Smart Contract Creation Cost

The cost to deploy a smart contract on ethereum has six factors. The biggest factors are the contract size and what code gets executed during the deployment phase. We will give a step by step example with a simple contract.

We will translate "gas" into dollars at the end of the article.

Smart contract deployment cost

• The 21,000 gas that all Ethereum transactions must pay
• A fixed cost of 32,000 gas for creating a new contract
• 22,100 gas for each storage variable set
• 4 gas for each zero byte in the transaction data 16 gas for each non-zero byte in the transaction.
• The cost to execute each bytecode during the initialization
• 200 gas per byte of deployed bytecode

Let’s use an example of a deploying a minimal Solidity contract in Remix

pragma solidity 0.8.7;

contract Minimal {
    constructor() payable {

    }
}

Note that the deployment cost according to remix was 66,862. We will break down this cost in this article.

We have made the constructor payable and set the optimizer to 200 runs. This has the effect of making the smart contract smaller.

Let’s add it up

21,000 gas | deployment
32,000 gas | creation
Total: 53,000

We still have 13,862 gas to account for

Transaction bytecode gas cost (tx.data)

The transaction bytecode was

0x
6080604052603f8060116000396000f3fe6080604052600080fdfea2646970667358221220c5cad0aa1e64e2ca6a6cdf28a25255a8ebbf3cdd5ea0b8e4129a3c83c4fbb72a64736f6c63430008070033

Each hex par is a byte, so let’s add spaces to make it more readable.

To split it up like that, we can use the following python code

import itertools

# note that we manually removed the "0x" at the beginning
s = "6080604052603f8060116000396000f3fe6080604052600080fdfea2646970667358221220c5cad0aa1e64e2ca6a6cdf28a25255a8ebbf3cdd5ea0b8e4129a3c83c4fbb72a64736f6c63430008070033"
s = " ".join(["".join(group) for group in itertools.zip_longest(s[::2], s[1::2])])

print(s)

We get

60 80 60 40 52 60 3f 80 60 11 60 00 39 60 00 f3 fe 60 80 60 40 52 60 00 80 fd fe a2 64 69 70 66 73 58 22 12 20 c5 ca d0 aa 1e 64 e2 ca 6a 6c df 28 a2 52 55 a8 eb bf 3c dd 5e a0 b8 e4 12 9a 3c 83 c4 fb b7 2a 64 73 6f 6c 63 43 00 08 07 00 33

Each non-zero byte costs 16 gas, and each zero byte (00) costs 4 gas.

To count them, we can use this python one-liner:

s = "60 80 60 40 52 60 3f 80 60 11 60 00 39 60 00 f3 fe 60 80 60 40 52 60 00 80 fd fe a2 64 69 70 66 73 58 22 12 20 c5 ca d0 aa 1e 64 e2 ca 6a 6c df 28 a2 52 55 a8 eb bf 3c dd 5e a0 b8 e4 12 9a 3c 83 c4 fb b7 2a 64 73 6f 6c 63 43 00 08 07 00 33"

# non-zero bytes
print(len(list(filter(lambda x: x != '00', s.split(' ')))))
# prints 75

# zero bytes
print(len(list(filter(lambda x: x == '00', s.split(' ')))))
# prints 5

We have 75 non-zero bytes and 5 zero bytes. The math works out to 75 x 16 + 5 x 4 = 1220 gas

21,000 gas | deployment
32,000 gas | creation
 1,220 gas | bytecode cost
Total: 54,220 gas. 

We have 12,642 gas to account for to bring the total cost to 66,862.

Deployment code gas cost

Let’s look at the bytecode again

60 80 60 40 52 60 3f 80 60 11 60 00 39 60 00 f3 fe 60 80 60 40 52 60 00 80 fd fe a2 64 69 70 66 73 58 22 12 20 c5 ca d0 aa 1e 64 e2 ca 6a 6c df 28 a2 52 55 a8 eb bf 3c dd 5e a0 b8 e4 12 9a 3c 83 c4 fb b7 2a 64 73 6f 6c 63 43 00 08 07 00 33

The parts in bold are the deployment code. The first part is the initialization code. We need to multiply each of the deployment code by 200 gas to get the cost. This has a higher cost than the bytecode cost above because this is stored in the Ethereum state.

Let’s do that in python again

deployment_code = '60 80 60 40 52 60 00 80 fd fe a2 64 69 70 66 73 58 22 12 20 c5 ca d0 aa 1e 64 e2 ca 6a 6c df 28 a2 52 55 a8 eb bf 3c dd 5e a0 b8 e4 12 9a 3c 83 c4 fb b7 2a 64 73 6f 6c 63 43 00 08 07 00 33'

print(len(deployment_code.split(' ')))
# 63

63 x 200 = 12,600 gas

So here is the breakdown so far

21,000 gas | deployment
32,000 gas | creation
 1,220 gas | bytecode cost
12,600 gas | deployed bytecode
Total: 66,820

Almost there! We are 42 gas short of our 66,862 target.

Bytecode execution gas cost

We also need to factor in the actual execution of the initialization bytecode.

60 80 60 40 52 60 3f 80 60 11 60 00 39 60 00 f3 fe

We can translate that to a more convenient format using the evm playground tool.

PUSH1 0x80 | 3 gas 
PUSH1 0x40 | 3 gas 
MSTORE     | 12 gas 
PUSH1 0x3f | 3 gas 
DUP1       | 3 gas 
PUSH1 0x11 | 3 gas 
PUSH1 0x00 | 3 gas 
CODECOPY   | 9 gas 
PUSH1 0x00 | 3 gas 
RETURN     | 0 gas 
INVALID    | not executed

And the total is 42, as expected. These gas costs were obtained by running the remix debugger.

And we are done, we have accounted for each component of the deployment of a smart contract.

So here is the final breakdown

21,000 gas | deployment
32,000 gas | creation
 1,220 gas | bytecode cost
12,600 gas | deployed bytecode
    42 gas | deployment execution cost
Total: 66,862 gas

Note that if we set storage variables in the constructor, the cost would be higher. We’d have to pay 22,100 gas for each variable set. But to keep this walkthrough manageable, we have omitted that case.

If you want to become a solidity ninja and be able to account for gas costs fluently, sign up for our Solidity coding bootcamp, which is the first blockchain bootcamp in our series of web3 bootcamps. If you want a gentle introduction to gas cost calculation, sign up for our Udemy course.

All the numbers for gas cost obtained here are from the Ethereum Yellow Paper.

Translating smart contract creation cost to dollars

To turn units of "gas" into dollars, the formula is

gas x gas per gwei x price of ether ÷ 1 billion.

Gas per gwei can be obtain from sites like ethgasstation or etherscan. In our example, assuming Eth costs $1,000 and the price of gas is 20 gwei, the cost in dollars would be

66,862 x 20 x 1000 ÷ 1 billion = $1.34

If this seems low, remember, this is a minimal contract with low gas prices. If, like it was in 2021, gas was 100 gwei, the contract deployment cost was 1 million gas, and ether prices was $4,000, then it would come out to $400.