The LI.FI Widget supports a range of configuration options, allowing you to:

  • Allow or deny specific chains, tokens, bridges, and exchanges.

  • Preselect default source and destination chains.

  • Choose default tokens for both source and destination.

  • Set the amount of the destination token.

  • Specify a destination address.

  • Customize various LI.FI SDK settings through the sdkConfig configuration.

These options enable precise control over the widget’s behavior and improve the user experience by adjusting it to specific needs and preferences.

​
LI.FI SDK configuration

The LI.FI Widget is built on top of the LI.FI SDK, leveraging its robust functionality for cross-chain swaps and bridging. The sdkConfig option allows you to configure various aspects of the SDK directly within the widget.

Let’s look at the example of configuring private RPC endpoints using the sdkConfig option.

import { LiFiWidget, WidgetConfig, ChainId } from '@lifi/widget';

const widgetConfig: WidgetConfig = {
  sdkConfig: {
    rpcUrls: {
      [ChainId.ARB]: ['https://arbitrum-example.node.com/'],
      [ChainId.SOL]: ['https://solana-example.node.com/'],
    },
  },
}

export const WidgetPage = () => {
  return (
    <LiFiWidget integrator="Your dApp/company name" config={widgetConfig} />
  );
};

In a production app, it is recommended to pass through your authenticated RPC provider URL (Alchemy, Infura, Ankr, etc).

If no RPC URLs are provided, LI.FI Widget will default to public RPC providers.

Public RPC endpoints can sometimes rate-limit users during periods of heavy load, leading to issues such as incorrectly displaying balances.

Please see other SDK configuration options in the Configure SDK section.

​
Initialize form values

The LI.FI Widget uses a number of form values that are used to fetch and execute routes.

These values are fromAmount, fromChain, fromToken, toChain, toToken and toAddress.

They are most often set by using the Widget UI but they can also be initialized and updated programmatically.

By configuring these options, you can streamline the user experience, ensuring that the widget is preloaded with the desired chains, tokens, amount and address for a swap or bridge. This reduces the need for manual input and helps guide users through the intended flow.

You can initialize these values by either:

  • Widget config - by adding fromAmount, fromChain, fromToken, toChain, toToken or toAddress values to the widget config.

  • URL search params - when buildUrl in the widget config is set to true, by adding them to the URL search params in the url of the page the widget is featured on.

When setting form values via config or URL search params you will see any corresponding form field UI updated to reflect those values.

​
Initializing by widget config

The LI.FI Widget allows you to preconfigure default chains and tokens, making it easy to set up your desired swap or bridging parameters right from the start. Below is an example of how to configure the widget with specific default chains, tokens, amount, and send to address values.

import type { WidgetConfig } from '@lifi/widget';
import { ChainType } from '@lifi/widget';

const widgetConfig: WidgetConfig = {
  // set source chain to Polygon
  fromChain: 137,
  // set destination chain to Optimism
  toChain: 10,
  // set source token to USDC (Polygon)
  fromToken: '0x3c499c542cEF5E3811e1192ce70d8cC03d5c3359',
  // set source token to USDC (Optimism)
  toToken: '0x0b2C639c533813f4Aa9D7837CAf62653d097Ff85',
  // set source token amount to 10 USDC (Polygon)
  fromAmount: 10,
  // set the destination wallet address
  toAddress: {
    address: '0x29DaCdF7cCaDf4eE67c923b4C22255A4B2494eD7',
    chainType: ChainType.EVM,
  },
};

export const WidgetPage = () => {
  return (
    <LiFiWidget integrator="Your dApp/company name" config={widgetConfig} />
  );
};

​
Initializing by URL search params

To initialize form values in the widget using URL search params you will need to ensure that buildUrl is set to true in the widget config.

import type { WidgetConfig } from '@lifi/widget';

const widgetConfig: WidgetConfig = {
  // instruct the widget to use and build url search params
  buildUrl: true,
};

You can then feature the URL search params in the URL when navigating to the page that features the widget.

https://playground.li.fi/?fromAmount=20&fromChain=42161&fromToken=0xFd086bC7CD5C481DCC9C85ebE478A1C0b69FCbb9&toAddress=0x29DaCdF7cCaDf4eE67c923b4C22255A4B2494eD7&toChain=42161&toToken=0xaf88d065e77c8cC2239327C5EDb3A432268e5831

Its important to understand this will only work for the widgets initialization - dynamically changing the search params in the URL without a page load will not cause an update of the form values in the widget.

