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xPub – where can I find the xPub key from my wallet?
What is an xPub Key?
To receive Bitcoin payments, a separate and unique Bitcoin address must be created for each payment. This Bitcoin address is a public address, as this address can be communicated to anyone. In order for this infinite number of public Bitcoin addresses to be created automatically, an Extended Public Address, or xPub for short, is required.
Every Bitcoin payment made to a Bitcoin address generated from the xPub key will be credited to your own Bitcoin wallet.
The xPub Key is like a main account at a bank where you can generate an infinite number of sub-accounts, each with a unique IBAN number. This means that a new, separate IBAN number can be used for each deposit. Each incoming payment can be clearly assigned and does not require any further details such as a reason for payment.
There are Bitcoin wallets from which you can extract your xPub key. Then the xPub key can be deposited with the BTCPay server and used for payment processing.
The Bitcoin payment receipts are then credited directly to the associated Bitcoin wallet.
We would like to point out that when sharing the public key (xPub), the entire transaction history can be viewed. The transactions can only be viewed, but no dispositions can be made.
The private key is required in order to make dispositions. This private key is often represented in the form of 24 words and must never be passed on. Whoever knows this private key also owns the Bitcoin.
If you run your own BTCPay server, then you can use the internal Bitcoin wallet and using an external xPub key is not mandatory.
If you use a BTCPay server, it is recommended that you store your own xPub key.
In order to be able to deposit the xPub key with the BTCPay server, you can find out here which Bitcoin wallet can extract the xPub key and where you can find the xPub key.
There are different key standards. We recommend using the BIP49 standard for SegWit P2WPKH P2SH addresses.
With Segwit, payers benefit from low transaction fees. If we were to use Segwit alone, the bitcoin addresses would start with bc1.
However, there are still some end-user wallets that do not fully support Segwit. In order not to exclude these customers, we recommend the use of segwit p2sh. This bitcoin address start with the 3.
What is a GAP Limit?
With the help of the xPub Key, 20 Bitcoin addresses are created in advance. These Bitcoin addresses are used by the BTCPay server to display them to customers in the payment page. In parallel, the blockchain is constantly checked to see whether a payment has been received at one of these 20 Bitcoin addresses.
Each time the payment page is accessed, a new Bitcoin address is used. If no payment is made for any of the 20 calls, the so-called GAP limit is reached.
When using an xPub key for the BTCPay server, we recommend an external wallet where the GAP limit can be increased.
This is possible with the Electrum Wallet and the Bitbox Wallet.
Where can I find my xPub Key?
In this article we will show you how to use the xPub key on hardware wallets:
find.
Then there are instructions for the Blockchain.com web wallet and for the Electrumwallet, and with a Raspiblitzwe have created separate instructions. You can find them under:

Bitbox
Um auf den erweiterten öffentlichen Schlüssel (xPub) bei der Bitbox zuzugreifen, klickst Du auf die Schaltfläche “Account Info” in der oberen rechten Ecke.


You will then see all the extended public keys associated with that account.
The xPub Key is displayed in the form of a QR code and below it as a plain text key.
GAP Limit
The default GAP limit is 20 addresses. With Bitbox you can increase this limit.
Mac and Linux users open Terminal for this purpose.
Enter the command: cd Applications and change to the Application directory.
Then, if the limit is to be increased to 100 addresses, the command is:
open -a BitBox.app – -args -gapLimitReceive 100 -gapLimitChange 100
For more information on the GAP Limit at Bitbox, see: https://shiftcrypto.support/help/en-us/15-other/34-how-can-i-change-the-bitboxapp-gap-limits
Buy a bitbox now: https://shiftcrypto.shop/en/
Ledger

Quelle: https://support.ledger.com/hc/en-us/articles/360011069619-Extended-public-key
To get the xPub key, click on the icon with the wrench.
You get the account information displayed and switch to Advanced Logs and the Edit Account field is displayed.
There you will find a string that starts with xpub and you copy it out.
Buy a Ledger now: https://shop.ledger.com/
Trezor
Um den xPub Key von Deiner Trezor Wallet angezeigt zu bekommen, steckst Du Deinen Trezor an den Computer und öffnest die Webseite wallet.trezor.io
Then click on the name of your device and switch to the tab labeled Basic.
Then you let Show xPub display the xPub key as QR code or as text key.

Buy a Trezor now: https://shop.trezor.io/
Blockchain.com

Bei der Bitcoin Wallet von Blockchain.com handelt es sich um eine Internet-Wallet. You open an account with the provider Blockchain.com and go to the Settings section and then to Wallet & Addresses.
Dann siehst Du den Bereich Manage und klickst da drauf.


Then the selection window pops up and you choose Show xPub.
Dann bekommst Du den xPub Key für diese eine Wallet entsprechend dargestellt:
Now copy the xPub key from the gray field and paste it into the BTCPay store.
Electrum Wallet
Bei der Electrum Wallet handelt es sich um ein Bitcoin Wallet, welche Du auf Deinem eigenen Computer installieren und einrichten kannst.
You can find a detailed guide to Electrum Wallet here: Create xPub Key with the Electrum Wallet
Raspiblitz
The Raspiblitz is a hardware node that can be used to receive Bitcoin (OnChain) and Lightning (Off-Chain) payments.
There is also a dedicated BTCPay server on the Raspiblitz. If you operate your Raspiblitz in your own network, it may be undesirable for security reasons that an uncontrolled access from the Internet is possible.
However, access would be required if end customers want to pay with Bitcoin in their own online store and this payment processing is to be carried out via the BTCPay server.
Therefore, it is recommended that an external BTCPay server is used for Bitcoin payment processing and not the BTCPay server on your own Raspiblitz in your own network.
The crediting of Bitcoin and Lightning payments, on the other hand, is to take place directly on the company’s own Raspiblitz.
You can find detailed instructions for Electrum Wallet here: xPub Key Raspiblitz
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