Query Bitcoin UTXOs
Bitcoin has no account balances — you work with unspent outputs. Use standard Bitcoin Core RPC methods against our btc endpoint to inspect UTXOs and transactions. The calls are unchanged; you just swap the base URL and add a Bearer header.
- An API key (sk_live_...) with read access.
- A Bitcoin txid, and the output index (vout) you want to inspect.
1Check a specific UTXO with gettxout
POST gettxout to /v1/rpc/btc with the txid and vout. If the output is unspent you get its value and scriptPubKey; if spent, the result is null.
curl https://api.1st-node.com/v1/rpc/btc \
-H "Authorization: Bearer sk_live_..." \
-d '{"method":"gettxout","params":["4a5e...9c2f",0]}'2Read the UTXO result
value is in BTC and scriptPubKey describes the spending condition. A null result means the output has already been spent.
> {
> "value": 0.0425,
> "confirmations": 812,
> "scriptPubKey": { "type": "witness_v0_keyhash", "address": "bc1q..." }
> }3Fetch the full transaction
Use getrawtransaction with the verbose flag to get decoded inputs and outputs, so you can enumerate every vout of a transaction.
curl https://api.1st-node.com/v1/rpc/btc \
-H "Authorization: Bearer sk_live_..." \
-d '{"method":"getrawtransaction","params":["4a5e...9c2f",true]}'Frequently asked
Are these standard Bitcoin Core methods?
Yes. gettxout, getrawtransaction and getblock are the standard Bitcoin Core RPC methods. Point them at /v1/rpc/btc with a Bearer header — no node to run.
How do I get all UTXOs for an address?
Bitcoin Core is transaction-indexed, not address-indexed. Enumerate outputs from an address's transactions, or use archive-depth history served from our own nodes.
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