<p>Got it: the last byte 01 stands for compression and has to be dropped</p>

CC BY-SA 3.0
2018-03-06T13:51:14.307Z
cool, you found it - here was last recently a discussion on it: https://bitcoin.stackexchange.com/questions/69315/how-are-compressed-pubkeys-generated/69322?noredirect=1#comment80498_69322
pebwindkraft
CC BY-SA 3.0
2018-03-06T12:22:18.547Z
2018-03-06T12:22:18.547Z
Karan
<p>I have read that private key is 256 bits or 32 byte. <a href="https://en.bitcoinwiki.org/wiki/Private_key" rel="nofollow noreferrer">see here</a></p>

<p>I generated a key on bitcoin-test network. </p>

<p>WIF:</p>

<blockquote>
  <p>cVe4tA6QHduboeSiQD6Y6nzV1QjaVpDVG2YHbqbtJiSCxsNDYYUF</p>
</blockquote>

<p>HEX:</p>

<blockquote>
  <p>f06e4a9c228dafff48e6a44eb9527a14374a203a5750de01c0cf39e7280ce45501</p>
</blockquote>

<p>if you notice above hex is 33 bytes!</p>

<p>I went  on to sign a transaction :</p>

<blockquote>
  <p>01000000015760c907060ca47bbf97a964a435387c38fd86c307e920c1d29ce1a3d0d4d56b010000001976a914ca560954433f0fd1bda9bb566607d1724559b0db88acffffffff02d0070000000000001976a914f9ad22432bb6eb5e4262f9e4bcfb09fda2f5167b88ace068be07000000001976a914ca560954433f0fd1bda9bb566607d1724559b0db88ac0000000001000000</p>
</blockquote>

<p>generated the following tx hash:</p>

<blockquote>
  <p>01000000015760c907060ca47bbf97a964a435387c38fd86c307e920c1d29ce1a3d0d4d56b010000006b483045022100f2224f424a63675682f062fbf6699028727e13d26dc382af6dca57dfb21e9910022011b485e63f8f0045c40f8df41bcab13040bc554da4c176a380c81d18c615b210012103b9dc990c2b8a999ba68bf80cbff94fd85d62a01c7dc48252156f78c813b0aa67ffffffff02d0070000000000001976a914f9ad22432bb6eb5e4262f9e4bcfb09fda2f5167b88ace068be07000000001976a914ca560954433f0fd1bda9bb566607d1724559b0db88ac00000000</p>
</blockquote>

<p>and when i broadcasted it got <a href="https://live.blockcypher.com/btc-testnet/address/n4H7xNPyAkUwc6MELoAHT47V8z69ektmcd/" rel="nofollow noreferrer">accepted</a>!</p>

<p>Now my question is, how can 33 byte private key be valid signing key?</p>

<p>P.S. please don't take out the coins, they are worthless and i need for testing. thanks!</p>

<transactions><private-key><signature>
33 byte private key?
Karan
# 33 byte private key?

(Asked by: username_0 on 2018-03-06)

I have read that private key is 256 bits or 32 byte. [see here](https://en.bitcoinwiki.org/wiki/Private_key)

I generated a key on bitcoin-test network.

WIF:

> cVe4tA6QHduboeSiQD6Y6nzV1QjaVpDVG2YHbqbtJiSCxsNDYYUF

HEX:

> f06e4a9c228dafff48e6a44eb9527a14374a203a5750de01c0cf39e7280ce45501

if you notice above hex is 33 bytes!

I went on to sign a transaction :

> 01000000015760c907060ca47bbf97a964a435387c38fd86c307e920c1d29ce1a3d0d4d56b010000001976a914ca560954433f0fd1bda9bb566607d1724559b0db88acffffffff02d0070000000000001976a914f9ad22432bb6eb5e4262f9e4bcfb09fda2f5167b88ace068be07000000001976a914ca560954433f0fd1bda9bb566607d1724559b0db88ac0000000001000000

generated the following tx hash:

> 01000000015760c907060ca47bbf97a964a435387c38fd86c307e920c1d29ce1a3d0d4d56b010000006b483045022100f2224f424a63675682f062fbf6699028727e13d26dc382af6dca57dfb21e9910022011b485e63f8f0045c40f8df41bcab13040bc554da4c176a380c81d18c615b210012103b9dc990c2b8a999ba68bf80cbff94fd85d62a01c7dc48252156f78c813b0aa67ffffffff02d0070000000000001976a914f9ad22432bb6eb5e4262f9e4bcfb09fda2f5167b88ace068be07000000001976a914ca560954433f0fd1bda9bb566607d1724559b0db88ac00000000

and when i broadcasted it got [accepted](https://live.blockcypher.com/btc-testnet/address/n4H7xNPyAkUwc6MELoAHT47V8z69ektmcd/)!

Now my question is, how can 33 byte private key be valid signing key?

P.S. please don't take out the coins, they are worthless and i need for testing. thanks!

**Tags:** transactions, private-key, signature


---

## 1 answers

### Answer by username_0 on 2018-03-06. Score: 4

Got it: the last byte 01 stands for compression and has to be dropped

> **Comments:**
> **username_1**: cool, you found it - here was last recently a discussion on it: https://bitcoin.stackexchange.com/questions/69315/how-are-compressed-pubkeys-generated/69322?noredirect=1#comment80498_69322  

---

