Your crypto stays with you
What Crypto Master can see, what it cannot do, and how to check it yourself — before you trust it with anything.
We cannot move anything
Crypto Master reads a history. It holds none of your crypto and signs no transaction: it has neither your private key, nor your recovery phrase, nor any exchange key it uses to trade or withdraw. So there is no path, on our side, by which your funds could move.
A wallet: its public address, and nothing else
To follow a wallet, you paste its public address — the one you give out to receive funds. No key, no signature: we only read what the blockchain already shows to everyone. For Bitcoin on a hardware wallet, the extended public key (xpub) is enough: it lets us see, never spend.
Never type in your recovery phrase, here or anywhere else. Crypto Master will never ask for it, and no legitimate service will.
An exchange: a read-only key you can check
For an exchange, the app uses an API key that you create yourself on the exchange. Five things to know before pasting it:
- Create it read-only. For each exchange, the connection screen says which boxes to tick — and which to leave empty: withdrawal, transfer, trading.
- Check it on the exchange. In your list of keys, it must show read permissions only. If “withdraw” or “trade” appears, delete it and create another one. With a read-only key, the exchange itself refuses any order: that guarantee does not depend on us.
- It is only used to read. The software only queries histories — trades, deposits, withdrawals, balances. It contains no call that places an order or withdraws funds, and an automated check refuses any attempt to add one.
- It is encrypted. With AES-256 before it is saved, using an encryption key kept outside the database. It is never shown to you again: only its last four characters are.
- You remove it whenever you like. “Delete the keys” erases it from Crypto Master; deleting it on the exchange makes it unusable, immediately. Either way, what is already imported stays.
What we keep, and what we do not
What we keep
- Your transactions: date, type, quantities, fees.
- The public addresses of the wallets you follow.
- Your exchange API keys, encrypted.
- Your email address, and the hash of your password — never the password itself.
What we do not keep
- No private key, no recovery phrase.
- No exchange password: an API key is enough, and you are the one who creates it.
- None of your crypto: nothing is deposited with us.
- No data sold or rented out, no advertising.
The details — providers, retention periods, your rights — are in the privacy policy.
Your account
The site is served over HTTPS only. Repeated sign-in attempts are slowed down, the session cookie is out of reach of JavaScript, and changing your password closes sessions opened elsewhere.
Who is behind it
MG INNOVATIONS (EURL) · Paris · SIRET 88887474000028
Crypto Master is published by a French company run by Guillaume Melnik, and hosted by OVH, in France. The publisher’s full identity is in the legal notice.
Try it without giving anything
The demo opens on a fictional portfolio, with no sign-up: no address, no key, no email. You see what the app does with your data before trusting it with any.