How to Read a Block Explorer

A block explorer is a free, read-only website for looking up any Bitcoin transaction, block or address in the public ledger. This guide shows how to read inputs, outputs, fees and confirmations, how to check a claim instead of trusting a screenshot, and what an explorer cannot tell you.

Category: Security and Scam Prevention · Published 2026-10-28

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A public window into Bitcoin's ledger

A block explorer is a free website that lets anyone look inside a public blockchain. Bitcoin's ledger is open by design: every transaction is announced publicly, and every full node downloads and checks every block for itself.¹⁷ An explorer is simply a friendly reading room for that ledger, a search engine for the chain.

You do not log in, create an account, or connect a wallet to browse one. It is read-only. You type in a code (a transaction, a block, or an address) and the explorer shows you what the public record says. Nothing you look up is a secret, and looking cannot move any coins. An explorer never needs your private keys or recovery phrase, and any site that asks for them to "check your balance" is a scam; how to protect a recovery phrase explains why.

The three things you can look up

Almost everything on a block explorer falls into three categories, each with its own kind of code:

Transactions, identified by a long transaction ID (a TXID), which is a hash of the transaction itself.³ This shows a single movement of coins: where they came from and where they went.
Blocks, identified by a number (the block height) or by the long hash of the block's header. A block is a batch of transactions confirmed together, roughly every ten minutes on average. Its first entry is the coinbase transaction, which pays the miner the block reward: the block subsidy plus the fees of every transaction in the block.² The subsidy has been 3.125 BTC per block since the April 2024 halving, and it halves every 210,000 blocks, roughly every four years.⁵ The coinbase transaction has nothing to do with the company named Coinbase.
Addresses, the string someone shares to receive coins. Search one and the explorer adds up its balance and lists its full history of activity.

Paste any of these codes into the search box and the explorer looks it up. That is the whole trick.

How to read a transaction

Open a transaction and most explorers show two columns: inputs on one side, outputs on the other. Inputs are the coins being spent, funds that arrived in earlier transactions. Outputs are where those coins are going now.³ Think of it like paying with cash: you hand over whole notes (inputs) and receive change back (an output returning to you).

A few things are worth noticing:

Change is normal. Coins have to be spent whole, so most transactions include an output that sends the surplus back to the sender.³ That is change, not a second payment, and it is why a transaction's total can look larger than the amount actually sent.
The fee is the inputs minus the outputs, the difference kept by the miner who confirms the transaction.² Explorers show it separately.
The TXID is the transaction's fingerprint, a code you can share or re-check later. The time shown for a confirmed transaction is normally the timestamp of its block, which the miner sets: it must be later than the median of the previous 11 blocks and no more than two hours ahead, so treat it as approximate.⁴

What confirmations actually mean

The number of confirmations tells you how deeply settled a transaction is. When you first send coins, the transaction sits in a waiting area called the mempool with zero confirmations: broadcast, but not yet in a block. Once a miner includes it in a block, it has one confirmation. Every new block stacked on top adds another.⁶

Picture wet concrete: the deeper your transaction is buried under later blocks, the harder it becomes to dig back out and reverse. One confirmation sharply cuts the risk, though the newest block is occasionally replaced by accident. For high-value payments the Bitcoin developer guide suggests waiting for at least six, a number it calls somewhat arbitrary: a convention, not a law.⁶ And remember: confirmed means recorded, not honest. The blockchain proves a payment happened; it cannot promise the deal behind it was fair.

Verify it yourself — don't trust the screenshot

This is the real superpower of a block explorer. A screenshot of a payment, a balance, or a "proof of funds" can be faked in seconds with an image editor. A TXID or address is different: it is a lookup code that points to the shared public record. Anyone, anywhere, can paste it into an explorer and see whether the claim is true.

So when someone shows you a picture, ask for the TXID or address and check it yourself. Does the transaction exist? Does the amount match? How many confirmations does it have? For extra assurance, cross-check on a second explorer, since each one is a website run by someone who could be wrong or offline. The gold standard is running your own Bitcoin node, which downloads and checks every block itself instead of relying on anyone else's copy.⁷ The same check works for mining claims: a block's height or hash leads to its coinbase transaction, which shows the reward the block paid and the addresses that received it.² How to verify cryptocurrency claims covers more of these checks.