Config values override URL search params

If you want to use URL search params to populate the widget’s form values on initialization (or page load) its important that those form values are NOT featured in the config object used to initialize the widget. fromAmount, fromChain, fromToken, toAddress, toChain, and toToken should NOT be set on the widget config in order to allow the URL to perform the initial set up of the widgets state.

On first page load if you have form values in both the config and the URL then the URL search params will be rewritten to match the config values and the widget form will be populated with the values presented in the config.

​
Update form values

After the widget has initialized there are two ways you can update the form values in the widget

  • Using the widget config - this uses reactive values in the config and requires some management of those values for updates

  • Using the formRef - this provides an function call that you can use to update values in the widgets form store.

Note that when buildUrl is set to true in the widget config both methods should also update the URL search params as well as the value displayed in the widget itself.

​
Updating by widget config

Once the widget has initialized you can update the form values in the widget by updating the widget config.

To perform an update you should only include the form values in the config that you want to change and ensure these changes are passed to the Widget.

For example, if you want to change the fromChain and fromToken and nothing else you should include only include those values

In addition to the form values you want to change you should also set a formUpdateKey. This needs to be a unique, randomly generated string and is used to ensure that the form values are updated in the widget - essentially forcing an update. This can avoid some edge case issues that might arise when setting values in the widget via a mix of config and user actions via the widgets UI.

Here is an example of what your config would look like.

import type { WidgetConfig } from '@lifi/widget';

const widgetConfig: WidgetConfig = {
    fromChain: 10,
    fromToken: ‘0x94b008aA00579c1307B0EF2c499aD98a8ce58e58’,
    // use the date object to generate a unique value
    formUpdateKey: new Date().valueOf().toString()
    // config may still feature other config values but 
    // should not include other form values…
}

You can also reset the form values and their fields to an empty state using undefined. This example resets only the fromChain and fromToken form values.

import type { WidgetConfig } from '@lifi/widget';

const widgetConfig: WidgetConfig = {
    fromChain: undefined,
    fromToken: undefined,
    // use the date object to generate a unique value
    formUpdateKey: new Date().valueOf().toString()
    // config may still feature other config values but 
    // should not include other form values…
}

Here undefined used to reset a the widgets form value to an empty state. The absence of a property from the widget config object means that property will remain unchanged.

State management with widget config When using config to update widgets form values it is often a good choice to consider using an application state management library to store your widget config. There are many options to choose from such as Zustand, MobX, Redux or even React context.

For example, if you were to use Zustand as your state management tool you could use Zustand’s API to access and set values on your config from any part of your application. In addition you would also be able to use Zustand’s equality functionality, such as the built-in shallow function, to ensure that your widget config is only used to update the instance of the LiFi Widget when necessary. This should be beneficial for optimizing re-renders.

You can find an example that uses Zustand to manage widget config in the widget repository.

​
Updating by form ref

This method provides developers a way to set the form values directly in the widget without making changes to the widget config. By passing a ref object to the widget you can access a function to set values directly on the widgets form state. See the example below.

import type { FormState } from '@lifi/widget';
import { LiFiWidget } from '@lifi/widget';

export const WidgetPage = () => {
  const widgetConfig: WidgetConfig = {
    buildUrl: true, 
  };
  
  const formRef = useRef<FormState>(null);
  
  const handleClick = () => {
    formRef.current?.setFieldValue( ‘fromChain’, 10, { setUrlSearchParam: true });
  };

  return (
    <>
      <LiFiWidget 
        integrator="Your dApp/company name" 
        config={widgetConfig} 
        formRef={formRef}
      />
      <button onClick={handleClick} type="button">Set fromChain to Optimism</button>
    </>
  )
}

Notice the use of setFieldValue function.

formRef.current?.setFieldValue( ‘fromChain’, 10, { setUrlSearchParam: true });

Once initialized the setFieldValue function can be called to set the form value, note that setUrlSearchParam will ensure the url is updated if you have buildUrl set to true in your widget config.

Here are some examples of usage.


