Deciphr Academy
Track 2 · Module 11 · Lesson 7 of 7 · 7 min read

How do you check that a crypto payment someone says they sent really arrived?

Short answer

Look up the hash on the right chain's explorer, then check the status, the receiving address, the token contract and the amount, each in full.1,2 An explorer shows what the chain recorded. It can't prove who owns an address, say why money was sent, or reverse a payment.3,4,5

The chain showsIt doesn't showThe hash is in a blockIt succeededWhich contract wrote the logFrom, to and amountIt can't be pulled backWho owns an addressWhat it was forWhat a token is worthWhether a label is true
Fig. 7. What the chain can show, and what it can't. The left side is evidence. The right side needs other proof.

A claim is not a payment

Brackenlow Design says: "Refund sent." It gives Maya a transaction hash. That is a claim. The explorer is where she checks it.6

Etherscan describes this as exactly what explorers are for: looking up and confirming transactions.6 It also says it has no control over transactions, so it can only report what happened.6

Maya's checklist

  1. The right chain. The refund is on Ethereum, so she uses an Ethereum explorer. An explorer only shows the chains it covers.7
  2. The hash. She pastes in the whole hash. If it shows as pending, the money has not arrived yet.8 If it was dropped and never sent again, it is as if it never happened.9
  3. The status. It must say success. A failed transaction moved nothing, even though it charged a fee.10,11
  4. The confirmations. The more blocks on top, the safer it is to rely on.1
  5. The receiver. The token transfer must go to Brindlecove's full address, checked character by character, not just the start and end.12
  6. The token. The Transfer log must come from the contract address the issuer publishes.10,2
  7. The amount. Raw number ÷ 10^decimals.13
  8. The sender. The from address should match the one Brackenlow gave in its signed invoice. The chain itself only knows addresses.14
  9. A second look. For anything important, compare with another source, such as a second explorer.12,15

When the hash changes

A pending payment can be sped up or cancelled by sending a new transaction with the same nonce. Module 5 explains how.9 When that happens, the new transaction replaces the old one, and the old hash shows as dropped and replaced.9

So a "dropped" hash does not always mean no money moved. Ask the sender for the hash of the replacement, and check that one.9

What Maya can conclude

Finding Why she can rely on it
A transaction with this hash is in block 41,618,240, and it succeeded. The receipt's status is success, and blocks have been added on top.10,1
The real Quellwick Dollar contract recorded 3,000 tokens moving to Brindlecove's address. The Transfer log's address matches the issuer's published contract, and its data is 3,000,000,000 at 6 decimals.10,2,13
The tokens came from the address on Brackenlow's invoice. The log's from address matches it in full.4
Brindlecove paid no fee for this. The fee is paid by the sender, here Brackenlow's address.14
The payment can't be pulled back. Successful transactions are irreversible. Only the holder of the tokens can send them back.5

What Maya cannot conclude

Question Why the explorer can't answer it
Who really controls the sending address? The chain records addresses, not owners. Name tags come from the explorer, and can be wrong.14,3
What the payment was for? A Transfer event holds only from, to and value. The invoice it settles is not on the chain.4
Is a Quellwick Dollar worth $1? That depends on its issuer, which Module 22 covers. Etherscan only shows a price for tokens listed on a price site.16
Is the explorer itself right? An explorer is one company's copy of the chain. Etherscan offers EthValidate to check balances and statuses against other nodes. Check important results elsewhere.15
Our viewAn explorer turns "trust me" into "check for yourself", but only for what the chain records. Who someone is, and why they paid, still needs ordinary paperwork.
Sources
  1. What is a Transaction Hash (Txn hash)?. Etherscan Information Center, 5 December 2019, updated 21 June 2026.
  2. How to identify scam tokens. ethereum.org guide, page updated 6 June 2026.
  3. Public Name Tags, Labels & Public Notes. Etherscan Information Center, 7 February 2021, updated 21 June 2026.
  4. ERC-20: Token Standard. Ethereum Improvement Proposals (Fabian Vogelsteller, Vitalik Buterin), created 19 November 2015, status Final.
  5. How to refund a Transaction?. Etherscan Information Center, 27 November 2019, updated 21 June 2026.
  6. What is a Block Explorer?. Etherscan Information Center, 9 April 2026, updated 4 August 2026.
  7. Mempool FAQ. mempool.space (open-source block explorer).
  8. What is a Pending Transaction?. Etherscan Information Center, 5 December 2019, updated 21 June 2026.
  9. Transaction Dropped & Replaced?. Etherscan Information Center, 5 December 2019, updated 21 June 2026.
  10. JSON-RPC API. ethereum.org developer docs, page updated 28 June 2026.
  11. What are the Reasons for Failed Transactions?. Etherscan Information Center, 5 December 2019, updated 21 June 2026.
  12. Address Poisoning Attacks. Etherscan Information Center, 15 January 2024, updated 21 June 2026.
  13. ERC-20. OpenZeppelin Contracts 5.x documentation.
  14. Transactions. ethereum.org developer docs, page updated 7 October 2026.
  15. EthValidate. Etherscan Information Center, 1 April 2022.
  16. Understanding the Token page. Etherscan Information Center, 25 March 2020, updated 21 June 2026.
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General education built from the publicly available sources listed above. Not financial, legal, tax or investment advice. Naming a company, project or regulator is not an endorsement either way. Last checked 2026-10-22. Terms and disclaimer.