<p>To mine the testnet genesis block you would use.</p>

<pre><code>python genesis.py -z "The Times 03/Jan/2009 Chancellor on brink of second bailout for banks" -n 414098458 -t 1296688602
</code></pre>

<p>If you want to create a new genesis block run the following with your own time and leave out the nonce, you will be generated a new nonce.</p>

<pre><code>python genesis.py -z "The Times 03/Jan/2009 Chancellor on brink of second bailout for banks" -t 1501755824
</code></pre>

<p>Here is what I get when running the above command, it will just take some time to find a block.</p>

<pre><code>python genesis.py -z "The Times 03/Jan/2009 Chancellor on brink of second bailout for banks" -t 1501755824
04ffff001d0104455468652054696d65732030332f4a616e2f32303039204368616e63656c6c6f72206f6e206272696e6b206f66207365636f6e64206261696c6f757420666f722062616e6b73
algorithm: SHA256
merkle hash: 4a5e1e4baab89f3a32518a88c31bc87f618f76673e2cc77ab2127b7afdeda33b
pszTimestamp: The Times 03/Jan/2009 Chancellor on brink of second bailout for banks
pubkey: 04678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0ea1f61deb649f6bc3f4cef38c4f35504e51ec112de5c384df7ba0b8d578a4c702b6bf11d5f
time: 1501755824
bits: 0x1d00ffff
Searching for genesis hash..
183984.0 hash/s, estimate: 6.5 h
nonce: 835054047
genesis hash: 00000000ad3d3d6aa486313522fdd4328509feefe8c37ead2a609884c6cbab92
</code></pre>

<p>To add your new genesis block to the Bitcoin testnet update the src/chainparams.cpp file, also delete any checkpointData entries on the testnet as those no longer apply to your new testnet chain.</p>

CC BY-SA 3.0
2017-11-14T08:33:40.800Z
This code crashes often when mining a genesis block that isn't the original bitcoin genesis block :(
Barney Chambers
CC BY-SA 3.0
2017-11-16T15:18:39.977Z
What are you typing in exactly? If you paste it here I can help, I use GenesisH0 often to add RegTest and TestNet genesis blocks to coins that do not have them and once in a while a new MainNet block.
Peter Bushnell
CC BY-SA 3.0
2017-08-03T10:29:39.933Z
2017-08-03T13:02:38.217Z
2017-08-03T13:02:38.217Z
Peter Bushnell
<p><strong>Bitcoin 0.14</strong>
I want to try mining first genesis block, a new time, but don't know how to start
<strong>testnet</strong></p>

<p>used to create GenesisH0
<a href="https://github.com/lhartikk/GenesisH0" rel="nofollow noreferrer">https://github.com/lhartikk/GenesisH0</a></p>

CC BY-SA 3.0
2017-03-13T10:38:23.540Z
You need to change some code assertion values for your bitcoin testnet.  the peershares wiki should give you a good place to start so you can see what you need to look for in the code for generating a genesis block. https://github.com/Peershares/Peershares/wiki/Genesis-Block-(Starting-a-New-Blockchain-Instance)
Fuzzybear
CC BY-SA 3.0
2017-03-13T11:02:15.717Z
The old descriptions, it is out of date already
menfix
<bitcoin-core><bitcoind><mining-theory>
Mining of the Genesis block testnet?
menfix
# Mining of the Genesis block testnet?

(Asked by: username_0 on 2017-03-13)

**Bitcoin 0.14**
I want to try mining first genesis block, a new time, but don't know how to start
**testnet**

used to create GenesisH0
<https://github.com/lhartikk/GenesisH0>

**Tags:** bitcoin-core, bitcoind, mining-theory

> **Comments:**
> **username_1**: You need to change some code assertion values for your bitcoin testnet.  the peershares wiki should give you a good place to start so you can see what you need to look for in the code for generating a genesis block. https://github.com/Peershares/Peershares/wiki/Genesis-Block-(Starting-a-New-Blockchain-Instance)  
> **username_0**: The old descriptions, it is out of date already  

---

## 1 answers

### Answer by username_2 on 2017-08-03. Score: 1 | Accepted answer

To mine the testnet genesis block you would use.

```
python genesis.py -z "The Times 03/Jan/2009 Chancellor on brink of second bailout for banks" -n 414098458 -t 1296688602

```

If you want to create a new genesis block run the following with your own time and leave out the nonce, you will be generated a new nonce.

```
python genesis.py -z "The Times 03/Jan/2009 Chancellor on brink of second bailout for banks" -t 1501755824

```

Here is what I get when running the above command, it will just take some time to find a block.

```
python genesis.py -z "The Times 03/Jan/2009 Chancellor on brink of second bailout for banks" -t 1501755824
04ffff001d0104455468652054696d65732030332f4a616e2f32303039204368616e63656c6c6f72206f6e206272696e6b206f66207365636f6e64206261696c6f757420666f722062616e6b73
algorithm: SHA256
merkle hash: 4a5e1e4baab89f3a32518a88c31bc87f618f76673e2cc77ab2127b7afdeda33b
pszTimestamp: The Times 03/Jan/2009 Chancellor on brink of second bailout for banks
pubkey: 04678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0ea1f61deb649f6bc3f4cef38c4f35504e51ec112de5c384df7ba0b8d578a4c702b6bf11d5f
time: 1501755824
bits: 0x1d00ffff
Searching for genesis hash..
183984.0 hash/s, estimate: 6.5 h
nonce: 835054047
genesis hash: 00000000ad3d3d6aa486313522fdd4328509feefe8c37ead2a609884c6cbab92

```

To add your new genesis block to the Bitcoin testnet update the src/chainparams.cpp file, also delete any checkpointData entries on the testnet as those no longer apply to your new testnet chain.

> **Comments:**
> **username_3**: This code crashes often when mining a genesis block that isn't the original bitcoin genesis block :(  
> **username_2**: What are you typing in exactly? If you paste it here I can help, I use GenesisH0 often to add RegTest and TestNet genesis blocks to coins that do not have them and once in a while a new MainNet block.  

---

