As I listened in to a recent weekly meeting at ELI5 DAO, the topic of testnets came up. During this conversation, I realized I know very little about crypto testnets, and thus this article was born. Today we are taking a look at testnets, why they exist, how they contribute to the overall advancement of blockchain technology, and how to access them.

What is a TestNet?

A testnet, short for “Test Network,” is a parallel blockchain network that contains the important features of the mainet, which developers use to test and experiment with new cryptocurrencies, decentralized applications (DApps), and smart contracts before deploying them on the mainnet. Unlike the mainnet, testnets have no real-world value and are designed solely for development and debugging purposes.

Benefits for Developers

Testnets offer a risk-free sandbox for experimentation, development, and fine-tuning. This allows developers to identify and fix potential issues, vulnerabilities, or bugs without risking real assets or compromising the security of users. Additionally, early testing and debugging significantly reduce the likelihood of costly errors and enhances the overall stability of the blockchain. It’s a great way to get the broader community involved in testing projects and recieve feedback in a realistic testing environment.

At the blockchain level, testnets are valuable for assessing the scalability of a blockchain network. By simulating a large number of transactions, developers can understand how the network performs under heavy load, allowing them to optimize its performance accordingly.

Benefits for the Broader Web3 Community

In addition to the benefits for the developer community, some DApps offer testnet operations so you or your organization can try things out prior to committing or risking real-world assets. Or perhaps you love new tech and want to test the latest and greatest DApps in development. You can get involved in a risk-free way on a testnet and provide feedback to help further the development of your favorite projects.

How to Access Testnets

Photo by Cookie the Pom on Unsplash

Testnets provide developers and users free tokens (aka “test coins”) to simulate transactions and test functionalities without needing real funds. Test coins are acquired via faucets, web services that distribute the test coins upon request (More on where to find faucets below). The test tokens can be added to your crypto wallet of choice (we recommend a separate wallet just for testnet use) and are utilized for transactions in the same way real tokens are.

One thing to remember is that testnets get depreciated over time, meaning they shut down. Testnets are intended to be temporary and should not be relied upon long-term. The reasons that testnets are depreciated vary from new features of a mainnet blockchain that need to be integrated into a new testnet, to token limitations or scarcity, where test coins are difficult to come by, as is the case with the popular Ethereum testnet, Goerli. Due to this, developers occasionally need to transition their test applications to a newer or alternative testnets. So don’t get too comfy and hoard those valueless testnet coins. Chances are the testnet you are using will be depreciated at some time in the future. In fact, it’s common curtesy to send any unused test tokens back to the faucets from which they came so others can use them. Most faucets have instructions on how to do this.

Popular Testnets

Photo by Kanchanara on Unsplash

Ethereum Testnets: The two public testnets that client developers are currently maintaining are Sepolia and Goerli. With that said, Goerli is depreciated and moving projects to Sepolia is recommended before the end of 2023.

Sepolia Faucets:

QuickNode Sepolia Faucet

Sepolia Faucet

Coinbase Wallet Faucet

Alchemy Sepolia Faucet

Goerli Faucets:

QuickNode Goerli Faucet

Alchemy Goerli Faucet

Bitcoin Testnet: There have been three generations of testnet. Testnet3 is the current test network.

Testnet3 Faucets:

Polygon Testnet: The Polygon testnet is called Mumbai, which is a layer-two (L2) scaling platform for Ethereum.

Mumbai Faucet:

QuickNode Mumbai Faucet

Chainlink Faucet

There are many more TestNets in existence for the various blockchains. A quick Google search will point you in the direction of where to find them.

In the fast-evolving world of blockchain and cryptocurrencies, testnets serve as invaluable tools for developers to ensure the reliability and security of their projects before going live on the mainnet and undoubtedly contribute to the advancement and widespread adoption of blockchain technology. Testnets will remain essential in fostering innovation and refining decentralized solutions for a better digital future as the crypto space continues to grow.


Don’t forget to subscribe and follow me on Twitter to be notified when new articles are posted. Have ideas about what you’d love to see featured in future entries? Send me a tweet!

Follow me on:

Twitter: Erin @ the Decentralized Diary


Medium:‍ is a directory 🗒 for decentralized resources. It includes resources such as the List of DAOs, List of DAO Tools, and the Decentralized Diary. Visit our website at or follow us on Twitter @decentra_list.

‍The content is for informational purposes only. Nothing contained in this article constitutes a solicitation, recommendation, endorsement, or offer of a security, token, or application. This is not investment or legal advice. Please do your own research.