Bitcoin Fee API vs mempool.space
mempool.space is the best-known Bitcoin mempool explorer. Satoshi API is a fee-intelligence API for apps and AI agents that need a direct answer: send now or wait?
The practical difference
mempool.space is built around human exploration: charts, blocks, transactions, addresses, and public mempool visibility. Satoshi API is built around app and agent decisions: fee recommendation, congestion context, copy-paste REST calls, and machine-readable discovery surfaces.
They are complementary. The question is whether your next step is to inspect the mempool visually or ship a feature that tells users when to broadcast.
Feature comparison
| Use case | mempool.space | Satoshi API |
|---|---|---|
| Visual mempool exploration | Excellent | Not the focus |
| Fee recommendation endpoint | Fee rates and mempool context | Decision-oriented /api/v1/fees/recommended |
| AI agent discovery | General web/API docs | llms.txt, agent card, OpenAPI, MCP |
| Self-hosted API layer | Possible with more stack surface | Designed as a Bitcoin Core REST layer |
| x402 paid API example | Not the focus | /x402/start and paid OpenAPI |
First API call
If you are building a wallet, bot, or AI agent, start with the free recommendation endpoint:
curl https://bitcoinsapi.com/api/v1/fees/recommendedFAQ
Is Satoshi API a mempool.space alternative?
Satoshi API is a mempool.space alternative for developers and AI agents that need fee recommendations and app-facing API responses. mempool.space remains excellent for visual block exploration and public mempool browsing.
Which is better for AI agents?
Satoshi API is usually better for AI agents because it exposes llms.txt, OpenAPI, an agent card, bitcoin-mcp, and a free fee recommendation endpoint that returns a decision-oriented response.
Can I use both Satoshi API and mempool.space?
Yes. A common pattern is to use mempool.space for visual confirmation and Satoshi API for production fee decisions, MCP tools, and self-hosted app workflows.