Is Etherscan owned by Ethereum Foundation?

No, Etherscan is an independent Singapore-based company. The Ethereum Foundation has no involvement. Etherscan is the most popular but not the only explorer — alternatives include Ethplorer, Beaconcha.in, and Blockscout-based explorers.

Does Etherscan store my wallet info if I connect it?

Connecting via WalletConnect or MetaMask only reads on-chain data. Etherscan doesn't get private keys or sign transactions. The 'Sign in' feature (optional) lets you customize labels and is local to your account.

How often should I revoke token approvals?

Quarterly minimum. After any compromise (you clicked a suspicious link, your seed phrase was exposed) immediately. Power users do it monthly via revoke.cash or Rabby's built-in tool.

What's a 'failed transaction' but I still paid gas?

Gas pays for computation regardless of outcome. A failed transaction still consumed gas to verify the failure. Common when you set slippage too low and price moved before your trade executed — you paid $20 gas to revert.

Can I run my own Etherscan?

No, the indexing infrastructure is proprietary. The open-source alternative is Blockscout (run by Web3 Labs), self-hostable. Most users have no reason to run their own.

What's the green checkmark on a contract?

Source code verified — the project published the Solidity source matching the deployed bytecode. Lets anyone audit. Unverified contracts (no source) require trusting the deployer blindly.

Can I see ENS names on Etherscan?

Yes — addresses with associated ENS names (vitalik.eth) show both the address and the ENS. You can paste an ENS into the search bar instead of the full address.

Does Etherscan show my private key or balance privately?

Etherscan only shows public on-chain data — your wallet balance, your transaction history. Anyone with your address can see this; that's how Ethereum works. Your private key is never on-chain.

Etherscan Tutorial For Beginners 2026

What is Etherscan and what does it do?

Etherscan launched in 2015 as a frontend for Ethereum's blockchain — letting humans browse the public ledger without running a node. Today it indexes every block, transaction, contract, and event on the Ethereum mainnet, plus several testnets. Sister sites cover other EVM chains: BscScan (BNB Chain), Polygonscan (Polygon), Arbiscan (Arbitrum), Optimistic Etherscan (Optimism), Basescan (Base) — same interface, different chains.

All block explorers are free to use. They don't custody anything — they only read on-chain data and present it. Even if Etherscan went offline tomorrow, the underlying blockchain data wouldn't change.

How to look up a transaction on Etherscan

Most common use case — your swap got stuck and you want to know why.

Copy the transaction hash from your wallet (MetaMask → Activity → click pending → 'View on Etherscan'). It looks like 0xabc123...
Paste into Etherscan's search bar at etherscan.io.
Read the top section: Status (Success / Pending / Failed), Block number, Timestamp, From/To addresses, Value (ETH sent), Transaction Fee (gas paid).
If Status is 'Failed', click the 'Click to see More' button. Etherscan shows the revert reason — common ones: 'insufficient allowance', 'slippage too low', 'pool empty', 'contract paused'.
If Status is 'Pending' and it's been more than 10 minutes, your gas fee was too low. You can speed up by submitting a replacement transaction with higher gas (MetaMask → Activity → Speed up).

How to look up a wallet address

Paste any Ethereum address into Etherscan's search. The wallet page shows: current ETH balance, total transaction count, current ERC-20 token holdings, NFT holdings, and full transaction history. Below, tabs for Transactions / Internal Transactions / ERC-20 Token Txns / ERC-721 NFT Txns let you filter the activity.

Use cases: confirm your own wallet activity, check a counterparty's history before sending them funds, investigate a suspicious wallet that received funds you didn't recognize. Pro tip: 'Etherscan label' tag shows known wallet identities (e.g. Vitalik's main wallet, exchange hot wallets, known scammers).

Token Approval Checker — the most important Etherscan feature

Every time you click 'Approve' on a DApp (Uniswap, OpenSea, any DeFi protocol), you grant that contract permission to spend a specific token from your wallet. These approvals are persistent — they don't expire. Old approvals from compromised or malicious sites are the #1 cause of wallet drainage in 2026.

Etherscan's Token Approval Checker at etherscan.io/tokenapprovalchecker lets you see and revoke all approvals on your wallet. Connect MetaMask (read-only — it doesn't access funds). Etherscan shows: which contract has approval, for which token, with what spending limit (often 'Unlimited').

Go to etherscan.io/tokenapprovalchecker.
Paste your wallet address (no need to connect — read-only).
Etherscan lists all active approvals. Sort by 'Allowance' descending — 'Unlimited' approvals are highest risk.
For each approval, decide: do you still use this contract? Old approvals from 'free NFT mint' or 'connect to claim airdrop' should be revoked.
Click 'Revoke' next to risky approvals. Connect MetaMask, pay ~$2-5 in gas per revoke. Worth it.
Alternative: revoke.cash and rabby.io have cleaner interfaces for the same task. Whichever you use, do this quarterly.

How to verify a smart contract on Etherscan

Before buying a new token, you should verify the contract's identity. Two checks: (1) the contract's source code is published and matches what's deployed; (2) the contract behavior matches what the project claims.

On a token's contract page (e.g. etherscan.io/token/0x...), look for the 'Contract' tab. A green checkmark with 'Verified' means the source code is published. Click to read the actual Solidity code. Most beginners can't audit code line-by-line, but the existence of verified code is itself a positive signal. Unverified contracts (compiled binary only, no source) are higher risk.

Etherscan gas tracker — when to buy and sell

Gas fees on Ethereum fluctuate wildly based on network demand. Etherscan's Gas Tracker (etherscan.io/gastracker) shows current gas in Gwei plus historical trends. Low gas (under 20 Gwei) means your transactions cost $1-3. High gas (over 100 Gwei) means your transactions cost $20-50+.

For non-urgent transactions, check gas tracker first. Patterns: gas is usually lower on weekends and overnight US-time. New NFT drops or token launches spike gas — wait if you can.

Other block explorers — same skills, different chains

Once you know Etherscan, the EVM family is mostly identical:

bscscan.com — BNB Smart Chain
polygonscan.com — Polygon
arbiscan.io — Arbitrum
optimistic.etherscan.io — Optimism
basescan.org — Base
snowtrace.io — Avalanche
ftmscan.com — Fantom

Non-EVM block explorers

Solana, Bitcoin, and other non-EVM chains use different explorers but conceptually similar. Solscan (solscan.io) and SolanaFM (solana.fm) cover Solana. Mempool.space and Blockstream Explorer cover Bitcoin. Tronscan.org covers Tron. The 'paste hash to see transaction' workflow is universal.

Etherscan Tutorial For Beginners — How To Read Ethereum Transactions 2026