrase (Seed)
 └── Bitcoin Account 1 → Extended Public Key
      └── Many receiving addresses

 └── Bitcoin Account 2 → Extended Public Key
      └── Many receiving addresses
 

Privacy considerations

Sharing your extended public key allows a service to see all transactions and balances for that account.

This means they can track:

  • Past transactions
  • Current balance
  • Future incoming payments

Never share your extended public key with services you do not trust.

Anyone with this key can monitor your entire transaction history for that account.

 

When would you use an extended public key?

Most users never need to use their extended public key manually.

However, it can be useful for:

  • Creating a watch-only wallet on another device
  • Importing transactions into tax or accounting software
  • Connecting portfolio tracking services
  • Integrating with compatible third-party wallet software

FAQ

Can someone steal my bitcoin if they have my extended public key?

No.

An extended public key only provides view-only access to an account.
It cannot be used to spend funds or move bitcoin.

Your private keys remain securely stored on your BitBox02.


Is an extended public key a backup?

No.

Your recovery phrase is your only backup.

If you lose your device, you recover your wallet using your recovery phrase — not your extended public key.


Why should I not reuse Bitcoin addresses?

Reusing addresses allows outside observers to link multiple transactions together, which reduces your financial privacy.

Wallets like the BitBoxApp automatically generate new addresses to prevent this.


Is a zpub less secure than an xpub?

No.

The underlying cryptographic key is identical.

The prefix (xpub, ypub, zpub) only indicates which address type the wallet should generate.


If I convert a zpub to a ypub, does it change my key?

No.

Converting between formats does not change the underlying key.

It only changes the format label used by wallet software.


Does my recovery phrase contain only one extended public key?

No.

Your recovery phrase generates many extended public keys.

Each account in your wallet has its own extended public key.


What is an output descriptor?

An output descriptor is a modern way to describe how a wallet generates addresses.

It contains more complete information than a single extended public key and is becoming the preferred standard for advanced wallet setups.


Can I import my BitBox extended public key into another wallet?

Yes.

You can import an extended public key into compatible wallets such as Sparrow or Electrum to create a watch-only wallet.

This allows you to monitor transactions without connecting your BitBox02.