Base Wallet Tracker

Follow any address on Base, Coinbase's Ethereum L2, and get its on-chain life in clean JSON. Drop in one or many wallets, pick what you want to see — what it holds, what it's been doing, or what tokens have moved through it — and this Actor hands you back a flat, schema-stable dataset you can store, diff, alert on, or feed straight into an agent. No API key, no RPC node, no archive-node bill, no web scraping.

It reads from Blockscout, the open-source explorer that indexes Base. Blockscout is the same data you see when you paste an address into a block explorer — except here it arrives as machine-readable records with raw and human-readable balances already worked out for you, ready for a spreadsheet, a database, or a model's context window.

Why Base, and why an explorer instead of an RPC node

If you only have an RPC endpoint, "what ERC-20s does this wallet hold?" is a genuinely annoying question. There's no single call for it — you'd have to know every token contract in advance and poll each balanceOf. Transaction history over RPC means walking blocks. An indexer like Blockscout has already done that work: holdings, history, and transfers are one HTTP GET each. This Actor wraps those calls, normalizes the messy nested JSON into flat rows, converts every raw integer balance into a real decimal using the token's own decimals, and stops cleanly at your maxResults.

Base specifically because it's where a huge slice of new on-chain activity now lives — low fees, fast blocks, a direct Coinbase on-ramp — which makes wallet-level tracking (whales, treasuries, your own positions) actually worth doing here.

The three modes

You choose one mode per run. Every wallet in addresses is fetched in that mode.

Mode	Endpoint	One record =
holdings (default)	/addresses/{addr}/tokens?type=ERC-20	One ERC-20 the wallet currently holds, with a human-readable balance.
transactions	/addresses/{addr}/transactions	One on-chain transaction (native ETH transfer or contract call), with value, fee, method, and status.
token-transfers	/addresses/{addr}/token-transfers	One ERC-20 transfer in or out of the wallet, with the human-readable amount and counterparties.

Pagination is handled for you: the Actor follows Blockscout's next_page_params cursor and keeps pulling pages only until the combined maxResults cap is reached.

Input

{
  "addresses": ["0xd8da6bf26964af9d7eed9e03e53415d37aa96045"],
  "mode": "holdings",
  "maxResults": 15
}

Field	Required	Default	Notes
addresses	yes	—	Array of Base wallet addresses (0x…). EOAs or contracts. The prefill is vitalik.eth on Base.
mode	no	holdings	holdings, transactions, or token-transfers.
maxResults	no	50	Hard cap on total records across all wallets (1–1000). Prefilled at 15 for a quick QA run.

Output by mode

holdings — one row per token:

{
  "address": "0xd8da6bf26964af9d7eed9e03e53415d37aa96045",
  "tokenSymbol": "USDC",
  "tokenName": "USD Coin",
  "tokenAddress": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
  "balance": 1532.94,
  "rawBalance": "1532940000",
  "decimals": 6,
  "tokenType": "ERC-20"
}

transactions — one row per transaction:

{
  "address": "0xd8da6bf26964af9d7eed9e03e53415d37aa96045",
  "hash": "0x6f047c2ea51bffe8684ba17e50f9220f42a209bac5823b924275dd3281a4865c",
  "from": "0x704C6b7C67E2da327f566cfd9085F9bBd9e1be31",
  "to": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045",
  "valueEth": 0,
  "method": "transfer",
  "status": "ok",
  "timestamp": "2026-06-30T14:24:51.000Z",
  "blockNumber": 48020072,
  "feeEth": 0.000000132414297468
}

token-transfers — one row per ERC-20 movement:

{
  "address": "0xd8da6bf26964af9d7eed9e03e53415d37aa96045",
  "hash": "0x398c3bc85d4153f582b448d7f64a78b215320a558230245663bf4ba6203dd9ec",
  "tokenSymbol": "USDC",
  "tokenAddress": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
  "from": "0xFFA170101E057a878A75531EC194feB350500cC4",
  "to": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045",
  "amount": 0.15,
  "timestamp": "2026-06-30T14:01:37.000Z"
}

Field reference

Field	Appears in	Meaning
address	all	The wallet you tracked (echoed on every row so multi-wallet datasets stay groupable).
tokenSymbol / tokenName / tokenAddress	holdings, transfers	The ERC-20 in question and its Base contract.
balance / rawBalance / decimals	holdings	balance is human-readable (rawBalance ÷ 10^decimals); rawBalance is the on-chain integer; decimals is the token's precision.
tokenType	holdings	Token standard (always ERC-20 here).
hash	transactions, transfers	Transaction hash — paste into any Base explorer to inspect.
from / to	transactions, transfers	Counterparties. In transfers, compare against address to tell inflow from outflow.
valueEth	transactions	Native ETH moved, already in ETH (not wei).
method	transactions	Decoded function name when Blockscout knows it (e.g. transfer, swap), else null.
status	transactions	ok for success, error for a reverted/failed tx.
feeEth	transactions	Gas fee actually paid, in ETH.
amount	transfers	Tokens moved, human-readable.
timestamp / blockNumber	varies	ISO-8601 time and block height.

A table view ships with the Actor, so the dataset is readable at a glance and trivially consumable by an LLM.

Real use cases

• Whale & smart-money tracking. Feed a list of known whale or fund addresses, run token-transfers on a schedule, and watch what they accumulate or dump on Base before it shows up elsewhere.
• Portfolio & treasury monitoring. Run holdings over your own or a DAO's wallets to snapshot balances into a sheet or database — a poor-man's portfolio tracker with zero third-party custody.
• Forensics & flow tracing. Pull transactions + token-transfers for a suspicious address and follow the from/to graph to map where funds came from and went.
• A wallet tool for AI agents. The flat output makes this a clean "look up this Base wallet" function for an LLM or autonomous agent — ask it "what does 0x… hold and what did it just move?" and the agent calls this Actor instead of parsing explorer HTML.
• Accounting & tax exports. Export transactions/token-transfers to CSV and hand them to your bookkeeping flow as a dated activity log.

FAQ

Do I need a Blockscout or Base API key? No. The public Blockscout Base API is keyless. You just need an Apify account to run the Actor.

Why a real browser User-Agent under the hood? Blockscout's edge rejects requests that look like bots with HTTP 403. The Actor always sends a genuine desktop Chrome User-Agent plus Accept: application/json, so every call goes through — you never have to think about it.

What about rate limits? Calls are spaced ~250 ms apart and the Actor automatically backs off and retries on HTTP 429 / 5xx. Keep maxResults modest if you run very frequently.

Does it handle balances with weird decimals correctly? Yes. Each balance is divided by the token's own decimals using big-integer math, so a 6-decimal USDC and an 18-decimal memecoin both come out as correct human-readable numbers — and the untouched rawBalance is kept for precision-critical work.

Can I track several wallets at once? Yes — pass as many addresses as you like. maxResults is a global cap across all of them, filled wallet by wallet.

Is it agent / x402 friendly? Very. No auth, no browser step, no login — just deterministic structured output with a table view. That makes it an ideal tool to expose to an autonomous agent or wire into a pay-per-call (x402-style) workflow.

Automate it

Set a schedule in Apify — hourly, every few minutes, daily — and point the dataset at a webhook, Google Sheet, or your own service. Run holdings nightly for portfolio snapshots, or token-transfers on a tight loop for live whale alerts, and you've got a self-maintaining Base wallet-intelligence feed with no node and no infrastructure to babysit.

---

Data sourced from the public Blockscout Base API. This Actor is not affiliated with Blockscout, Coinbase, or Base. Nothing here is financial advice — on-chain data is informational only.