--- title: Polkadot-JS Guides description: Discover Polkadot-JS tools for developers and power users, including UI, extension, API, and phishing protection. url: https://developer.polkadot.com/wiki/general/polkadotjs/ word_count: 892 token_estimate: 1428 version_hash: sha256:0600ae9a5e85418adfe842c72ca5d33f6a6ec02598cc5101cbd0f60e7807d7ed last_updated: 2026-11-01T15:55:43+00:00 ---

Polkadot-JS is for developers and power users only. Explore Polkadot with secure and user-friendly wallets listed on the wallet options page. If you need help using the Polkadot Developer Interface, you can contact the Polkadot Support Team.

!!!info We support only the use of the [**Polkadot Developer Interface**](https://polkadot.js.org/apps/#/explorer) together with the [**Polkadot Developer Signer**](https://polkadot.js.org/extension/), [**Ledger**](https://www.ledger.com/ledger-live) and [**Polkadot Vault**](https://www.parity.io/technologies/signer/) for signing transactions. We do not provide support for third party applications. This section of the Polkadot Wiki is dedicated to advanced guides for the Polkadot-JS tooling. [**Polkadot-JS**](https://polkadot.js.org/) is a collection of tools that interfaces with Relay Chains and parachains in a granular way. The tools include: - [The Polkadot Developer Interface](#polkadot-developer-interface) - [The Polkadot Developer Signer](#polkadot-developer-signer) - [The Polkadot-JS API](../../reference/tools/polkadot-js-api.md) - [The Polkadot-JS Phishing List](#polkadot-js-phishing-list) Below we describe the different components of Polkadot-JS. For more information about Polkadot-JS you can consult the [**official documentation**](https://polkadot.js.org/docs/). ## Polkadot Developer Interface The Polkadot Developer Interface is an application that loads in your browser. There is a standard DNS [**hosted version**](https://polkadot.js.org/), which always has the latest features, and an [**IPFS version**](https://dotapps.io/) that is less frequently updated but is more decentralized. This is also often referred to as Polkadot-JS Apps, UI or the Apps UI. In the Wiki pages we will always refer to Polkadot Developer Interface. Polkadot-JS Apps has many capabilities that go beyond basic wallet functions such as account creation and sending or receiving transactions. See the [**dedicated section**](./polkadotjs-ui.md) for more information about the UI. ### Polkadot Developer Interface Desktop App The Polkadot Developer Interface also exists as a [**desktop application**](https://github.com/polkadot-js/apps/releases/) for Windows, Mac and Linux. The main advantage of using it is that by default it stores encrypted accounts on the filesystem instead of browser's local storage. Local storage is susceptible to attacks using XSS (Cross-Site Scripting). There's no such risk when with files stored on disk. The desktop app uses the [**Electron**](https://www.electronjs.org/) framework. It provides the same features as web app, the only difference being different account storage. !!!info Ledger not supported The desktop application does not support Ledger accounts. If you need a cold storage solution you can try Parity Signer (aka Polkadot Vault). ### Querying On-chain Data Let's see how we can query on-chain data with Polkadot Developer Interface on the Polkadot network with an example. To find out the current value for existential deposit, navigate to Developer > Chain state > Constants and query the balances pallet for existential deposit as shown in the snapshot below. You need to click on the plus button to execute the query. The value displayed is in [plancks](../learn/learn-DOT.md#the-planck-unit) ![query chain state](../assets/chain-state-constant.png) ## Polkadot Developer Signer The [**Polkadot Developer Signer**](https://polkadot.js.org/extension/) is not a wallet _per se_ but an account management tool. It allows you to create accounts and also import accounts from [**Ledger**](./ledger.md) devices or Parity Signer, allowing the signing of [**extrinsics**](../learn/learn-transactions.md) using these accounts. It also allows you export existing accounts and restore accounts (given you have the required information to restore them). The extension is a robust key storage tool, i.e. even if you clear the cache of your browser your accounts will be retained. The extension will recognize any websites that have been flagged for malicious activity. For additional security, the extension will always ask if you want a specific website to access the account information on it. The extension does not let users interact directly with on-chain functions as one would find on a wallet app like Metamask, i.e. it does not allow you to transact or do anything else other than adding and managing accounts. However, it provides a simple interface for interacting with extension-compliant dApps such as the [**Polkadot Developer Interface**](https://polkadot.js.org/apps/#/explorer) and the [**Polkadot Staking Dashboard**](https://staking.polkadot.cloud/#/overview). !!!info Metadata Updates The browser extension is a tool that interacts with the Polkadot network, but it is disconnected from it when it is not in use. It is important you [**always check for metadata updates**](../learn/learn-guides-accounts.md#polkadot-developer-signer) before using the extension or other account management tools such as Parity Signer (aka Polkadot Vault). ## Polkadot-JS Phishing List The [**Polkadot-JS phishing list**](https://polkadot.js.org/phishing/) website is a community-driven curation of malicious actors and operators. The Polkadot Developer Signer uses this list to warn a user about suspicious URLs and addresses that are part of the list, and automatically blocks the account address. ## How-to guides - [Where to Download the Polkadot Developer Signer](../learn/how-to/signer-where-to-download.md)