Metamask: the ultimate guide to the Ethereum wallet

The Ethereum blockchain offers multiple services and is supported by many cryptocurrencies. However, managing this broad spectrum of possibilities would be impossible without a wallet like Metamask. Let’s find out what this tool is in order to understand how it facilitates access to the crypto ecosystem. In this article, we will explain how Metamask works as well as how to use it to get the most out of decentralised applications (DApps).

What is Metamask?

The blockchain is a registry of information. Although it is public and transparent, it is also difficult to read and consult. This explains the need for a tool that helps us find and process information we need from this database, as well as allowing us to carry out transactions on the blockchain easily and instantaneously. This explains what a wallet is, essentially a program that facilitates the control and use of cryptocurrencies on the blockchain.

It was for this very purpose that the Metamask wallet was created in 2015. It was developed by Aaron Davis while working for ConsenSys, an organisation that builds infrastructure for Ethereum (founded by Joseph Lubin). If the name sounds familiar, it is because Lubin also contributed to the birth of Ethereum, alongside Vitalik Buterin.

At this point, you may be wondering what Metamask is and how it works on a technical level. In practice, it is software configured as a browser extension and a smartphone application. If we want to give a more specific definition of what kind of wallet Metamask is, we can say it is a hot wallet, as it is connected to the internet. Apart from that, this wallet requires the owner to guard his or her own access keys. In other words, it is a non-custodial wallet. Specifically, Metamask only asks users to store their Seed Phrase: a set of 12 random words from which the cryptographic keys are derived. They allow access to the wallet from any device.

Metamask can also be defined as a multichain application, which makes it quite practical for those using different networks. Which blockchains and thus which cryptos does Metamask accept? In short, the Ethereum coin (ETH) and all ERC-20 and ERC-721 tokens. These are built on the same blockchain and are utility tokens and NFTs respectively. However, Metamask can also interact with Ethereum’s Layer 2s, such as Polygon (MATIC), Arbitrum and Optimism. It also supports blockchains with ETH-compatible languages, including Avalanche (AVAX) and Fantom (FTM). In fact, the wallet accepts cryptocurrencies issued by all of these networks.

As it supports multiple networks and coins, Metamask is very convenient as a wallet to use for DApps. Beyond that, a wallet like Metamask is necessary to use most DApps, and there are very few custodial services that offer the same level of compatibility and flexibility (such as Phantom and Trust Wallet). It should not surprise us that Metamask does not support Bitcoin, because there are few DApps on Satoshi Nakamoto’s blockchain.

How to create a Metamask wallet: browser or mobile app

To understand how Metamask works, you must first create an account. There are two options, as stated in the title of this section. You can either download the browser extension that is available on Google Chrome, Firefox, Brave, Edge and Opera, or search for the app in the store of your Android or iOS smartphone. On the web, be sure to download the app through the official website (metamask.io). Also for smartphones, verify the authenticity of the app, because scammers may attempt to steal cryptocurrencies through fake pages and products; always beware of online scams!

Whichever solution you choose, web or mobile, once the download is complete, you will have to follow this two-click path: “Get Started” > “Create a Wallet”. You will then be able to choose a password for your account.  With the next step, you will then be shown your Seed Phrase, also called the Secret Recovery Phrase because it allows you to reset your password if you forget it. Anyone who knows this secret combination is able to access your Metamask account as well as the funds stored in it. Store your Seed Phrase in a secure manner, preferably offline, by following this password management guide.

Metamask itself will then ask you to confirm the combination, to ensure that you have written the Seed Phrase. Enter the words that make up your secret phrase in the right order from the suggestion on the screen. Remember that no one but you should know this information, so if you forget it, there is no way to recover your funds!

How does Metamask work?

Metamask performs the basic function of any wallet: it facilitates the use of public and private keys and assigns an address to the user so that cryptocurrencies can be sent and received safely. Let’s help you grasp the concept with a more ‘traditional’ example: to make a purchase, you could use a credit card, which carries an identification number, expiry date and security code. Similarly, Metamask helps you carry out transactions on blockchain, by recording the information you need in a web extension or app.

The web interface presents 3 options: buy, send and exchange. The mobile version adds the receive function, which is essentially a QR code so you can easily share your wallet address. Alternatively, on both smartphones and desktops, if you look immediately above, you can find the wallet address written, as well as the network you are operating on. You can change this parameter from a drop-down menu, where you can select or add your desired network. If the wallet is ‘not connected’ on the screen, it means that it is not yet associated with any Dapp. We will see later how to connect Metamask to Opensea and other decentralised applications.

Before we tackle in detail how Metamask works, by simulating the sending and ‘swapping’ of cryptocurrencies, we need some funds. So, how can you ‘put money’ on Metamask? The wallet allows you to buy directly with fiat currencies. The ‘buy‘ button redirects you to some solutions to buy crypto via bank transfers, credit cards or services such as Apple and Google Pay. Alternatively, you can deposit cryptocurrencies by transferring them from other wallets, such as the one integrated in the Young Platform exchange. Copy the address of your Metamask wallet and follow this guide!

