Ethereum is a platform that runs decentralized applications, meaning they don’t need a central server to run. If you’re using Ethereum, you’ll need to know how to find the contract addresses. Once you know how to do it, you’ll enjoy the platform much more.
Here are three ways you can use to find an Ethereum contract address:
- Recalculate the contract address.
- Use Etherscan to see the contract address.
- Call back the address.
You should receive the contract address when you deploy a contract to the Ethereum Blockchain. The address consists of the number of transactions and the creator’s address. If you want to learn more, keep reading!
What Is an Ethereum Contract Address?
Ethereum Blockchains focus on transparency, which is why Etherscan shows all token contracts on this blockchain. You can view the information for free whenever you want.
When searching, you’ll likely have more than one result appear for the contract address.
An Ethereum contract address is a collection of codes and data that stay at an address on the Ethereum blockchain. The contract address runs code enforcing rules – as an ordinary contract would, to which users can submit transactions. It shows the number of transactions sent from the creator.
Essentially, the contract address allows you to understand how many transactions the contract creator has sent.
For those that are new to Ethereum, let’s cover some of the basics below, including what Ethereum is and the different types of Ethereum accounts.
What Is Ethereum?
Many people recently have made the switch to Ethereum. This open-source blockchain makes it simple to share and receive cryptocurrencies. There are some fees associated with using the platform.
Ethereum is a platform that allows you to send and receive cryptocurrency. It works with businesses, finances, and even entertainment. Many people find online currency convenient, with Ethereum being another platform option.
The platform runs on a decentralized network or blockchain, which tracks all ingoing and outgoing tokens. You can think of the blockchain as a ledger, which records all of the finances in it.
If you want to use this platform, you must take some time to learn about Ethereum contract addresses and how to use them efficiently.
Different Types of Ethereum Accounts
There are two different types of Ethereum accounts:
- Externally-owned. Externally accounts belong to anyone who has their keys – the owners have complete control over the account and use it to initiate transactions.
- Smart contract. With a smart contract, the account runs by a program. Smart contracts have a cost associated with them, as they use storage on a network. However, they can process and run transactions automatically.
Both of these accounts have a place on the blockchain, so both use Ethereum contract addresses. To interact with any account, you’ll need to know what address that account has.
Overall, the address is essential for you to make transactions, so it’s best to keep it safe. The good news is that if you do happen to lose it, you don’t need to panic right away.
Finding an Ethereum Contract Address
The Ethereum contract address is where your Ethereum is on the blockchain. Without this number, you cannot interact with the account, meaning you can’t complete transactions with it.
With that in mind, you’ll want to make sure that you go back and retrieve any contract addresses that you might’ve lost.
Let’s look at three ways to do just that.
1. Recalculate the Contract Address
If you’ve lost the contract address, you’re probably really worried. However, keep in mind that this is a common accident among those new to development. You can still reclaim the Ethereum contract by recalculating it.
The platform must deterministically calculate contract addresses. That means you can use a consistent method to determine the address correctly every time. The address of any new account needs to use the following formula:
- address = rightmost_20_bytes(keccak (RLP (sender address, nonce)))
This function represents the statement that the Ethereum contract address follows from the yellow paper. The yellow paper is a blockchain which many people work on and is another name for the Ethereum Protocol. It states the following:
“The address of the new account is defined as being the rightmost 160 bits of the Keccak hash of the RLP encoding of the structure containing only the sender and the account nonce. Thus we define the resultant address for the new account….”
Instead of using that, you can easily use the formula given above to determine your missing Ethereum contract address. Below, I’ll go over the formula if you need help finding the information to fill in:
- keccak: An alternative algorithm to the one that Bitcoin uses. It computes the Ethereum-SHA-3, or Keccak-256, of any input.
- RLP: An encoder that allows objects in Ethereum to go in numerical order.
- Sender address: The contract or wallet you used to create this new contract.
- Nonce: The number of transactions sent from the sender’s address. It can also be the number of contracts made by the account.
How to Recalculate the Contract Address
If your new contract address is the first contract created from that address, the nonce value should always be one. However, if it’s the second or third, you should plug in a two or three, respectively, into the nonce section. The RLP value should be a range.
You then can plug your formula into a program, like Remix, to compute it for you. Your result should give you a hexadecimal string of numbers. Here’s an example:
- address public a = address(keccak256(0xd6, 0x94, YOUR_ADDR, 0x01));
This example gives us an address that looks like this:
- 0x048559A2982f50c268B80E14b1A98A1524295016
And there you have it – your Ethereum contract address! This method works every time because a consistent formula creates the address for you.
Of course, there are faster ways for you to find this information. You’ll probably only want to use this method if you’re in a pinch and have no other way to find the address. It can be frustrating for first-time developers.
This short video explains how to compute smart contract addresses:
https://www.youtube.com/watch?v=X1E2s6fDVJQ
Staying Safe Online
Since anyone can calculate any Ethereum contract address, it’s important to note that you’re not anonymous when using the platform.
