Como usar MetaMask
A step-by-step guide to installing MetaMask, creating and backing up a wallet, adding networks, sending and receiving crypto, and connecting to DeFi apps without getting scammed.
O que é MetaMask?
MetaMask is a self-custodial crypto wallet. It lets you hold, send and receive ETH and ERC-20 tokens, and connect to decentralized applications (dApps) on Ethereum and other EVM-compatible chains (EVM stands for Ethereum Virtual Machine, the software that runs Ethereum smart contracts). It is available as a browser extension for Chrome, Firefox, Brave and Edge, and as a mobile app for iOS and Android. It is one of the most widely used wallets in crypto.
"Self-custodial" means you control the private keys: not a company, not an exchange, not MetaMask itself. Access to your funds rests on a 12-word seed phrase that only you hold. That is different from keeping crypto on Coinbase or Binance, where the exchange holds the keys for you.
MetaMask is also your entry point to DeFi. It connects to protocols such as Uniswap and Aave and to many other decentralized applications. Swapping tokens, lending, providing liquidity or earning yield all start with a connected wallet.
Auto-custodial
You hold the private keys. No third party can freeze or move your funds without your seed phrase.
Multi‑Rede
Switch between Ethereum, Arbitrum, Base, Polygon, Optimism and other EVM-compatible chains from the network menu.
Gateway dApp
Connect to DeFi protocols, NFT marketplaces and other Web3 apps from your browser or phone.
Instalando MetaMask
MetaMask comes as a browser extension and as a mobile app. The most important rule: start every install from the official website, metamask.io (see Sources). Fake MetaMask extensions and apps are a common phishing tool. They look like the real thing and steal your seed phrase the moment you type it in.
Extensão de Navegador (Recomendado)
Go to metamask.io, open the download page and pick your browser (Chrome, Firefox, Brave or Edge). You are sent to the official extension store for that browser. Add the extension and confirm the install. The MetaMask fox icon appears in your browser toolbar.
Verification tip: in the extension store, check that the publisher is MetaMask and that the listing is the one linked from metamask.io. Never install MetaMask from a link in an email, a Discord message or a social media ad.
Aplicativo móvel (iOS & Android)
Open the App Store (iOS) or Google Play (Android) and search for MetaMask, or follow the store links from metamask.io. Check that the publisher is MetaMask (the company behind it is Consensys). The mobile app includes a built-in browser for using DeFi apps from your phone.
You can bring your existing browser wallet to mobile by importing its seed phrase, or create a separate wallet on mobile.
Criando sua carteira
After installation, MetaMask walks you through wallet creation. The seed phrase backup is the step that matters most; take your time with it.
Concordar com os Termos & Criar Senha
Choose to create a new wallet and accept the terms. Set a strong password (MetaMask requires at least 8 characters; longer is better). The password only unlocks the wallet on this device. It is not your seed phrase and cannot recover the wallet on another device.
Faça backup da sua frase semente
MetaMask shows a 12-word Secret Recovery Phrase (seed phrase). Write the 12 words on paper in the exact order shown. Do not take a screenshot. Do not store it in a notes app or a cloud service. The phrase is the master key to the wallet: anyone who has it can take all your funds from any device.
Confirme sua frase semente
MetaMask asks you to re-enter some of the words to confirm you wrote them down correctly. Select them in the right order. This check makes sure you have a working backup before you use the wallet.
Carteira Pronta
Your wallet is ready. You see your address (it starts with 0x), a balance of 0 ETH and the main MetaMask view. You can now receive crypto, add networks and connect to DeFi applications.
Por que sua frase-semente importa
- The seed phrase is the only way to recover your wallet if you lose access to your device. Lose the phrase and the funds are gone for good.
- Never share the seed phrase with anyone. No legitimate service, support agent or dApp will ever ask for it.
- Store it offline: written on paper or stamped on metal, ideally in a safe. Never in email, cloud storage or a file on your computer.
Adicionando Redes ao MetaMask
MetaMask connects to Ethereum mainnet by default, but you will probably want Layer 2 networks such as Arbitrum, Base, Optimism and Polygon for cheaper transactions. Gas fees on these networks are a small fraction of mainnet fees; ethereum.org explains why (see Sources).
