Why ERC‑20 Transfers, NFTs, and ETH Transactions Still Confuse People (and How to Actually Track Them)

Okay, so check this out—on any given Tuesday I’ll poke around transaction histories and still spot somethin’ that makes me go, Whoa! Really? A token moved but the ETH balance didn’t budge. Hmm…

Short answer: that’s normal. Longer answer: there are a few layers to peel back before things make sense. I’ll be blunt—blockchains are straightforward in one sense (every change is recorded), and maddeningly opaque in another (you need the right lens to read the record).

My instinct when I first stared at raw logs was: this is useless. Actually, wait—let me rephrase that: it felt useless until I learned to read the logs and events like a detective reads fingerprints. On one hand the UI shows a friendly “transfer” badge. On the other hand the actual gas, internal ops, and event topics tell a different story. And, yeah, that part bugs me.

Here’s the practical map for anyone tracking ERC‑20 tokens, NFTs, or ETH transactions: know what to look for (transactions vs internal transactions vs logs), where to look (block explorers and contract pages), and how to interpret the signals (approve vs transfer, token decimals, metadata pointers).

How to read a transfer without losing your mind

Start simple. Transactions change state. Period. But what state? Wallet ETH balance, token balances tracked by a contract, or off‑chain pointer values for NFT metadata? All of the above are possible. When a wallet sends 0.01 ETH, you’ll see a plain value on-chain. When a wallet moves an ERC‑20 token, you’ll often see a 0 ETH transfer accompanied by logs from the token contract. If you only watch ETH, you’ll miss token movements.

Check the transaction receipt. Look for Transfer events. Seriously? Yes—most ERC‑20 transfers emit a Transfer(address,address,uint256) event, and that’s your smoking gun. The explorer UI usually surfaces it, but if you dig into logs you’ll find the indexed topics: from, to, and the value (which you then scale by the token’s decimals).

Important nuance: approvals are different from transfers. An approve() call sets an allowance. A later transferFrom() call actually moves tokens. On one occasion I chased a “missing” token and discovered someone had only approved, not transferred. My initial panic turned into an “aha” once I saw the allowance event. Lesson: don’t confuse approve with transfer.

Using an ethereum explorer the right way

If you want to follow the breadcrumbs, use an ethereum explorer that surfaces contract source, ABI, decoded logs, and internal transactions. I like to link straight to a reliable explorer when I’m sharing proof with teammates—makes the debate shorter. For quick dives, try the ethereum explorer as a starting point.

When you land on a transaction page, here’s my checklist:

• Is the value field nonzero? If yes, ETH moved.
• Are there Transfer logs? If yes, tokens moved (check decimals).
• Do internal transactions exist? Those are contract-to-contract moves.
• Was gas used fully? Reverts show gas burned and returned state—useful to see failed attempts.
• Is the contract verified? If yes, you can inspect source and function names—huge time-saver.

Also: mempool replacement and nonces. If you send a transaction that’s stuck, you can bump or replace it by resubmitting with the same nonce and higher gas. On one project, I had to do that for five transactions in a row—very very annoying, and I learned to watch nonces like a hawk.

NFTs: ownership is simple, metadata is not

NFT ownership is typically tracked on-chain by ERC‑721 or ERC‑1155 contract state (ownerOf, balanceOf). Still, the human-facing art and metadata often live off-chain. So you might own the token but the image is served from IPFS, a CDN, or a web server. If that server goes down or the URL changes, your token’s “look” can change even though ownership stays the same. Weird, right? It’s why on-chain metadata or IPFS hashes are preferred by collectors.

When tracking NFTs, check events for Transfer and Approval as with ERC‑20s. Also inspect tokenURI calls (if available) to see metadata endpoints. If you’re integrating an app, cache metadata and verify CIDs so you’re not broken every time a centralized host has downtime.

Common pitfalls and how to avoid them

One common trap: decimal misreads. Tokens often report balances in the smallest unit (wei-like), and you must divide by 10^decimals. I’ve seen dashboards report 1e18 tokens because someone forgot to scale. Another is fake tokens—contracts with identical names and symbols. Always check contract address, not just the label.

Gas estimation errors are another headache. Complex contracts with loops or heavy storage ops may under‑estimate gas; users then see “out of gas” fails. If you’re a developer, set conservative gas limits and surface clear fallbacks in your UI.

Security note: token approvals are a common attack vector. Approving unlimited spend for a random dApp can let an attacker drain your token balance if the dApp is malicious or compromised. I’m biased, but I prefer approving minimal allowances and re‑approving when needed—even if it costs more in fees. Safer, imo.

Developer checklist: instrumenting observability

If you run a dApp or a token contract, embed events liberally. Emit contextual events for important state changes beyond Transfer and Approval. Consumers of your contract (wallets, indexers) will thank you. Use verified source code on explorers and document your ABI. If you expect large airdrops or high throughput, provide a public endpoint or webhook so people and indexers can subscribe to events instead of scraping pages.