Privacy Policy
bitcoin-puzzle.net — last updated 17 August 2026
This site is a tool for taking part in the Bitcoin Puzzles: it builds the command for the worker that runs on your own machine and, if you want, rents GPUs on vast.ai for you. There is no sign-up, no password and no email. You do not create an account here.
What stays in your browser (and only there)
These are written to your browser's localStorage. They are not cookies, they are not
sent anywhere on their own, and they never leave your device except when you use the feature that
depends on them:
| Data | What for | How to delete |
|---|---|---|
| vast.ai API key | Talking to vast.ai on your behalf (listing offers, creating and stopping instances) | The remove-key button, on the screen itself |
| Your Bitcoin wallet address | Crediting the work your worker does | Clear the field, or clear the site's data in your browser |
| Alias, language and UI preferences | Remembering how you left the interface | Clear the site's data in your browser |
Your vast.ai key
The key is yours and the site does not store it. It lives in your browser and is
sent with each request, in the X-Vast-Api-Key header, only so the server can pass it on to
the vast.ai API for that call. Once the request ends it is not written to a database, a file or a log.
That is why the server image can be public: there is no vast.ai secret inside it.
What vast.ai does with your account is governed by their privacy policy.
A caveat we would rather state: since this site started showing ads, a Google script runs on the same page where your key is kept. We do not send it anywhere and we do not store it — that still holds — but we can no longer guarantee by construction that no third-party code can reach it. If that bothers you, use the key only while operating and remove it afterwards, with the button on the screen itself.
Your wallet address
The worker running on your machine reports to our server how much of the search space it scanned, and uses your address as the label for that credit. We store that volume per address.
The address is no longer published. Not in the ranking, not in the active worker list, not in the API behind them. In its place goes your alias, when you choose one, or a pseudonym derived from the address by hash — stable, so someone can be followed on the leaderboard, and with no address inside it.
The honest caveat: the pseudonym prevents HARVESTING (whoever downloads the leaderboard does not walk away with a list of wallets), but it is not absolute secrecy. Anyone who downloads a public list of blockchain addresses and hashes it can match a pseudonym to an address — it costs seconds of computer time. If the link between your identity and this activity is sensitive to you, use a wallet dedicated to it.
The ranking of wallets is the part that is opt-in: the accumulated total per wallet only enters it if you sign up, and you can leave from the same screen. An honest caveat: today the sign-up does not require proof that you own the address, so in principle a third party could sign up a wallet that is not theirs. This is a deliberate choice, not an oversight: requiring proof would mean asking for a wallet signature, and we would rather not impose that on someone who just wants to show up in the ranking. The effect is reversible — anyone signed up without meaning to can remove the entry on the same screen, without depending on us.
If you do not want that exposure, the practical answer is to use a wallet dedicated to this activity, separate from your others. Worth remembering that a Bitcoin address is public data on the blockchain by nature.
Worker telemetry
While your worker is mining it sends the server: your wallet address, an instance identifier, the scan speed, the status (running/stopped), the block it is working on, the hardware type and name (e.g. the GPU model) and the start and last-signal timestamps. This exists for the monitoring screen and so the server does not hand the same stretch to two workers. These fields appear in the public worker list.
The instance identifier includes a code derived from your machine (a hash of hardware identifiers). It contains neither your hostname nor your username in the clear, and the server does not store your IP in the database — but, being stable, it does allow noticing that different workers come from the same machine, including if you switch wallets. We do not ask for or keep a name, email or ID document; even so, this is more than "anonymous", and we would rather say so plainly.
Access logs
Like any server on the internet, ours logs the requests it receives, including the source IP address, to operate the service and limit abuse (there is a per-IP request limit). Those logs live in Google Cloud's infrastructure and are discarded under its default retention.
Ads and cookies
This site shows Google AdSense ads. Google and its partners may use cookies and identifiers to serve and measure ads, including ads personalised based on your visits to this and other sites.
- The site sets no first-party cookies. Any that exist come from Google.
- If you are in the European Economic Area, the UK or Switzerland, a consent dialog appears with Consent, Do not consent and Manage options — we deliberately chose the format where refusing costs one click, the same as accepting.
- You can turn off Google's personalised advertising at myadcenter.google.com, and see how Google handles this data in its partner sites policy.
What this site does NOT do
- It never asks for or stores the private key of any wallet of yours. The site never needs it.
- No account, no password, no email, no ID document.
- It does not sell or rent any data to third parties.
- It uses no third-party analytics. Fonts, icons and images are served by the site itself, with no CDN.
Your rights
The data that can be linked to you is your wallet address and whatever is in your browser. You control both directly: the key and the wallet you delete on the site itself, and the ranking sign-up you undo on the same screen where you made it. If you want us to delete the volume history tied to an address, write to the contact below — we will only ask for proof that the address is yours.
Children
The site is not intended for anyone under 18 and does not knowingly collect their data.
Changes
If this policy changes, the date at the top changes with it. Material changes will be announced on the home page itself.
Contact
Privacy questions or requests: contato@bitcoin-puzzle.net.