MetaMask includes a list of popular networks that you can enable from the network menu. For a network that is not on the list, chainlist.org is a widely used directory: connect MetaMask, search for the network and add it. The parameters (RPC URL, chain ID, currency symbol) are filled in for you. You can also enter them by hand; the MetaMask support site explains how (see Sources).
| Rede | Tipo | Fee Level | Melhor para |
|---|---|---|---|
| Ethereum | L1 (padrão) | Mais alto | Transações de alto valor, máxima segurança |
| Arbitrum | L2 (Rollup otimista) | Baixo | DeFi, negociação, uso geral |
| Base | L2 (Rollup otimista) | Baixo | Ecossistema Coinbase, taxas baixas |
| Polygon | Sidechain (PoS) | Muito baixa | Low-cost transactions, gaming |
| Optimism | L2 (Rollup otimista) | Baixo | DeFi, governança, aplicativos Superchain |
Fee levels are relative and move with demand; check a live gas tracker before a large transaction. To move tokens between networks you need to bridge your crypto, for example sending USDC from Ethereum to Arbitrum to use it with lower fees.
Recebendo & Enviando Cripto
Once the wallet is set up, you can receive tokens from an exchange, a person or a DeFi protocol, and send tokens to any address on the same network. Here is how each direction works.
Recebendo Cripto
Copy your wallet address from the account view in MetaMask (tapping the address copies it). It looks like 0x1a2B...3c4D.
Give the address to the sender: paste it into the exchange withdrawal form or send it to the person paying you. The address is public and safe to share, like a bank account number.
Make sure the sender uses the right network. If someone sends USDC on Arbitrum while MetaMask is showing Ethereum, you will not see the tokens until you switch to Arbitrum. They are not lost; they are on another chain.
Enviando Criptomoedas
Choose Send in MetaMask and paste the recipient's address. Check it twice: transactions cannot be reversed, and funds sent to a wrong address are lost.
Select the token and enter the amount. MetaMask shows the estimated gas fee. On Ethereum mainnet the fee depends on current demand; on a Layer 2 such as Arbitrum or Base the same transfer costs a small fraction of that.
Review the details and confirm. The transaction is broadcast to the network. Track it from the activity list in MetaMask or by searching the transaction hash on a block explorer such as Etherscan.
Want to understand why gas fees vary so much? Read our guide on what gas fees are and how they work.
Tem USDC no seu MetaMask?
Ganhe 7,50% de APY em USDC com a Poupança em Dólar da Coinstancy. Os juros são acumulados a cada segundo e reinvestidos automaticamente. Sem período de bloqueio, saque a qualquer momento.
Comece a ganhar 7,50% de APYConectando MetaMask a aplicativos DeFi
Most of what you do with MetaMask happens through DeFi apps. Here is how a connection works and what to expect at each step.
Como conectar (etapas universais)
Open the dApp's official website (for example app.uniswap.org, app.aave.com or app.coinstancy.com). Type the URL or use a bookmark. Do not follow links from Discord, Telegram or email.
Use the dApp's connect wallet option and pick MetaMask from the list. A MetaMask window opens asking you to approve the connection.
Review which accounts the dApp wants to see and confirm. A connected dApp can read your address and balances but cannot move funds without a separate signature from you.
When you act (swap, deposit, lend), MetaMask opens a window describing the smart contract interaction and the gas fee. Read what it will do, then confirm or reject.
Uniswap
Swap ERC-20 tokens on Ethereum, Arbitrum, Base, Polygon and Optimism. One of the largest decentralized exchanges.
Trocas de tokenAave
Empreste e tome emprestado cripto. Deposite tokens para ganhar juros, ou tome emprestado contra seus ativos como garantia.
Empréstimo & EmpréstimoCoinstancy
Ganhe 7,50% APY em USDC com a Poupança em Dólar. Os juros acumulam a cada segundo e são reinvestidos automaticamente. Sem período de bloqueio, saque a qualquer momento.
Rendimento em USDCMelhores Práticas de Segurança
Self-custody gives you full control and full responsibility. These habits protect a MetaMask wallet from the most common attacks. For more depth, read our crypto security guide.
Nunca compartilhe sua frase semente
No legitimate service, support agent or website will ever ask for your 12-word seed phrase. If anyone asks for it, it is a scam, without exception.
Use uma carteira de hardware
For any amount you would hate to lose, pair MetaMask with a hardware wallet such as a Ledger or Trezor. The private keys stay on the device, so a compromised computer cannot sign on its own. MetaMask supports hardware wallets directly: connect the device and add its account (see the Ledger and Trezor docs in Sources).
