Why do block explorer APIs say the nonce in the block header is 0?



Several block explorers are reporting that the nonce value in many block headers is 0. For example, blockcypher,

Why does this happen?

Where can I get the actual block headers?


Posted 2017-12-29T03:35:24.290

Reputation: 55



This appears to be a bug in their software (i.e. it occurs for no reason other than it's a mistake) so you should report this to Blockcypher.

Andrew Chow

Posted 2017-12-29T03:35:24.290

Reputation: 50 267

Contacted Blockcypher but the same block works fine for them at https://www.blockcypher.com/dev/bitcoin/#blockchain "bits": 419486617, "nonce": 1225187768, but what is modified now is hash (abbreviated) "hash": "0000000000000000189bba3564a63772107b567...", Should I contact Fed Governor Powell under Federal Reserve Bitcoin Strategy and report the case if no remedy by Blockcypher?

– darius – 2017-12-29T05:19:14.647

What are you talking about? Regardless, there is no reason for them to show this other than a bug in their software. Whether they fix it or not is completely up to them. In the meantime, if you need the data that they are incorrectly showing, you should use some other API. – Andrew Chow – 2017-12-29T05:31:52.190

Trust in Bitcoin is based on reliability of Bitcoin data like blocks, block header and more. If we let such sensitive data to be manually modified and manipulated by third parties, trust in Bitcoin may one day get lost, hurting FED and economy the most. If you advise me to hide such foul play from FED I have no experience to make such decision on my own. Do you know any other API for historic block header data download ? – darius – 2017-12-29T05:45:08.233

Trust in Bitcoin has very little to do with the third party data providers. They are not official in any way nor are they supposed to be an authoritative source of data. The data retrieved from them can be validated yourself. If the third party is not trusted, then run a full node yourself and get the data. Full nodes don't use these third parties; they download the blocks directly from other peers and validate them. Furthermore, there are several API providers such as Blocktrail, blockchain.info, chain.so, etc. – Andrew Chow – 2017-12-29T05:50:20.247

https://www.blocktrail.com/api/docs is another Bitcoin service removing "nonce" from hashed blocks: vide example . Description to the left is full. What is returned via API as block example is nonce removed block data.Nonce following difficulty is missing. – darius – 2017-12-29T06:16:13.113

Ok. Complaining about it here isn't going to do you anything. These are bugs in their software, so you should report it to them. – Andrew Chow – 2017-12-29T07:02:04.670

To busy to spend my life on reporting bugs. chain.so is another service hiding nonce variable in the block https://chain.so/api#get-block https://chain.so/api/v2/block/bitcoin/22 API generating error. So this is not a bug but deliberate, clearly stated in API manual. Hope to get historic block headers for download this year. blockchain.info is heavy to extract data values from webpage

– darius – 2017-12-29T07:29:05.320

blockchain.info has an API. You can also download the full blockchain with Bitcoin Core or create a tool which just requests the block headers from nodes on the network. – Andrew Chow – 2017-12-29T07:33:03.557

Your edit to my question's subject line and body make no sense since https://api.blockcypher.com/v1/btc/main/blocks/294327 blockcypher did it alone, modifying historic block header data i.e. setting nonce to "0" as I pointed it out from the very beginning. Others named above just put nothing for nonce line in block header, so your claims are unsupported violating rights of third parties. I screenshot my entries, since otherwise my question gets modified to third party's idea on what I have asked for, making no sense, violating my copyrights since my question is copyrighted as-is.

– darius – 2017-12-29T08:10:35.917

If you disagree with the edit, you can revert it. No copyrights are violated since the copyright is owned by stack exchange. You gave up that right when you registered in this website. Regardless, that is off topic. – Andrew Chow – 2017-12-29T08:25:30.723

Thank you Andrew for your excellent answer and chat. In the meantime I have contacted Chairman Powell about his speech on Blockchain technology, not saying a word about nonce=0 issue https://www.federalreserve.gov/newsevents/speech/powell20170303a.htm# Good luck and Happy New Year.

– darius – 2017-12-29T22:04:19.643