OpenNum
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Frequently asked questions

Last updated: 21 June 2026

OpenNum turns a Bitcoin Ordinals inscription number into a public, ownable identity — a profile, a payable handle, and a place to receive signed messages.

What is OpenNum?

An identity protocol on Bitcoin. Your inscription number becomes your public identity: a searchable profile, a way to receive BTC, and a wall of provably-signed messages.

Is it custodial?

No. OpenNum never holds your Bitcoin, your inscriptions, or your keys. Every action is signed by your own wallet.

How do I register?

Connect your Unisat wallet, pick an inscription you own, and sign a message. That binds the number to your wallet as your active OpenNum identity.

Does it cost anything?

Registration is free. You only pay normal Bitcoin network fees if and when you send BTC.

One wallet, one active number — why?

Each wallet activates one flagship OpenNum at a time. Extra numbers you hold can be activated in other wallets or listed for sale. This is deliberate: it keeps a clean, single public identity per wallet and keeps desirable numbers in circulation rather than frozen. See whitepaper §10.

What happens when I transfer or sell the inscription?

The identity goes dormant. The new on-chain owner can claim it by signing with their wallet, starting a fresh profile. Messages from the previous holder are archived, not deleted.

How do messages work?

Public messages on a profile are signed by the sender’s active OpenNum, so every message is provably from a real identity — no bots. You can withdraw your own messages; a profile owner can hide messages shown on their page.

How do offers and trading work?

OpenNum doesn’t hold funds or execute trades. Mark your number “open to offers,” and buyers reach you via the linked marketplace (for example, Satflow). Trades settle off OpenNum.

Why do I have to sign every action?

Each signature proves you authorize that specific action with your own wallet. That’s what makes OpenNum non-custodial and tamper-proof — no password, no account takeover.

OpenNum is non-custodial. Ownership follows the inscription on Bitcoin.
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