How to view xpub from my Jade

[jeanluca]

Correct me if I'm wrong, but the only way to view the xpub of my Jade is with a QR. Is there a way to view the xpub somewhere  and not in a software wallet? The thing is, that when I scan my xpub in, for example, Sparrow wallet, it will show me a fingerprint an xpub. But how do I know that what I see is correct? I have no way to verify this outside my software wallet

Also, when you register a multi sig wallet in your Jade, you'll also see xpubs and fingerprints per seed. But how do I know if they're correct?

[franky1]

so many jade related questions recently... its as if a big company like blockstream got hundreds of millions of dollars from investors... rushed a product, but couldnt be bothered to have their own support team.. support forum/support ticket system

advice: go speak to blockstream and ask them for a userguide and FAQ of common issues

[Charles-Tim]

@franky1
This has been the reason I decided not to answer this question. Also I see this as someone being bothered to much. The xpub will generate the same addresses and which can be verified.

https://help.blockstream.com/hc/en-us/articles/20270907312665-Verify-receive-addresses-with-Jade-air-gapped#:~:text=Verify%20a%20Receive%20Address,you'd%20like%20to%20verify.

Blockstream have almost all the answers of the question asked online. Also on each guide, you can click on contact support. I have not clicked on it before to know if it is only a bot or not.

[Pmalek]

Correct me if I'm wrong, but the only way to view the xpub of my Jade is with a QR. Is there a way to view the xpub somewhere  and not in a software wallet?

I think you are right. If I remember the installation process properly, Jade only displays the QR code and not the xPUB itself. You can only switch between single and multisig and script types. 

The thing is, that when I scan my xpub in, for example, Sparrow wallet, it will show me a fingerprint an xpub. But how do I know that what I see is correct?

Verify that each address you intend to deposit to is part of your Jade wallet. Load the QRseed into your Jade, scan the QR of the deposit address from your Sparrow wallet with Jade and the HW will tell you if the address is part of your wallet. If you scanned an address that isn't derived from your Jade seed or you imported a wrong xPUB, the Jade wouldn't be able to verify the receiving address you scanned from Sparrow.

[satscraper]

Correct me if I'm wrong, but the only way to view the xpub of my Jade is with a QR. Is there a way to view the xpub somewhere  and not in a software wallet? The thing is, that when I scan my xpub in, for example, Sparrow wallet, it will show me a fingerprint an xpub. But how do I know that what I see is correct? I have no way to verify this outside my software wallet

Also, when you register a multi sig wallet in your Jade, you'll also see xpubs and fingerprints per seed. But how do I know if they're correct?

AFAIK, ^{contrary to Passport 2} Jade doesn't reveal xpub's fingerprint on its display ^{Passport 2 does!} thus the one  way to see it is to use 3^rd party software ^{like Sparrow}.

You may also see for yourself the correctness of Sparrow ^{(in respect of displaying that fingeprint)}  via stand-alone iancoleman  BIP 39 generator.

1) Launch it on the cold air gapped machine.

2) Input your Jade Seed into  "BIP39 Mnemonic" field.

3) Select the correct derivation path

4) Look at "BIP32 Extended Public Key" and copy somewhere the record of this field.

5) Find  SHA256 digest of this record and after this the RIPEMD160 digest of that SHA256 hash. ^{May do it even online as SEED can not be determined from xpub}.

6) Take first four bites of  RIPEMD160[SHA256]. According to BIP32 the result you get will represent the fingeprint of relevant xpub.

[jeanluca]

Correct me if I'm wrong, but the only way to view the xpub of my Jade is with a QR. Is there a way to view the xpub somewhere  and not in a software wallet? The thing is, that when I scan my xpub in, for example, Sparrow wallet, it will show me a fingerprint an xpub. But how do I know that what I see is correct? I have no way to verify this outside my software wallet

Also, when you register a multi sig wallet in your Jade, you'll also see xpubs and fingerprints per seed. But how do I know if they're correct?

AFAIK, ^{contrary to Passport 2} Jade doesn't reveal xpub's fingerprint on its display ^{Passport 2 does!} thus the one  way to see it is to use 3^rd party software ^{like Sparrow}.

You may also see for yourself the correctness of Sparrow ^{(in respect of displaying that fingeprint)}  via stand-alone iancoleman  BIP 39 generator.

1) Launch it on the cold air gapped machine.

2) Input your Jade Seed into  "BIP39 Mnemonic" field.

3) Select the correct derivation path

4) Look at "BIP32 Extended Public Key" and copy somewhere the record of this field.

5) Find  SHA256 digest of this record and after this the RIPEMD160 digest of that SHA256 hash. ^{May do it even online as SEED can not be determined from xpub}.

6) Take first four bites of  RIPEMD160[SHA256]. According to BIP32 the result you get will represent the fingeprint of relevant xpub.

How important is the finger print? I tried to compute the fingerprint, but mine was not the same as the one sparrow shows. Probably due to the fact that it show the Master Fingerprint.

[satscraper]

How important is the finger print? I tried to compute the fingerprint, but mine was not the same as the one sparrow shows. Probably due to the fact that it show the Master Fingerprint.

For me the fingeprint is very important because it depends on both SEED and extension ^{i.e. passphrase}  to SEED. In Passport 2 I need to input my  passphrase ^{contrary to SEED which is stored by my device} every time after correct PIN and if I make the errors the shown  fingerprints are different from that one which I expect. If this happens I just repeat the password imputing. Thus it saves my nerves.

[nc50lc]

-snip-

How important is the finger print? I tried to compute the fingerprint, but mine was not the same as the one sparrow shows. Probably due to the fact that it show the Master Fingerprint.

It's not too important when it comes with the watch-only wallet's functions since it can derive public keys and create unsigned transactions without it.
But it's a requirement of most wallets to verify that you're using the correct signer, so those will not sign a transaction unless it matches.

It's computed from the master private key itself.
Here's how to actually compute it: /index.php?topic=5444628.msg61903879#msg61903879
It has to be the "m" ("BIP32 Root Key" in IanColeman's tool) not any other child xprv derived from it.
And you need another tool to separate the "private key" from the "chain code" of your master private key (xprv),
The tool should base58 decode the xprv, remove the last 4-Byte checksum, the private key should be the 32 Bytes prior to those checksum bytes, then calculate its compressed public key pair.

[Pmalek]

AFAIK, ^{contrary to Passport 2} Jade doesn't reveal xpub's fingerprint on its display ^{Passport 2 does!} thus the one  way to see it is to use 3^rd party software ^{like Sparrow}.

The Jade shows the wallet's fingerprint on its display. It has to be in an "Active" status for it to be displayed. For stateless use, that means you will have to load your seed from a QR and enter the correct passphrase (if you created one). After that, the 8-character fingerprint appears on the bottom right of your Jade's display.

[satscraper]

The Jade shows the wallet's fingerprint on its display. It has to be in an "Active" status for it to be displayed. For stateless use, that means you will have to load your seed from a QR and enter the correct passphrase (if you created one). After that, the 8-character fingerprint appears on the bottom right of your Jade's display.

Good to hear this ^{as I don't have Jade}. Then, it should be no problem for OP to check whether Sparrow ^{paired with Jade} exposes this fingerprint   correctly ^{(I'm sure it does it right,  as it would be hard to assume opposite for  established wallet which I credit the most)}.

[jeanluca]

Thanks a lot for helping. I completely  overlooked that code in the bottom right.