To withdraw from Metamask, or to send cryptocurrencies to another wallet, the process is simple. Click on ‘Send‘, enter the destination address, select the crypto to be exchanged and the amount. See the support guide to understand how to send funds to your account on the Young Platform exchange.

Since sending is a transaction conducted on the blockchain, a gas fee must be paid. This is a commission to the node in charge of recording the information in the next block created. You can set the cost manually, choosing between Low, Medium and High levels. Transactions accompanied by higher gas fees will be faster, because validators assign precedence according to the fee. This has particular importance in situations of network congestion.

Finally, Metamask allows you to exchange ETH for ERC-20 tokens and vice versa, or the latter for each other. This is an operation called a ‘swap‘, and it takes place directly in your wallet. In practice, Metamask works like an aggregator of decentralised exchanges, like 1inch for example. It automatically searches for the most advantageous exchange among a number of DEXs, in terms of price and commission. Metamask monitors several swap platforms, including Uniswap, Curve and 1inch itself, also providing slippage protection.

How to connect Metamask to Opensea

In general, to connect your wallet to a DApp, search for the relevant website, launch the application and find the “connect wallet” button on the next screen. Connecting to Opensea is actually much more straightforward. Select Metamask in the “Profile” section on the top right, and enter your wallet password. In a quick and easy way, you can immediately explore the main marketplace for NFTs.  

Your wallet on Opensea corresponds to your personal account, allowing you to approve all the actions you can perform on the platform: a pop-up will allow you to ‘sign’ with your private key. Though, specifically, what is the purpose of linking Metamask to Opensea?

First of all, Opensea can be a showcase for your NFTs. If you have them connected in your Metamask wallet, you will automatically find them in the ‘collected’ section of your profile on the marketplace. Therefore, anyone will be able to see them and add them to their favourites, an action always authorised through the wallet. Furthermore, on Opensea, you can sell NFTs you keep in Metamask and buy more to add to your collection, all in a few simple clicks.

Finally, Metamask can also give you access to the world of video games. It allows you to connect, for instance, to the metaverses of The Sandbox or Decentraland. With a single wallet, you can carry out the transactions required by several games and keep the items you earn and avatars in the form of NFTs. 

How to use Metamask: advantages and disadvantages

Metamask makes the universes of DeFi and Web3 more accessible by storing the information users need to interact with Dapps. We know that wallets protect private keys, but is Metamask secure? The mobile application and web extension are based on open-source code, so anyone can audit it, looking for potential vulnerabilities. Public audits of the software are a guarantee of transparency, but security is also the user’s responsibility. The real weakness is inherent in the devices where the wallet is downloaded. 

Make sure your computer is not compromised by viruses and use Metamask carefully. Do not connect to suspicious DApps: can you recognise crypto scams? Likewise, keeping your Seed Phrase secret is your job. Note that Metamask does not store your private keys in centralised servers, but stores them in your computer’s browser or in the internal memory of your mobile device.

Other advantages of Metamask are its popularity and interoperability. It supports the main networks of the Ethereum ecosystem and is compatible with most DApps. The interface is simple, suitable for beginners, and the software does not involve any additional downloads. There is no need to download the entire Ethereum blockchain database, because Metamask relies on external nodes that already participate in the network. 

Metamask also allows you to generate multiple wallets. Click on ‘create account’ in the ‘My Accounts’ section at the top right, and you get a new address. It will be linked to a different private key, but controlled by the same Seed Phrase. In addition, this opens up the possibility of connecting a Hardware Wallet, such as Trezor or Ledger. This simplifies the management of cryptocurrencies administered through physical devices, simply by entering the relevant Seed Phrase.

Possible disadvantages stem from the online nature of Metamask. Although the developers can readily fix bugs, the Internet unfortunately hides many pitfalls. Therefore, many users prefer to transfer funds to the wallet only when they plan to use them in the short term. It is therefore not the best solution for you if you want to store crypto for a long time. Hardware wallets are probably a better alternative for this. Moreover, Metamask users cannot rely on customer services that are offered in centralised exchanges. 

Finally, Metamask does not have a utility token, unlike Trust Wallet (TWT), another crypto software wallet. This token could give governance powers back to users, such as TWT holders being able to intervene in decisions such as adding new networks. It could also grant discounts on fees related to purchase and swap transactions. Although the Metamask community waits, hoping for an airdrop, this does not seem likely to happen in the near future.

Now that you know what Metamask is, how it works and how to use it, we can close this short guide with a fun fact. The logo is a fox, a polygonal mask that will follow your cursor (have fun on metamask.io!). The cunning and mysterious nature of this animal thus reminds us to remain discreet and vigilant when using our wallet.