Query the chain · Mempool API

Bitcoin mempool API for unconfirmed transactions and fee estimation

The mempool is where a Bitcoin transaction lives before it is mined, and it is what you read to estimate a fee or watch for an incoming payment. BitcoinDatabase exposes the live mempool over a clean REST API: list unconfirmed transactions, look up a specific txid before it confirms, check an address for pending activity, and pull current fee rates by target confirmation window so you attach the right fee instead of guessing.

Run it without hosting Bitcoin Core, syncing the chain, or hitting the rate limits of a shared public endpoint. The same indexed data, confirmed and unconfirmed, is queryable in SQL and dashboards, so your wallet, payment flow or dashboard reads from one source. Informational on-chain data only, not financial advice.

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REST API · SQL · dashboards · indexed from genesis

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informational on-chain data · not financial advice

REST API · SQL · dashboards, one indexed dataset. Querying the indexed Bitcoin blockchain ...

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Indexed from genesis queryable in seconds

On-chain data not financial advice

Why it works

What you get with mempool api

Live unconfirmed data

List mempool transactions, look up a txid before it confirms, and check any address for pending activity, so you react the moment a payment broadcasts rather than after a block.

Fee estimation built in

Pull current fee rates by target confirmation, from next-block to economy, computed from real mempool state, so your wallet or service attaches a fee that gets mined without overpaying.

No node, no rate wall

Skip running Bitcoin Core and skip the throttling of a shared public mempool endpoint. One API key gives you production access to confirmed and unconfirmed data alike.

What it handles

The indexed Bitcoin chain, queryable your way

Look up an address, a transaction, a UTXO, the rich list or an on-chain metric, by REST API, SQL or dashboard. The same authoritative data, reconciled block-by-block against the canonical chain, without running a node.

List current unconfirmed mempool transactions
Look up a transaction by txid before it confirms
Estimate fees by target confirmation window
Watch an address for incoming pending payments
Query the same data via REST, SQL or dashboards

GET /v1/address/{addr} query result

200 · JSON

{
  "address": "bc1qxy2k…l0wdv8",
  "balance_btc": 68432.10,
  "balance_usd": 4612165420,
  "tx_count": 1284,
  "unspent_outputs": 37,
  "first_seen": "2014-02-09"
}

indexed from genesis · to the satoshi ✓ reconciled block-by-block

Why BitcoinDatabase

One platform, queryable three ways

Not a raw node to sync, not an indexer to build, and not five vendors to stitch together. The fully-indexed Bitcoin blockchain, available as a REST API, as SQL, and as dashboards, on one authoritative dataset.

REST API

Typed JSON for addresses, transactions, balances, UTXOs and metrics. Drop it into apps, wallets, explorers and agents with curl, Python or our SDKs.

SQL access

Run SQL directly against the indexed Bitcoin dataset for ad-hoc analysis, cohorts and exports, the same data the API and dashboards read from.

Compliance-first

Informational on-chain data and analytics only. Entity labels and flow tracing are framed as tooling to support a regulated team's own review, not accusations.

Good questions

Questions about mempool api

It returns live mempool state: the set of unconfirmed transactions, a lookup for any pending txid, pending activity for an address, and current fee-rate estimates by target confirmation window. It reads from our indexed view of the chain, so you get confirmed and unconfirmed data from one endpoint without running a node.

Fee estimation reads the transactions waiting in the mempool and the fee rate each is paying, then infers the sat-per-vByte needed to get mined within a target number of blocks. A busier mempool pushes the next-block rate up. BitcoinDatabase computes this for you so you attach a fee that confirms without overpaying.

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Stop running a node. Just query Bitcoin.

Run your first query now and get on-chain data back by REST API, SQL or dashboard, indexed from the genesis block. Informational on-chain data only, not financial advice.

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Indexed from genesis · REST · SQL · dashboards · addresses, transactions, UTXOs, metrics