Short answer. A testnet is a separate copy of a blockchain used to test apps and upgrades without real money. Tokens on a testnet have no value and come free from faucets. For Ethereum in 2026, the maintained public testnets are Sepolia, for apps, and Hoodi, for validators and upgrades. Older testnets such as Goerli and Ropsten are deprecated.
Last updated 30 October 2026
Why Are Testnets Useful?
Developers use testnets to test their apps. For non-developers, the main benefits of testnets are as follows:- Educational tool and risk-free practice: In the crypto space, often the best way to learn is to ‘do’. However, this can be costly in the event of an error on mainnet. Testnet environments are perfect for learning as you can practice with valueless cryptocurrencies. You can get comfortable with performing actions such as sending or swapping cryptocurrencies, or providing liquidity, all in a risk-free setting. (Read ‘Using Testnets as a Learning Tool’ for more.)
- Opportunities for airdrops: Projects often reward users for testnet feedback, and can also be a way to become eligible for future airdrops should the project issue a token. By connecting your wallet and performing specific actions, you’re logging your Ethereum address (‘0x’ or ‘ETH’ address) with the testnet app’s smart contracts. As blockchains like Ethereum are public, the developers can track which addresses have connected to the app and performed certain actions. Projects will “take snapshots” of the smart contracts at certain block heights to get a list of the app’s historical user base. Becoming eligible for airdrops is often as simple as logging your ETH address on the platform.
Examples of Testnets
| Blockchain (or sidechain) | Testnet(s) |
|---|---|
| Ethereum | Ropsten, Kovan, Rinkeby, Goerli |
| Polygon | Mumbai |
| Solana | Devnet, Testnet |
| Binance Smart Chain | Binance Smart Chain testnet |
| Avalanche | Fuji |
| Energy Web Chain | Volta |
| Celo | Alfajores, Baklava |
| Polkadot | Rococo |
| Moonbeam | Moonbase Alpha |
| Huobi Eco Chain | Huobi Eco Chain testnet |
| Acala | Mandala |
Getting Testnet Tokens From Faucets
When using a testnet, valueless cryptocurrency is distributed to testers to use as ‘play’ money to transact and try products or apps. Testnet tokens are obtainable through faucets. You’ll typically need to get test versions of the blockchain’s native token (e.g. ETH) and the app’s native token. (Note: to mint testnet funds you’ll often need ETH). Examples of testnet faucets: Kovan, Rinkeby, Ropsten, Goerli, Chainlink, Binance Smart Chain, Polygon, Terra, Aave v1, Huobi Eco Chain, Hop Exchange By default, MetaMask is connected to Ethereum’s 4 testnets. For non-Ethereum testnets, you must first add a custom remote procedure call (RPC). To connect, input the required information such as network name, new RPC URL and Chain ID. Chainlist is a list to help you connect your wallets with EVM-compatible blockchains and testnets.Guided Walkthroughs
Below are links to 2 member-only walkthroughs recorded by research analyst Nathan Gurr.Risks & Tips
- Testnet tokens are valueless. Be careful not to mix up your different ETH balances.
- Ethereum addresses and private keys that work on Ethereum, work on each testnet so be extremely careful not to send ETH or tokens on the Ethereum mainnet to a testnet address. You’ll lose your assets if you do. Same goes for other blockchains or testnet funds.
- Use a dedicated address or account for testnets, similar to airdrops and to avoid sending real ETH to a testnet. To mitigate the risk of being scammed, vet the project that’s running the testnet.
- When connecting to a custom network, verify that the details are from a trusted source.
Testnets in 2026: what has changed
Several testnets named in this guide have since been shut down. According to ethereum.org (October 2026), the two public Ethereum testnets client developers maintain are Sepolia, the default for application testing, and Hoodi, for validator and protocol upgrade testing. Goerli, Rinkeby, Ropsten and Kovan are deprecated, and Holesky was deprecated in September 2025. Layer 2 networks now run their own testnets alongside Sepolia, such as Arbitrum Sepolia and Optimism Sepolia.
Testnets remain where major upgrades are rehearsed. In September 2026, the Research Hub recorded that Solana’s Alpenglow consensus upgrade, which targets 150-millisecond settlement, went live on devnet and public testnets before any mainnet launch.
- Sepolia: Ethereum app testing.
- Hoodi: Ethereum validator and upgrade testing.
- Goerli, Rinkeby, Ropsten, Kovan and Holesky: deprecated.
- Never reuse a mainnet wallet holding real funds for testnet experiments.
How Collective Shift uses testnet milestones in research
The research team treats testnet launches as milestones on the way to mainnet, not as finished products. Before Ethereum’s Dencun upgrade in 2024, the team’s February 2024 article explained what the successful testnet rollout would mean for users once Dencun reached mainnet.
- A testnet launch is a milestone, not a launch.
- Watch for mainnet dates and audits.
- Testnet tokens have no value.
“For users, it’ll be significantly cheaper to transact on L2s after Dencun.”
Collective Shift research team, Ethereum Much-Needed Upgrade Draws Closer After Testnet (February 2024)
Where this guide comes from
This guide is written and reviewed by the Collective Shift research team. Collective Shift is a crypto research and education company founded in 2020 in Melbourne, and a research and education partner to Coinbase, Swyftx and CoinSpot. Sources used in this update:
- Collective Shift Knowledge Hub: Research Hub: Solana’s Alpenglow upgrade reaches public testnets (27 Sep 2026) (ref 93676f8d), original source: www.coindesk.com
- Collective Shift Knowledge Hub: Ethereum Much-Needed Upgrade Draws Closer After Testnet, Collective Shift (Feb 2024) (ref f7e8882e), original source: collectiveshift.io
- Collective Shift Knowledge Hub: Research Hub: DogeOS launches public testnet (1 Oct 2026) (ref 830d619a), original source: decrypt.co
- Official documentation: ethereum.org: Networks (Oct 2026)
Last updated 30 October 2026. General information only, not financial advice. Consider your own circumstances and seek professional advice before making investment decisions.
Frequently Asked Questions
Which Ethereum testnet should I use in 2026?
Ethereum.org recommends Sepolia for app and smart contract testing and Hoodi for validator and protocol upgrade testing.
Is Goerli still available?
No. Goerli is deprecated, along with Rinkeby, Ropsten and Kovan. Holesky was also deprecated in September 2025.
Do testnet tokens have value?
They are meant to have no value and are given out free by faucets. Be wary of anyone offering to buy or sell them.