The honest limits of a block explorer

Explorers are powerful, but they are not magic. Keep their limits in mind:

Pseudonymous, not anonymous. An address is not your name, but every transaction it touches is public for good.¹ Share your address and you share its whole history.
It cannot name owners. The chain records amounts and addresses, never real-world identities or intentions.¹ Any claim linking a person to an address comes from off-chain, and may be wrong.
You trust the operator's copy. A single explorer shows one website's view of the chain, and its operator can see which addresses and transactions you look up. Cross-checking, or running your own node, removes that trust.

Used with these caveats, a block explorer turns "trust me" into "check for yourself", which is the whole point of an open ledger. Is Bitcoin anonymous? goes further into privacy.

FAQ

Do I need an account or wallet to use a block explorer?

No. Block explorers are read-only public websites: there is no sign-up, and you never connect a wallet or enter a private key or recovery phrase. You simply paste in a transaction ID, block, or address to look it up. Any explorer that asks for your seed phrase to show your balance is a scam.

Is it safe to search my own Bitcoin address?

Looking it up cannot move your coins and reveals nothing about your keys. Two things are worth knowing. Anyone you give the address to can see its full balance and history, because Bitcoin addresses are pseudonymous, not anonymous. And the explorer's operator can see which addresses you search for; running your own node avoids that.

How many confirmations should I wait for?

It depends on how much is at stake, since more confirmations make a transaction harder to reverse. Many people treat one as enough for small everyday amounts, while the Bitcoin developer guide suggests at least six for high-value payments, a convention rather than a fixed rule. Keep in mind that confirmed only means the payment was recorded, not that the deal was honest.

Why is my transaction stuck as unconfirmed?

An unconfirmed transaction is sitting in the mempool, the waiting area for transactions not yet placed in a block. If the fee attached was low relative to demand, miners may include it later, so it can take longer to confirm. It is not lost, and you can watch its status on any explorer.

Can a block explorer tell me who owns an address?

No. Explorers show on-chain activity, meaning amounts, addresses and timing, but never real-world identities. Any claim that a specific person controls an address comes from outside the blockchain and could be mistaken or simply made up.

Key takeaways

A block explorer is a read-only window into Bitcoin's public ledger, and it never needs your keys or recovery phrase.
A transaction's fee is its inputs minus its outputs, and an output going back to the sender is usually change.
Confirmations count the blocks on top of a transaction: more of them make it harder to reverse, but confirmed only means recorded.
Ask for a TXID or address and check it yourself instead of trusting a screenshot, ideally on a second explorer or your own node.
Addresses are pseudonymous: an explorer shows amounts and history, never who owns them.

Sources

Bitcoin: A Peer-to-Peer Electronic Cash System (the whitepaper), section 10 (Privacy): all transactions are announced publicly, and the public can see amounts moving without information linking them to anyone — bitcoin.org
Bitcoin Developer Guide, Block Chain: blocks referred to by height or by header hash, about ten minutes per block (2,016 blocks in two weeks), the coinbase transaction as the first transaction collecting the block subsidy plus fees, and the fee as inputs minus outputs — Bitcoin Project (developer.bitcoin.org)
Bitcoin Developer Guide, Transactions: inputs and outputs, the transaction identifier (txid) as the transaction's hash, and change outputs returning the surplus to the spender — Bitcoin Project (developer.bitcoin.org)
Bitcoin Developer Reference, Block Chain (block headers): the block time is set by the miner, must be later than the median of the previous 11 blocks, and full nodes reject headers more than two hours in the future — Bitcoin Project (developer.bitcoin.org)
Controlled supply: the block subsidy halves every 210,000 blocks (about four years); block 840,000 was reached on 2024-04-20, starting the 3.125 BTC era — Bitcoin Wiki
Bitcoin Developer Guide, Payment Processing (Verifying Payment): what 0, 1, 2 and 6 confirmations mean; the newest block is sometimes replaced by accident; at least six confirmations, a somewhat arbitrary number, for high-value payments — Bitcoin Project (developer.bitcoin.org)
Bitcoin Developer Guide, Operating Modes: a full node downloads and validates every block from the genesis block to the latest, so it does not rely on anyone else's copy of the chain — Bitcoin Project (developer.bitcoin.org)

Some specific claims in this article are scheduled for further source review; citations may be expanded (see our editorial policy).