Authenticate with an external JWT

Recommended: JavaScript SDK for React Native

While this SDK is still supported, we recommend using newer JavaScript SDK, which is optimized for React Native, but also comes with a host of other benefits.

Bring Your Own Auth (BYOA) is an enterprise feature. Contact us in Slack or at hello@dynamic.xyz to enable it.

If you already issue your own JWTs (e.g. from Auth0, Firebase Auth, Supabase, or your own backend), you can exchange that JWT for a Dynamic session. After sign-in, the user behaves like any other Dynamic user — with access to wallets, user management, and the rest of the SDK. For concepts and configuration, see Bring Your Own Auth.

Issue a Dynamic-specific JWT from your auth provider — separate from your application’s normal access token — so the token Dynamic receives cannot be used to access resources on your own servers. See Bring Your Own Auth for the full recommendation.

Prerequisites

BYOA configured in your Dynamic dashboard (issuer, JWKS URL).
Dynamic client created and initialized (see the React Native quickstart).
Your backend issues a JWT with at least iss, sub, and exp claims.

Usage

Call signInWithExternalJwt on the Dynamic client’s external auth. Dynamic verifies the signature against your configured JWKS URL, validates the claims, and establishes a session.

React Native

import { dynamicClient } from '<path to client file>';

const signIn = async (externalJwt: string, externalUserId: string) => {
  try {
    await dynamicClient.auth.external.signInWithExternalJwt({
      externalJwt,
      externalUserId,
    });

  } catch (e) {
    console.error('Dynamic sign-in failed:', e);
  }
};

Parameters

Parameter	Type	Required	Description
`externalJwt`	`string`	Yes	The raw encoded JWT issued by your authentication provider.
`externalUserId`	`string`	Yes	The user ID in your authentication system. Must match the `sub` claim in the JWT — Dynamic derives the stored external user ID from the JWT server-side.

Bring Your Own Auth — Concepts, configuration, and JWT requirements.
Dynamic client reference — All methods available on the client.

Last modified on July 24, 2026

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React Native SDK Reference

Authenticate with an external JWT

Recommended: JavaScript SDK for React Native

Prerequisites

Usage

Parameters

Recommended: JavaScript SDK for React Native

​Prerequisites

​Usage

​Parameters

​Related

Prerequisites

Usage

Parameters

Related