Your notifications reveal preferences. We treat them accordingly.

Information the service uses

Bitcoin Block Notifier uses your email address to verify access and deliver notifications. It also stores your selected algorithm, mining pool, optional Coinbase-tag filter, future block-height target, one-time price target, the reference price, source, and time recorded when that target was saved, preferred currency, UTC offset, and the block height at which each block-based notification was saved. When a price target is reached, the service records the observed reference price, source, and time used for that notification.

For a verified-address notification, the service processes the address and signed message needed to prove control. Pending challenges use a keyed, non-reversible fingerprint and an opaque label. After successful verification, the account database stores that fingerprint and a shortened display hint containing the address's first and last eight characters so you can distinguish saved addresses; it does not store the full address. A shortened hint can sometimes be correlated with public blockchain data. The monitoring service must retain the full address privately to watch it. The signature and its hash are not retained after verification.

Address monitoring is sensitive

Associating a Bitcoin address with an email account can reveal financial activity. A valid signed message proves control of that address at enrollment; it does not establish identity or legal ownership.

Never submit a seed phrase, private key, xpub, descriptor, or wallet backup. Bitcoin Block Notifier does not need them and will never ask for them.

Coinbase-tag submissions

When you save a pool notification using a Coinbase tag that is not already in the public catalogue, the notification becomes active immediately and the tag may be kept as a private pending candidate. Submitting a tag does not by itself make that tag public.

If that exact tag is later confidently observed in the Coinbase data of a public blockchain block attributed to the selected pool and algorithm, it may enter the public catalogue. Blocks and Coinbase data in the accepted blockchain are inherently public and permanent, whether or not Bitcoin Block Notifier includes the tag in its catalogue.

A public catalogue entry does not identify the person who submitted it and is not linked publicly to an account or email address. Bitcoin Block Notifier does not promise that every submitted tag will be published or retained; an unobserved or unsuitable candidate may remain unpublished or be removed.

Donations

On-chain Bitcoin payments are public and irreversible. Confirm the network and destination before sending, and use a wallet compatible with the selected network.

Bitcoin Block Notifier does not publish donation addresses or donation totals in public statistics. Never provide a seed phrase, private key, extended public key, wallet descriptor, or wallet backup; the donation feature does not require them.

Where a Lightning option is available, an external Lightning provider may process ordinary request and payment information. The service does not promise anonymous or untraceable donations.

BLAKE2b public fallback

If the private BLAKE2b node is unavailable, the service can retrieve whole new blocks from mempool.guide and compare them with the watchlist inside the monitoring service. Requests contain public block identifiers and page offsets only. Watched addresses are never included in those requests or sent to mempool.guide.

What public statistics contain

The homepage shows exact site-wide totals for retained registered email accounts and saved notifications. These totals contain no email addresses or notification details. Mining-pool popularity and the most-watched future block height, when published, use grouped subscriber ranges. Public statistics never publish watched addresses, donation addresses, email addresses, Coinbase-tag filters, donation totals, or individual subscriber records.

Service providers and records

Infrastructure and email providers process the minimum information needed to host the service and deliver messages. Security, verification, delivery, and abuse-prevention records may be kept when needed to operate and protect the service.

Messages sent to our contact address are received and stored in Google Workspace, where the operator reads and answers them. The website does not copy contact messages or attachments into its database. Google may process message content, headers, and attachments to provide and protect the mail service. No scanner can guarantee that a file is safe. The message and correspondence may be retained as needed to answer the request and protect the service. Never send seed phrases, private keys, passwords, or wallet backups.

An unsubscribe link opens a dedicated confirmation page and never removes data merely by being opened. Before confirmation, the page may display the email address and number of active notifications associated with the link. Notification details are displayed only when the browser has a verified session for that same email; otherwise the holder may request a fresh, five-minute verification link. Anyone with a valid unsubscribe link can confirm removal, so unsubscribe links should not be shared.

Confirming removal permanently removes the email address, preferences, verification sessions, saved notifications, and notification delivery history. It also removes the email from the operator's algorithm-preference ledger on its next successful synchronization. The final confirmation email contains no notification count or details.

Removing a notification stops it from being active and starts any required watcher cleanup. Internet services and backups are not instantaneous, so deletion from every operational copy may take time.