// fromChain and fromToken can be set independently but you might also find that you want to set them at the same time
formRef.current?.setFieldValue( 
    'fromChain',
    10, 
    { setUrlSearchParam: true }
);
formRef.current?.setFieldValue(
    'fromToken', 
    '0x94b008aA00579c1307B0EF2c499aD98a8ce58e58', 
    { setUrlSearchParam: true }
);

// To reset fromChain and fromToken
formRef.current?.setFieldValue( 
    'fromChain',
    undefined, 
    { setUrlSearchParam: true }
);
formRef.current?.setFieldValue(
    'fromToken', 
    undefined 
    { setUrlSearchParam: true }
);

​
Configure allow and deny options

We provide allow and deny configuration options to control which chains, tokens, bridges, and exchanges can be used within your application. Here’s how you can set up and use these options:

import { LiFiWidget, WidgetConfig } from '@lifi/widget';

const widgetConfig: WidgetConfig = {
  // disable BSC from being shown in the chains list
  chains: {
    deny: [56],
  },
  // allow bridging through Stargate bridge only
  bridges: {
    allow: ['stargate'],
  },
};

export const WidgetPage = () => {
  return (
    <LiFiWidget integrator="Your dApp/company name" config={widgetConfig} />
  );
};

To control which tokens appear in the from and to lists, use the allow and deny options:

  • If defined at the top level of the tokens object, they apply to both lists.
  • If defined inside the from or to objects, they apply only to that specific list.
  • If an allow list is defined, only tokens included in it are allowed.
  • If no allow list is defined, all tokens are allowed unless they are explicitly included in deny.
  • A token must pass both the top level allow/deny check and the check for the current list (from or to) to be considered allowed.
import { LiFiWidget, WidgetConfig } from '@lifi/widget';

const widgetConfig: WidgetConfig = {
  tokens: {
    // Top-level allow/deny apply to BOTH 'from' and 'to' lists
    allow: [
      {
        address: '0x0000000000000000000000000000000000000000',
        chainId: 1,
      },
    ],
    deny: [
      {
        address: '0x0000000000000000000000000000000000000000',
        chainId: 137,
      },
    ],
    // 'from' list-specific allow/deny complements top-level settings
    from: {
      allow: [
        {
          address: '0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2',
          chainId: 1,
        },
      ],
      deny: [
        {
          address: '0x0000000000000000000000000000000000000000',
          chainId: 1,
        },
      ],
    },
    // 'to' list-specific allow/deny
    to: {
      allow: [
        {
          address: '0x0000000000000000000000000000000000000000',
          chainId: 137,
        },
      ],
      deny: [
        {
          address: '0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2',
          chainId: 1,
        },
      ],
    },
  },
};

export const WidgetPage = () => {
  return (
    <LiFiWidget integrator="Your dApp/company name" config={widgetConfig} />
  );
};

Apart from the allow and deny options, the tokens option can be configured to include other tokens or featured tokens that will appear at the top of the corresponding list of tokens.

import { LiFiWidget, WidgetConfig } from '@lifi/widget';

const widgetConfig: WidgetConfig = {
  tokens: {
    // Featured tokens will appear on top of the list
    featured: [
      {
        address: '0x2fd6c9b869dea106730269e13113361b684f843a',
        symbol: 'CHH',
        decimals: 9,
        chainId: 56,
        name: 'Chihuahua',
        logoURI: 'https://s2.coinmarketcap.com/static/img/coins/64x64/21334.png',
      },
    ],
    // Include any token to the list
    include: [
      {
        address: '0xba98c0fbebc892f5b07a42b0febd606913ebc981',
        symbol: 'MEH',
        decimals: 18,
        chainId: 1,
        name: 'meh',
        logoURI: 'https://s2.coinmarketcap.com/static/img/coins/64x64/22158.png',
      },
    ],
  },
};

export const WidgetPage = () => {
  return (
    <LiFiWidget integrator="Your dApp/company name" config={widgetConfig} />
  );
};
with_featured_tokens

With featured tokens

without_ft_tokens

Without featured tokens

​
Destination address

There are use cases where users need to have a different destination address. Usually, they can enter the destination address independently.

Still, the widget also has configuration options to pre-configure the destination address or create a curated list of wallet addresses to choose from.

send_to_wallet

Send to wallet button

send_to_wallet_view

Send to wallet view

​
Configure single destination address

Developers can use the toAddress option to configure a single destination address. The address and chainType properties are required, while the name and logoURI properties are optional.

import { ChainType, LiFiWidget, WidgetConfig } from '@lifi/widget';

const widgetConfig: WidgetConfig = {
  toAddress: {
    name: 'Vault Deposit',
    address: '0x0000000000000000000000000000000000000000',
    chainType: ChainType.EVM,
    logoURI: 'https://example.com/image.svg',
  },
};

export const WidgetPage = () => {
  return (
    <LiFiWidget integrator="Your dApp/company name" config={widgetConfig} />
  );
};

