Knowledge base Identity
Identity and login
There is no account. There is a keypair on your device, and everything you do is signed with it.
Keys, not accounts
A Nostr identity is a secp256k1 keypair. The public key identifies you; the private key signs what you send. There is no registration step because there is nothing to register with — the key is generated locally and is valid the moment it exists.
Two encodings you will see:
| Form | What it is | Sharing it |
|---|---|---|
npub1… | Your public key | Safe. It is your address. |
nsec1… | Your private key | Never. It is you. |
Your nym is the display name you chose plus four hex characters taken from
your public key — SatoshiFan#a1b2. Names are not reserved and two people
can pick the same one; the suffix is what tells them apart, and it cannot be borrowed
without the key behind it.
Nobody holds a copy of your private key, so nobody can restore it. Lose it and the
identity is gone: not locked, gone. If an identity matters to you, copy its
nsec into a password manager now.
Ephemeral identities
Sign up on the welcome screen and Nymchat mints a keypair for you on the spot. What happens to it next is a setting — Generate Random Keypair Per Session, under Settings › Privacy & Security:
| Mode | Behaviour |
|---|---|
| Disabled (default) | The keypair persists across reloads, so your nym survives closing the tab and coming back. |
| Enabled | A brand-new identity every session. Nothing links this session to the last one. |
| Hardcore | A new keypair for every message sent. |
Nobody can reply to a pubkey that no longer exists. Private messages and group chats do not work reliably in hardcore mode, and settings will not sync. It is for shouting into a public channel and nothing else. Per-session mode has the same effect on settings sync, for the same reason.
There is also Auto Ephemeral Mode on Restart under Settings › Messaging & Display, which skips the welcome screen entirely and drops you straight into a fresh ephemeral session.
It hides you from other users: there is no name, email or phone number behind the key. It does not hide your IP address from the relays you connect to. Nymchat routes relay traffic through its own proxy by default, which keeps your address off third-party relays — see the privacy proxy — but if that matters to you, use Tor or a VPN as well.
Logging in with a Nostr account
The Login tab takes an identity you already have. Four ways in, in descending order of how much your key is exposed:
| Method | Where the key lives | Needs |
|---|---|---|
| Browser extension (NIP-07) | In the extension. Nymchat asks it to sign and never sees the key. | Alby, nos2x or similar |
| Remote signer (NIP-46) | On another device or service. Signing requests go to it. | Amber, nsecbunker, nsec.app |
| Bunker string | Same as above — paste a bunker:// URI instead of scanning. |
A signer that emits one |
| Paste an nsec | In this browser's or app's local storage. | Nothing |
Prefer an extension or a remote signer where you can. If you paste an nsec, turn
on identity encryption so the stored key is
not readable from the device.
A persistent identity gets you a nym that survives restarts, a profile other clients can see, settings that follow you between devices, and zaps that can actually be paid to you.
Your profile
Tap the "Your Nym" panel at the top of the sidebar to edit:
- Nickname — up to 20 characters.
/nickdoes the same thing from the composer. - Avatar and banner images.
- Bio — up to 150 characters.
- Bitcoin Lightning address — where zaps you receive are paid.
- Reveal this nym's private key — a collapsed section that shows the
nsecso you can back it up.
For a logged-in Nostr identity this is your ordinary Nostr profile (a kind 0
metadata event), so a change here shows up in every other Nostr client too.
Press and hold that same panel for two seconds and Nymchat wipes itself from the device immediately, without asking. See Panic wipe.