The explore.block.space API

explore.block.space runs the open-source Mempool explorer, and with it the Mempool REST API: what is enabled, where it is documented, and real responses.

explore.block.space is block.space's sibling block explorer, the transaction view of the same chain. Its code is the public repository BLOCKdotSPACE/blockspace-explorer, a copy of the Mempool Open Source Project, which its README describes as "the fully-featured mempool visualizer, explorer, and API service". It reads Blockspace Holdings' node and indexers, and follows the repository's master branch: a push is deployed within about a minute, and a failed check puts the previous build back.

Where the API is documented #

The explorer serves its own REST API reference at https://explore.block.space/docs/api/rest. The reference is generated from the repository's API documentation file, so it lists every endpoint the Mempool code offers. This page does not copy it. It records what the deployment adds or leaves out, and shows a few real answers.

Paths #

The repository's web server configuration routes:

/api/v1/... to the Mempool backend's own API (fees, mining, difficulty, blocks with extras);
/api/... to the same backend under /api/v1/, so the Esplora-style paths (/api/blocks/tip/height, /api/tx/<txid>/status, /api/block-height/<h>) answer too;
/api/v1/ws and /ws to the backend's WebSocket.

What is switched on #

The deployment's configuration names the network mainnet and the backend electrum. Statistics and fiat prices are enabled. Lightning is disabled, and so is the Stratum feature: GET https://explore.block.space/api/v1/lightning/statistics/latest answered Cannot GET on 2026-10-20.

Examples #

All read 2026-10-20 at 09:44 UTC; the public form is shown.

https://explore.block.space/api/blocks/tip/height:

https://explore.block.space/api/v1/fees/recommended (sat/vB):

{"fastestFee": 3, "halfHourFee": 1, "hourFee": 1, "economyFee": 1, "minimumFee": 1}

https://explore.block.space/api/mempool:

{"count": 48622, "vsize": 25142046, "total_fee": 5822318, "fee_histogram": []}

https://explore.block.space/api/v1/blocks/972000, the first block of the list, trimmed:

{"id": "00000000000000000001f09a6919251b4c3dd5261ee68c8a17ec718667d35f20", "height": 972000,
 "timestamp": 1792330109, "tx_count": 4533, "size": 1852685, "weight": 3992990,
 "extras": {"totalFees": 997259, "medianFee": 0}}

https://explore.block.space/api/v1/difficulty-adjustment, trimmed:

{"progressPercent": 29.315476190476193, "difficultyChange": 5.965006488566682,
 "remainingBlocks": 1425, "nextRetargetHeight": 973728}

https://explore.block.space/api/tx/79103146f41684b035467d25951562db830f88e97a1ffa3a56036048da0fa491/status:

{"confirmed": true, "block_height": 972000,
 "block_hash": "00000000000000000001f09a6919251b4c3dd5261ee68c8a17ec718667d35f20", "block_time": 1792330109}

How it differs from the block.space API #

The explorer reports the chain as Bitcoin Core and Mempool see it: sizes, weights, fees, the mempool. It knows nothing of BTI's books. The same block 972000 on the block.space API adds the attributed, claimed and content bytes. The two report different sizes for it: the explorer's size is 1,852,685 bytes and block.space's ledger total_bytes is 1,852,602, 83 bytes fewer. Compare like with like before mixing the two.