Ethereum's Ropsten Testnet: A Complete Guide
Written by Shray Jain
Reviewed by Brady Werkheiser
The Ethereum-based testnet, Ropsten, enabled developers to experiment with protocol upgrades and decentralized applications before their deployment on the Ethereum mainnet. The testnet was similar to the PoW mainnet before the mainnet transitioned to the PoS consensus model due to its proof-of-work consensus model.
It’s essential to know the testnet merged with the Ropsten Beacon Chain on June 8, 2022, when the Terminal Total Difficulty (TTD) of 50000000000000000 was reached. Because of this merge, developers are advised to use alternative testnets like the Sepolia network to test their applications and nodes in a post-merge environment.
Note: The Ropsten testnet was deprecated on October 5, 2022.
Deprecation Notice
While you can use the Goerli testnet, we caution against it as the Ethereum Foundation has announced that Goerli will soon be deprecated. Therefore, we recommend using Sepolia testnet as Alchemy has full Sepolia support and a free Sepolia faucet.
What is the Ropsten testnet?
The Ropsten testnet, which is now deprecated, is an Ethereum-based test blockchain used by Ethereum developers to test protocol upgrades before deploying applications on the Ethereum mainnet.
Ropsten supported node clients such as:
Geth
Parity
Nethermind
Hyperledger Besu
Because it was a testnet on the Ethereum network, there was no direct fiscal tie with the mainnet, which means that developers don’t need to worry about the implications of transactions and the cost of testing applications on the testnet.
As the expense of erroneous implementations on the mainnet can be relatively high, it’s important for web3 developers to have access to a sandbox-like environment where the cost of a mistake or failure is negligible.
When was Ropsten launched?
Ropsten launched in November 2016 as the official successor to Morden, the first Ethereum testnet based on a PoW authority consensus model. The Ropsten testnet has a chain and network ID of 3.
Using a PoW consensus mechanism, the Ropsten testnet relied on all nodes to verify the computational effort a single node expended. This thwarted certain economic attacks on the network because miners had capital at risk.
However, Ethereum core developers merged the PoW mechanism with the Ropsten Proof of Stake Beacon Chain to prepare for Ethereum’s mainnet merge. The Ropsten testnet was primarily used by core developers for testing upgrades to underlying protocols. Like so many other testnets on the Ethereum blockchain, the Ropsten testnet was maintained by the Geth developer team.
How big was the Ropsten testnet?
As of May 2022, there were approximately 12.3 million blocks on the Ropsten testnet, and developers had executed roughly 230 million transactions.
The block time on the Ropsten testnet was below 30 seconds, and 15 miners had governance power, with 1 possessing 94.5% hash power.
The maximum block gas limit stood at 50,000. This represents the highest price a cryptocurrency will distribute when a smart contract is executed, or a transaction is sent on the Ethernet blockchain.
The gas price was about 146,602 Gwei with an average burn of 23.66 Gwei per block. To date, ~113,440 ETH was burned on the Ropsten testnet.
Why did developers use the Ropsten testnet?
Developers used the Ropsten testnet because it best mimicked the production environment of the Ethereum mainnet when it was based on a PoW mechanism and to prepare for the Ethereum mainnet merge.
Miners on the Ropsten test network had a financial incentive to maintain the testnet itself, given its resemblance to the mainnet at the time. Moreover, the testnet provided helpful information about certain issues faced on the mainnet, such as the relationship between gas prices and uncle block rates. It was also useful for decentralized application development as Ropsten provided realistic back-end and front-end performance tests.
In February 2017, the tesnet experienced a denial-of-service (DoS) attack where spam blocks were inserted into the network and were slow to process, requiring much CPU, time, and memory. This attack on Ropsten meant that connecting an Ethereum client to the Ropsten testnet was slow and consumed excessive disk space as the attack added 10 GBs of bloat to the distributed database.
In this instance, the Ropsten testnet demonstrated a vulnerability to spam attacks, indicating instability and unreliability. The Ropsten network was revived with new security provisions to combat similar threats. Until it was deprecated, no serious incident was reported on the testnet.
What happened to the Ropsten testnet after the Merge?
The Ropsten testnet merged on June 8, 2022, when the Terminal Total Difficulty (TTD) of 50000000000000000 was reached, and it is no longer updated (i.e., it is now deprecated). Instead, Ethereum recommends developers use the Sepolia and Goerli testnets. While the Sepolia testnet is a PoS testnet, the Goerli testnet is a proof-of-authority testnet that can work across different clients.
The Ropsten testnet merge was a vital testing milestone in anticipation of the Ethereum merge when the mainnet merged with the beacon chain PoS system. In effect, the Ropsten testnet merge simulated the eventual merge on the mainnet.
Marking the end of PoW for the Ethereum network, the Merge ensured a complete transition to a PoS consensus. PoS consensus mechanism reduced the need for energy-intensive mining activity. It also helps facilitate user participation in securing the overall network, which further promotes decentralization and will augment crypto-economic security relative to the PoW model.
Nevertheless, switching to a PoS model presents the following disadvantages:
The PoS consensus model is newer compared to the PoW model
End-users need to run more pieces of software on the PoS model which involves an execution layer and a consensus layer (formerly known as ETH2)
PoS implementation is more complex than PoW
Where can I get test ETH since Ropsten faucets are deprecated?
Historically, developers could request testnet ETH on the Ropsten testnet using a Ropsten faucet, but because the network is no longer supported, it is recommended to use other testnets and faucets, such as Sepolia and Goerli, to test dApps on Ethereum.
The two recommended testnets and faucets are Sepolia, which reflects most closely the post-merge development environment on Ethereum, and Goerli, a PoA test network.
To support Web3 developers, Alchemy maintains a Sepolia faucet and a Goerli faucet, which provide extra fake ETH when users sign up for a free Alchemy account.
An Ethereum faucet enables developers to obtain testnet ETH, which has no real-world value. Developers can use this testnet ETH for experimentation purposes on a decentralized application or protocol before deployment on the mainnet, where financial risks are real.
Saying Goodbye to the Ropsten Testnet
The Ropsten testnet provided tremendous value to Ethereum developers since its launch in 2017 through the Ropsten merge until it was deprecated last year.
From giving developers a safe testing environment for building applications to helping core developers plan and test for the mainnet merge, the Ropsten testnet has been a key web3 infrastructure for many web3 developers.
Related overviews
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