bitcoin is no size .
I can guarantee that if you've been hitting up faucets and collecting enough Satoshis to add up to one Bitcoin then you would have one very large Bitcoin on the blockchain.
Here is an actual transaction from the blockchain represented in hexadecimal sending 0.099 BTC to 1NScWjpKqfLkAf2q9tMXhansZQRpM5HUS3 and paying a 0.001 BTC fee, for a total of 0.1 BTC spent from the sender's wallet. It is 192 bytes long. I've color coded each piece of data to match up with my color coded descriptions that follow. Each byte is represented with 2 hexadecimal digits, so the string of numbers and letters below is 384 digits:
You can look at the pieces of the transaction and decide for yourself how big you think "a bitcoin" is. The 8 bytes that franky1 was talking about are seen in the description below where I state:
- 8 bytes indicating quantity of satoshis this output supplies to a transaction if it is used as an input in the future (0000000000970fe0)
But you'll also notice that the representation of the 0.01 BTC that is being spent is handled by 36 bytes that refer back to where the output was created, and the new 0.099 BTC output that is created by this transaction doesn't exist unless this entire 192 byte transaction exists.
000000010174c1ca3b4bdb3e58daaf87774a09495ae5316995e37b05d7aab21c
063c72a0b4000000076b483045022100e25ca2d2d56e50df86837a865184a1ef3
af0a0a301f3cfaee4a3db5ac237d62c02202d7f914835ac982b31d176e4ca8eb98b
caffa17a7e40a474084bd1b5e0b2e366012102fb624f78133dae97cf2269a1510f
bfbc0c7e45ce43fc629a7389ec1a7aab4676fffffffe010000000000970fe01976a914
eb32af5e891a586834b1411511a93747d06ad55f88ac00060ef2
(Note: Transactions in hex are typically represented in little-endian byte order. This transaction has been converted to big-endian byte order so that the conversions from hex to decimal won't be as confusing to those that are unfamiliar with the
differences between the two representations.)
- 4 bytes version number (00000001)
- 1 byte indicating quantity of inputs (01)
- 32 byte transaction ID indicating where the 0.1 BTC input that is being spent was originally created as an output (74c1ca3b4bdb3e58daaf87774a09495ae5316995e37b05d7aab21c063c72a0b4)
- 4 byte index indicating which output from that previous transaction is being spent as an input in this transaction (00000007)
- 1 byte indicating the size of the Txin-script (6b)
- First byte of Txin-script indicating size of the data to be pushed onto the stack (48)
- 71 byte DER encoded ECDSA signature (3045022100e25ca2d2d56e50df86837a865184a1ef3af0a0a301f3cfaee4a3db5ac237d62c02202 d7f914835ac982b31d176e4ca8eb98bcaffa17a7e40a474084bd1b5e0b2e366)
- In this case the DER encoded signature consists of:
- 1 byte header indicating a compound structure (30)
- 1 byte indicating the size of the rest of the signature (45)
- 1 byte indicating that the following data represents an integer (02)
- 1 byte indicating the size of the following integer (21)
- 33 byte R coordinate (00e25ca2d2d56e50df86837a865184a1ef3af0a0a301f3cfaee4a3db5ac237d62c)
- 1 byte indicating that the following data represents an integer (02)
- 1 byte indicating the size of the following integer (20)
- 32 byte S coordinate (2d7f914835ac982b31d176e4ca8eb98bcaffa17a7e40a474084bd1b5e0b2e366)
- 1 byte hashtype code, SIGHASH_ALL (01)
- 1 byte indicating the size of the data to be pushed onto the stack (21)
- 33 byte compressed ECDSA public key (02fb624f78133dae97cf2269a1510fbfbc0c7e45ce43fc629a7389ec1a7aab4676)
- 4 byte sequence number (fffffffe)
- 1 byte indicating the quantity of outputs (01)
- 8 bytes indicating quantity of satoshis this output supplies to a transaction if it is used as an input in the future (0000000000970fe0)
- 1 byte indicating the size of the Txout-script (19)
- 25 byte Txout-script (76a914eb32af5e891a586834b1411511a93747d06ad55f88ac)
- In this case the Txout-script data consists of:
- 1 byte Txout-script OP code, OP_DUP (76)
- 1 byte Txout-script OP code, OP_HASH160 (a9)
- 1 byte indicating the size of the public key hash (14)
- 20 byte public key hash (eb32af5e891a586834b1411511a93747d06ad55f)
- 1 byte Txout-script OP code, OP_EQUALVERIFY (88)
- 1 byte Txout-script OP code, OP_CHECKSIG (ac)
- 4 byte locktime (00060ef2)