Signing a Message

When a web application is connected to Phantom, it can also request that the user signs a given message. Applications are free to write their own messages which will be displayed to users from within Phantom's signature prompt. Message signatures do not involve network fees and are a convenient way for apps to verify ownership of an address.
In order to send a message for the user to sign, a web application must: 
1.Provide a hex or UTF-8 encoded string as a Uint8Array.
2.Request that the encoded message is signed via the user's Phantom wallet.
The handleSignMessage section of our developer sandbox provides an example of signing a message.
For more information on how to verify the signature of a message, please refer to tweetnacl-js.
signMessage()
request()
const provider = getProvider(); // see "Detecting the Provider"
const message = `To avoid digital dognappers, sign below to authenticate with CryptoCorgis`;
const encodedMessage = new TextEncoder().encode(message);
const signedMessage = await provider.signMessage(encodedMessage, "utf8");
const provider = getProvider(); // see "Detecting the Provider"
const message = `To avoid digital dognappers, sign below to authenticate with CryptoCorgis`;
const encodedMessage = new TextEncoder().encode(message);
const signedMessage = await provider.request({
    method: "signMessage",
    params: {
         message: encodedMessage,
         display: "hex",
    },
});
Support for "Sign In With" Standards
Applications that rely on signMessage for authenticating users can choose to opt-in to one of the various Sign In With (SIW) standards. You can read more about them here.
Last modified 3mo ago