ViaBTC | The Main Ethereum Testnets & ETH Faucets

I. Olympic (PoW)

The first-ever public Ethereum test network was called Olympic and was released in early 2015 before the official launch of the Ethereum mainnet. The testnet was primarily used to test the limits of the Ethereum operating environment when the network faces massive transactions. As the Ethereum mainnet went live, Olympic was officially abandoned in July 2015.

II. Morden (PoW)

After Olympic was discontinued, a new testnet was needed to help the mainnet run better, which triggered the birth of Morden in July 2015. The testnet was mainly used to test for junk data and certain basic issues between Geth and Parity, the two main Ethereum clients. After it was live for over a year, Morden was also discontinued due to the impact of the difficulty bomb.

III. Ropsten (PoW to PoS)

To solve the difficulty bomb problem that discontinued Morden, Ethereum developed another testnet called Ropsten, which is still running to this day. Back in 2017, Ropsten suffered a major attack. The attacker sent tens of millions of spam transactions and gradually raised the gas limit from 4,700,000 (the normal figure) to 90,000,000,000. People had no idea why the attacker hacked a worthless testnet, as the test coins had no real value. Some say that he did it purely out of curiosity and for fun.

IV. Kovan (PoA)

Following the Ropsten attack in 2017, Ethereum started to adopt multiple testnets in parallel to reduce the losses after a possible attack. As such, Parity, Ethereum’s wallet team, created a new testnet called Kovan. Unlike testnets mentioned above, Kovan uses PoA to enable enhanced security. This consensus mechanism makes the testnet safer by maintaining a small group of trusted signers and validators at the expense of decentralization. Today, Kovan remains live and has become the favorite testnet of many developer teams in the Ethereum community.

V. Rinkeby

Rinkeby, a testnet provided by Ethereum, also uses PoA. However, unlike Kovan, the Ethereum team has provided Rinkeby’s PoA documentation. In theory, any Ethereum wallet can support the Rinkeby testnet based on this documentation.

VI. Goerli

Goerli, launched in 2018, is also one of the major testnets for the 2.0 upgrade. According to the developer roadmap, the Ethereum mainnet will soon merge into PoS if the Goerli merge is successful.

VII. Kiln

As a public testnet released by the Ethereum Foundation this March, Kiln resembles the Ethereum mainnet. Its execution layer, which uses PoW, is launched in parallel with the beacon chain, which runs the PoS mechanism. At the moment, Kiln has fully shifted to PoS. Also included in the discontinuation list announced in June, the testnet will be closed soon after the Ethereum mainnet transitions to PoS.

VIII. Sepolia

Sepolia is the testnet that merged into PoS and started its trial operation after Ropsten. Launched in October 2021, the testnet has completed its merge. Sepolia and Goerli are both critical as they will serve as testnets for the deployment of Ethereum DApps in the future.



Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store


Via Bitcoin, Making World a Better Place.