​
Configure a curated list of wallet addresses

Developers can use toAddresses option to configure a curated list of wallet addresses.

import { ChainType, LiFiWidget, WidgetConfig } from '@lifi/widget';

const widgetConfig: WidgetConfig = {
  toAddresses: [
    {
      name: 'Lenny',
      address: '0x552008c0f6870c2f77e5cC1d2eb9bdff03e30Ea9',
      chainType: ChainType.EVM,
      logoURI: 'https://example.com/image.svg',    
    },
    {
      address: '0x4577a46A3eCf44E0ed44410B7793977ffbe22CE0',
      chainType: ChainType.EVM,
    },
    {
      name: 'My sweet solami',
      address: '6AUWsSCRFSCbrHKH9s84wfzJXtD6mNzAHs11x6pGEcmJ',
      chainType: ChainType.SVM,
    },
  ],
};

export const WidgetPage = () => {
  return (
    <LiFiWidget integrator="Your dApp/company name" config={widgetConfig} />
  );
};

Using this configuration, when users click on the Send to wallet button, they will open a pre-configured list of addresses from which to choose, skipping the step where they can manually enter the address.

Together with configuring the wallet list, developers can make the destination address required to be filled out. Please see Required destination address for more details.

opt_dest_address

Optional destination address

curated_list_wallet

A curated list of wallet addresses

​
Explorer URLs

In the widget there are numerous points where a user can click to open an explorer in a separate browser tab in order to find out more information about a transaction or an address. Any buttons or links in the widget that present this icon will direct the user to an explorer.

We have default behaviors in relation to opening explorers and we can also use widget config to override and change these behaviors.

​
Default behavior for chains

Often when trying to direct a user to an explorer the widget will know which chain relates to a transaction or address and it will present an explorer that matches that chain.

For example, after the user has executed a transaction, on the transaction details page they can click on the “Token allowance approved” explorer button to see more detail about that approval. If the approval was done using the Optimism chain then a new tab would open taking the user to optimistic.etherscan.io to show them more information about that approval.

If no explorer can be found in relation to a chain then the user will be directed to LiFi’s explorer.

​
Default behavior for internal explorers

An internal explorer is an explorer that is the preferred choice of an organization that is building an app using the widget. In some parts of the widget we use an internal explorer rather than attempting to find an explorer for a specific chain.

For example, once the user has completed a transaction and is on the transaction details page they are presented with a transfer ID (see below). This is accompanied by a link which allows the user to open an explorer in order to find more information about that transaction. There is no attempt to find a chain specific explorer. The default explorer used is LI.FI own internal explorer and users will be directed to https://scan.li.fi

​
Overriding the explorer URLs

It’s possible to override the explorer URLs that widget uses via the widget config. We can do this for specific chains and for the internal explorer. You can use your own explorer urls for multiple chains and at the same time state your own alternative for the internal explorer.

​
Overriding explorers for a chain

In the widget config you can override chains by adding an entry to the explorerUrls object: you provide the chain id as a key and the base url of the explorer as the value.

import type { WidgetConfig } from '@lifi/widget';

const widgetConfig: WidgetConfig = {
  explorerUrls: {
    42161: ['https://scan.li.fi']
  },
}

The explorer specified above will be used only for that chain, in the above example this would be Arbitrum. For other chains that aren’t specified in the explorerUrls object the widget will still present the default behavior (as stated above).

​
Overriding explorers for the internal explorer

In the widget config you can override the internal explorer by adding an entry to the explorerUrls object: you provide internal as a key and the base url of the explorer as the value.

import type { WidgetConfig } from '@lifi/widget';

const widgetConfig: WidgetConfig = {
  explorerUrls: {
    internal: ['https://jumper.exchange/scan']
  }
}

Any places within the widget that use the internal explorer will now use the url stated in the config rather than the default.

​
Address and transaction pages

The widget assumes that the explorer will provide pages for addresses at /address/:address and for transactions at /tx/:hash and will attempt to navigate the user to those pages when the users clicks the related buttons.

A link to a wallet address would look like:

https://scan.li.fi/address/0xb9c0dE368BECE5e76B52545a8E377a4C118f597B

And a link to a transaction would look like:

https://scan.li.fi/tx/0x05dbd8d3be79ad466e7d2898f719cc47b1b3b545cf4782aece16e11849ddd24b

The widget assumes that any explorer used with the widget will follow this convention.