Anyone can figure the contract address, follow your transactions, and view contract addresses you make later on. This fact is due to the formula above – it works to create all Ethereum contract addresses. You’ll need to know how to stay safe online while using Ethereum.
Finally, you’ll want to learn how to protect your money. People can predict future contact addresses to hide away funds since the addresses use a well-known formula.
If you send your money to one of these addresses that don’t technically exist yet, you lose it. The only way to get it back would be to make a contract with that exact address, which may be impossible. It’s best only to use verified contracts from a trustworthy source.
2. Use Etherscan To Find the Contract Address
You can also use the Etherscan platform to find the contract address, which is a quicker method than the one I’ve just shared with you. You can find the Ethereum contract address from the creator as long as you have access to this information. Here’s how to do it:
- Open Etherscan and log in.
- Look up your current contract’s address.
- Go to the “Internal Txns” tab.
- Find the most recent contract creation and click on it.
- Locate the contract address at the top left corner of your screen.
Now that you have the address, you can use it for many different purposes. You can complete transactions with the contract or end the contract. Since there are many different uses, it’s stressful when you lose the contract address.
Etherscan is a precious resource for many Etherum users. You don’t need to register an account to access their tools, and it’s completely free. It tracks transactions, allows you to check on contracts, and helps find out what you need to know on a blockchain. You can easily make use of it at any time.
Overall, this is the easiest method to use. If you don’t have an Etherscan account, you won’t need to register to use the site unless you want to. It makes it simple to locate various Ethereum contract addresses.
3. Call Back the Address
If you’re missing the contract address, you might be able to call it back. You also may be able to find it by looking over the last few transactions from your address.
To perform the call back, you can use the following codes:
- web3.eth.getTransactionReceipt(‘{txn_id}’)
- web3.eth.getCode(address)
With the first option, your result is the transaction receipt, which should have all of the information you need.
For instance, this code should give you the correct contract address and the blockchain number. You’ll want to make a note of the information somewhere, so you don’t lose it again.
The second returns the contract byte code or other addresses. It’s an efficient way to find the information that you’re looking for.
The Role of Ethereum Contract Address
Every Ethereum account has an address, and much like every email account, it has its unique address. This information is for finding the account, identifying it, and showing you important information about it. You need the Ethereum contract address to send funds to the account or complete other transactions.
It’s safe to give out the address to others. You’ll need to if you want to send and receive cryptocurrency with that person. No one can access your account just by having your address, although you still want to make sure you stay safe online.
Suppose you want to understand better how Ethereum works on the blockchain and how the contracts run.
Then, read the book Mastering Ethereum (available on Amazon.com). This book is the perfect reference guide for those new to Ethereum and programming. It includes many examples and information that can help you invest wisely.
Even if you don’t code, the first few chapters can still guide you through the process and teach you more about this cryptocurrency.
What Are Smart Contracts?
Smart contracts, which Ethereum uses, are programs that run on a blockchain. These programs complete various transactions by executing code. The smart contacts also hold onto Ether and keep track of it in a digital ledger.
When you create a new smart contract in the blockchain, it’s automatically assigned a new address. This address comes from the formula mentioned in method one; it comes from the creator’s address and the “nonce” of that address.
You can program a smart contract to do various things. You could have it release funds to someone’s account periodically, make it release payment upon confirmation of delivery, or have it automatically charge someone every month for a service. There are many possibilities when using a smart contract.
Overall, smart contracts are beneficial. These programs can automatically run code for completing transactions, making it much easier to manage your currencies. In other words, smart contracts are an essential part of learning to use Ethereum.
How Many Smart Contracts Can Ethereum Count?
Ethereum can count on up to 1.5 million smart contracts. The blockchain has been used for this in the past couple of years. However, accessing smart contracts’ code sources remains a challenge as transparency and open access given by public blockchains consider just data registered in the blocks.
Final Thoughts
In short, there are a few different ways that you can find an Ethereum contract address after you’ve lost it. You can recalculate it yourself, check Etherscan, or use some kind of call-back option. Once you have the new address, make sure not to lose it again!
An Ethereum contract address has many different purposes, although it’s mostly for keeping Ethereum transparent and honest.
The address contains a lot of information on previous transactions and contracts. Overall, the contract address refers to a specific place on the blockchain. When you have it, you can perform transactions with it.
Sources
- Ethereum: Ethereum Accounts
- Ethereum: Introduction To Smart Contracts
- Git Hub: Ethereum Yellow Paper
- Ethereum Classic Technical Reference: Root Hashes
- Ethereum Stack Exchange: How to find contract’s address?
- Youtube: How Ethereum smart contract addresses are computed?
- Arxiv: Smart-Corpus: an Organized Repository of Ethereum Smart Contracts Source Code and Metrics