Revogar Aprovações de Token
When you approve a contract to spend your tokens, the permission stays active until you revoke it. Use revoke.cash to review and revoke old approvals. This limits the damage if a contract you once approved is later exploited.
Detectar Tentativas de Phishing
Bookmark the official URLs of the dApps you use. Phishing sites copy DeFi interfaces closely. Check the address bar before you sign anything. MetaMask includes phishing detection that warns you about known malicious sites, but it cannot catch every new one.
Ganhe 7,50% APY em USDC
Coloque seus USDC para trabalhar com a Poupança em Dólar da Coinstancy. Os juros acumulam a cada segundo e são reinvestidos automaticamente. Sem bloqueio, saque a qualquer momento.
Comece a ganhar na CoinstancyAlternativas ao MetaMask
MetaMask is the most common choice, but several alternatives address specific needs. Here is a short comparison of popular options.
| Carteira | Melhor para | Plataformas | Recurso Principal |
|---|---|---|---|
| Rabby | Usuários avançados & DeFi | Navegador, móvel | Simulação pré-assinatura, troca automática de rede |
| Rainbow | Usuários mobile-first | iOS, Android, navegador | Simple interface, ENS names, portfolio view |
| Carteira Coinbase | Usuários Coinbase | Navegador, móvel | Entrada fácil de fiat, nativo da rede Base |
| Carteira Trust | Iniciantes multi‑cadeia | iOS, Android, navegador | Many non-EVM chains, built-in staking |
All of these wallets are self-custodial and work with the same DeFi apps as MetaMask. A seed phrase is portable: you can import an existing MetaMask wallet into Rabby or Rainbow without moving any funds. The choice comes down to interface, features and workflow.
Perguntas Frequentes
O MetaMask é gratuito para usar?
O que acontece se eu perder minha frase semente?
Posso usar o MetaMask em vários dispositivos?
O MetaMask suporta Bitcoin?
Como me proteger de golpes de phishing?
O que são taxas de gás e por que elas mudam?
Continuar aprendendo
Explore mais guias para aprofundar seu conhecimento em cripto.
O que são taxas de gás?
Entenda como funcionam as taxas de gás do Ethereum, por que elas flutuam e como economizar dinheiro em cada transação.
Ler GuiaO que é APY em cripto?
Aprenda como funciona o rendimento percentual anual no DeFi, a diferença entre APY e APR e como a capitalização aumenta seus retornos.
Ler GuiaComo Transferir Cripto
Guia passo a passo para mover tokens entre Ethereum, Arbitrum, Base e outras cadeias de forma segura e econômica.
Ler GuiaColoque seu MetaMask em ação
Agora que sua MetaMask está configurada, ganhe 7,50% APY em USDC com a Poupança em Dólar da Coinstancy. Os juros acumulam a cada segundo e são reinvestidos automaticamente. Sem bloqueio, saque a qualquer momento.
Comece a ganhar na CoinstancyFontes e leitura adicional
Os números e as afirmações nesta página baseiam-se nos documentos abaixo. Os números sensíveis ao tempo (taxas, rendimentos, comissões, dados de mercado) mudam: verifique o valor atual na fonte antes de agir com base nele.
- MetaMask, official download pagemetamask.io
The only place to start an install: links to the official extension stores and app stores.
- MetaMask Supportsupport.metamask.io
Getting started, the Secret Recovery Phrase, adding networks, sending tokens, hardware wallet pairing, editing approvals and the current list of supported networks.
- Ethereum.org, Walletsethereum.org
What a self-custodial wallet is, how private keys and recovery phrases work, and how to choose a wallet.
- Ethereum.org, Gas and feesethereum.org
How gas works, why fees change with demand, and how to read a fee estimate.
- Ethereum.org, Camada 2ethereum.org
Why Layer 2 networks such as Arbitrum, Base and Optimism charge lower fees than Ethereum mainnet.
- Ethereum.org, Security and scam preventionethereum.org
Seed phrase handling, phishing patterns and checks before signing.
- Chainlistchainlist.org
Directory of EVM network parameters (chain ID, RPC, currency symbol) that can be added to MetaMask in one click.
Última revisão: setembro de 2026. Os links externos abrem em uma nova aba; a Coinstancy não é responsável pelo seu conteúdo.
Sua carteira está pronta. Comece a ganhar.
Ganhe 7,50% APY em USDC com a Poupança em Dólar da Coinstancy. Os juros acumulam a cada segundo e são reinvestidos automaticamente, e você pode sacar a qualquer momento.