What you get#
Onekey exposes mempool.space as 6 endpoints behind one API key: 5 endpoints return one record (data is an object) and 1 endpoint return a list (data is an array). Every answer uses the same envelope (success, data, metadata, error), the cost is reported in metadata.credits_charged, and fields are mapped onto the unified schema so the code you write for mempool.space also works for the rest of the finance & markets category.
Endpoints#
| Endpoint | What it does | Parameters | Credits | Status |
|---|---|---|---|---|
address | Address totals (mempool.space). | address* | 1 | beta |
difficulty_adjustment | Bitcoin difficulty adjustment progress and estimate. | - | 1 | beta |
fees_recommended | Recommended fee rates (sat/vB) by urgency. | - | 1 | beta |
prices | Bitcoin price in major fiat currencies. | - | 1 | beta |
recent_blocks | Recent Bitcoin blocks (mempool.space v1 format). | - | 5 | beta |
tx | Bitcoin transaction summary by txid (mempool.space). | txid* | 1 | beta |
A * marks a required parameter. Each endpoint name links to its reference page with the full parameter table, caching window and a recorded response.
Make a request#
This calls mempool.address (1 credit, beta). Replace YOUR_API_KEY with your key; sign up, no card. 1,000 free credits cover the open-platform endpoints. Hard-to-reach platforms (X, TikTok, Instagram, Reddit, and others marked on their page) need a verified email and a purchased pack.
curl "https://api.onekey.dev/v1/mempool/address?address=1A1zP1eP5QGefi2DMPTfTL5SLmv7DivfNa" \
-H "x-api-key: YOUR_API_KEY"Fields you get back#
These unified fields come back from mempool.space, with the same names as on every other platform. The count is how many of its 6 mapped endpoints return the field; a field the source lacks is null, never missing. 28 platform-specific fields (ext.<name>) come on top, documented on each endpoint page.
| Field | Type | Endpoints |
|---|---|---|
entity.date | ISO 8601 date | 4 |
entity.id | string | 3 |
package.version | string | 1 |
The full schema is in Unified schema.
Pricing#
mempool.space calls cost 1 to 5 credits, flat per endpoint. Free when served from cache (0.2 credit for a cached response over 100 KB). Invalid, failed or not-found calls are not charged. See pricing for credit packs.