Privacy
This site is static: there is no server of ours that receives anything you type. There are no analytics, trackers, cookies or third-party scripts. The page itself is served by GitHub Pages, which, like any web host, can see your IP address when you load it.
What is sent to mempool.space, and when
Some tools need live blockchain data. Those requests go directly from your browser to the public mempool.space API, which will see your IP address and what you looked up. If you pick Signet or Testnet4 in a tool’s network selector, the same requests go to mempool.space’s test-network API (mempool.space/signet/api or mempool.space/testnet4/api) instead, and no prices are fetched. Specifically:
| Tool | What is sent | When |
|---|---|---|
| Address checker | Nothing — validation is local. The address is sent only if you press the optional “Look up balance” button | Only on that button |
| Quantum exposure checker | The address you enter (needed to see whether it has been spent from) | When you press “Check” |
| Transaction explainer | The transaction ID you enter; BTC price | When you press “Explain” |
| Payment status & stuck transaction helper | The transaction ID or address you enter; fee rates and chain height. The CPFP builder sends the stuck txid (and fetches the raw parent for legacy outputs) — never your destination address, keys or the PSBT | When you press “Check”, and every 30 seconds while auto-refresh is on |
| Converter | Request for the current price, and the date you pick for historical prices | On page load / when you look up a date |
| Receive address QR | Nothing by default. If you enter an amount in USD/EUR, only a price request is sent (not the address) | Only when using a fiat unit |
| Payment request decoder | Nothing by default. Optional USD/EUR conversion fetches only the price | Only on the optional price button |
| Fee checker | Request for current fee rates and BTC price | On page load and on refresh |
Looking up your own addresses or transactions on any public service can link them to your IP address. If that matters to you, use Tor or a VPN, or run your own node with a mempool instance.
We never ask for private keys or seed phrases, and nothing on this site can move your bitcoin.