MetaMask Extension® | Browser Wallet for Ethereum & Web3

Overview

The MetaMask extension is a browser-based crypto wallet that lets you manage Ethereum, ERC-20 tokens, NFTs, and connect to thousands of decentralized applications (dApps). It runs as an extension in Chrome, Firefox, Edge, Brave, and other Chromium-based browsers. MetaMask is a non-custodial wallet — you control your private keys and your recovery phrase.

Official sources: Always install MetaMask from the official website (metamask.io) or your browser's official extension store (Chrome Web Store, Firefox Add-ons, etc.). Avoid third-party copies or unofficial download links.

Key Features

Self-Custody: Full control of private keys and seed phrase; MetaMask does not hold funds for you.
dApp Connectivity: Seamlessly connect to DeFi platforms, NFT marketplaces, games, and other Web3 apps.
Multi-Network Support: Use Ethereum mainnet, testnets, and add custom networks (Polygon, BSC, Optimism, Arbitrum, etc.).
Token Management: View and add ERC-20/ERC-721 tokens manually or automatically.
Transaction Signing: Sign transactions and messages locally within the extension.
Import & Restore: Create a new wallet or import an existing one with a 12-word or 24-word seed phrase.
Browser Integration: Works directly in-browser with wallet selectors on dApp websites for smooth connectivity.

How to Install MetaMask Extension

Go to the official site: metamask.io and click the browser extension link, or visit the Chrome Web Store / Firefox Add-ons page.
Click Add to Chrome (or the equivalent “Add to Browser”) and confirm installation.
Pin the extension to your toolbar for easy access.
Open MetaMask, choose Create a Wallet or Import Wallet, and follow the on-screen steps.
Write down your secret recovery phrase and store it offline in a safe place — never share it.

Security Best Practices

Only install MetaMask from metamask.io or official browser stores.
Never share your secret recovery phrase with anyone; MetaMask support will never ask for it.
Store your recovery phrase offline (paper or metal backup), not in screenshots or cloud storage.
Verify the URL and site before connecting MetaMask to any dApp. Confirm transaction details on the extension popup.
Use a hardware wallet (Ledger, Trezor) with MetaMask for extra security when approving high-value transactions.
Keep your browser, OS, and MetaMask extension up to date to receive security patches.

Troubleshooting

Extension not appearing

Check your browser's extension manager and ensure MetaMask is enabled and pinned.
Restart your browser and try reinstalling from the official store if needed.

Cannot connect to dApp

Ensure the correct account is selected in MetaMask and the network matches the dApp (e.g., Ethereum mainnet vs. Polygon).
Refresh the dApp page and click the site's connect button again.
Disable conflicting wallet extensions temporarily (e.g., other Web3 wallets) which may cause conflicts.

Missing tokens or NFTs

Manually import token contract addresses into MetaMask or use the token tracker on explorers like Etherscan to find contract details. For NFTs, add the network and view under the NFTs tab or use a dedicated NFT viewer.

Advanced Tips

Use custom RPC endpoints to connect to alternative networks or private nodes.
Set custom gas prices for faster or cheaper transactions depending on network congestion.
Pair MetaMask with Ledger or Trezor to require hardware confirmations for signing transactions.

Phishing warning: Beware of fake MetaMask sites and malicious extensions. Never enter your seed phrase on any website. If prompted to reveal your seed to recover funds, it is a scam.

FAQ

Is MetaMask free?

Yes — the MetaMask extension is free to install and use. Network fees (gas) apply for blockchain transactions and DApp interactions.

Can I use MetaMask on mobile?

Yes — MetaMask offers a mobile app for iOS and Android with similar wallet features and dApp browser functionality.

How do I restore my MetaMask wallet?

Install the MetaMask extension, click Import Wallet, and enter your secret recovery phrase exactly as saved. After import, your accounts and balances will be available (depending on network).

Does MetaMask support other blockchains?

MetaMask is Ethereum-focused but supports many EVM-compatible networks (Polygon, BSC, Avalanche, etc.) via custom RPC. Native Bitcoin support is not available by default.

Conclusion

The MetaMask extension is a powerful gateway to Web3 — letting you manage tokens, NFTs, and interact with decentralized applications directly from your browser. Install only from official sources, protect your recovery phrase, and consider hardware wallet integration for maximum security.