mempool.space API
- Free allowance
- Public REST API with no key; rate limits are enforced but their size is not published; HTTP 429 on excess and a possible ban on repeated excess
- Verdict
- ★ qualifiesusable as stated; the read path was probed
- Cost
- free tier
- Identity
- anonymousno card, no phone
- Binding limit
- request-raterate limits enforced, size not published; HTTP 429 on excess
- Evidence
- documented5 sources; a first-party page was read and the sentence quoted
- Freshness
- stale on 2026-12-04checked 2026-11-03 (live); stale on 2026-12-04
| Free tier | Public REST API with no key; rate limits are enforced but their size is not published; HTTP 429 on excess and a possible ban on repeated excess unit unlimited; metered on none; Bulk block queries return up to 10 blocks per call; more needs an enterprise sponsorship. A keyless tip-height call answered HTTP 200. Enterprise starts at USD 1499 a month with higher limits by API key or IP allow-list. |
|---|---|
| Price | none stated |
| Limits |
Bulk path: none beyond 10 blocks a call without Enterprise. Storage terms: unverified, no page read states one. |
| Binding | request-rate The unpublished request limit, with a ban after repeated 429s, is the ceiling a keyless client meets. |
| Identity | anonymous The public API needs no account or key; a keyless call answered HTTP 200. Enterprise limits go through an API key or IP allow-list after signing up. |
| Egress | not metered in bytes; request limits of unpublished size apply |
| Per-object cap | 10 blocks per blocks-bulk call |
| Interface | rest GET https://mempool.space/api/... with no key, plus a WebSocket at wss://mempool.space/api/v1/ws; testnet, testnet4 and signet have their own paths endpoint: https://mempool.space/api |
| Tooling | curl or any HTTP client; mempool.js is the JavaScript client. The open-source stack can also be installed and run by the user on a rented or free machine, which is the last resort after the hosted public API and Enterprise. |
| Composes with | Keyless Bitcoin chain data and fee estimates; Enterprise raises the limits when the public API throttles. |
| Reliability | Past the limits the API answers HTTP 429 and repeated excess can ban the caller. |
| Notes | Keyless with unpublished limits. Bulk path: 10 blocks a call. Storage terms: unverified. |
| Evidence note | documented Limits and bulk cap are read from the vendor docs; a keyless call answered 200; the rate size is unpublished. |
| Parsed numbers |
|
Evidence 5
| date | source | what it proved |
|---|---|---|
| 2026-11-02 | mempool.space/docs/api/rest | limits are enforced, 429 on excess, possible ban |
| 2026-11-02 | mempool.space/docs/api/rest | bulk block queries are capped at 10 blocks |
| 2026-11-02 | mempool.space/enterprise | Enterprise starts at USD 1499 a month |
| 2026-11-02 | mempool.space/enterprise | higher limits come through API keys or IP whitelisting |
| 2026-11-02 | probe: https://mempool.space/api/blocks/tip/height | a keyless tip-height call answered HTTP 200 |
More fields 1
| bulk path | blocks-bulk, 10 blocks a call; more is Enterprise |
|---|
Unknown values 1
- retention stated: the field does not apply to this kind of offer