> ## Documentation Index
> Fetch the complete documentation index at: https://cosmos-docs-cosmjs-docs.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Injected Wallets

> Integrate browser wallet extensions like Keplr, Leap, and Cosmostation with CosmJS

In browser environments, users typically sign transactions through a wallet
extension like [Keplr](https://www.keplr.app/),
[Leap](https://www.leapwallet.io/), or [Cosmostation](https://cosmostation.io/).
These extensions inject a global object (e.g. `window.keplr`) that can produce
an `OfflineSigner` for any supported chain.

## Basic Integration

```typescript theme={"system"}
import { SigningStargateClient, GasPrice } from "@cosmjs/stargate";

const chainId = "cosmoshub-4";

// 1. Ask the extension to enable access for this chain
await window.keplr.enable(chainId);

// 2. Get an OfflineSigner from the extension
const signer = window.keplr.getOfflineSigner(chainId);

// 3. Use it exactly like a local wallet
const client = await SigningStargateClient.connectWithSigner(
  "https://rpc.my-chain.network",
  signer,
  { gasPrice: GasPrice.fromString("0.025uatom") },
);

const [{ address }] = await signer.getAccounts();
const result = await client.sendTokens(
  address,
  "cosmos1recipient...",
  [{ denom: "uatom", amount: "1000000" }],
  "auto",
);
```

The key insight: once you have an `OfflineSigner`, the rest of the code is
identical whether the keys come from a mnemonic, Keplr, Leap, or a Ledger
device. This is the power of the `OfflineSigner` abstraction.

## Choosing the Signing Mode

Keplr and similar wallets offer multiple signer variants:

```typescript theme={"system"}
// Amino only — broadest compatibility, required for Ledger via Keplr
const aminoSigner = window.keplr.getOfflineSignerOnlyAmino(chainId);

// Sync — returns both Direct and Amino signers simultaneously
const autoSigner = window.keplr.getOfflineSigner(chainId);

// Async — auto-selects Direct for mnemonic accounts, Amino for Ledger accounts
const asyncSigner = await window.keplr.getOfflineSignerAuto(chainId);
```

For most applications, `getOfflineSigner` is the right choice. It
synchronously returns a signer that implements both `OfflineDirectSigner` and
`OfflineAminoSigner`. Use `getOfflineSignerAuto` when you need async
auto-detection — it returns `Promise<OfflineSigner>` and automatically selects
Amino for Ledger-based accounts.

## Detecting the Extension

Wallet extensions need a moment to inject their global object. A common pattern:

```typescript theme={"system"}
function getKeplr(): Keplr | undefined {
  if (typeof window === "undefined") return undefined;
  return window.keplr;
}

window.addEventListener("load", () => {
  const keplr = getKeplr();
  if (!keplr) {
    alert("Please install the Keplr extension");
  }
});
```

## Suggesting a Chain

If the user's wallet doesn't know about your chain yet, you can suggest it:

```typescript theme={"system"}
await window.keplr.experimentalSuggestChain({
  chainId: "my-testnet-1",
  chainName: "My Testnet",
  rpc: "https://rpc.my-testnet.example",
  rest: "https://lcd.my-testnet.example",
  bip44: { coinType: 118 },
  bech32Config: {
    bech32PrefixAccAddr: "cosmos",
    bech32PrefixAccPub: "cosmospub",
    bech32PrefixValAddr: "cosmosvaloper",
    bech32PrefixValPub: "cosmosvaloperpub",
    bech32PrefixConsAddr: "cosmosvalcons",
    bech32PrefixConsPub: "cosmosvalconspub",
  },
  currencies: [{ coinDenom: "ATOM", coinMinimalDenom: "uatom", coinDecimals: 6 }],
  feeCurrencies: [{ coinDenom: "ATOM", coinMinimalDenom: "uatom", coinDecimals: 6 }],
  stakeCurrency: { coinDenom: "ATOM", coinMinimalDenom: "uatom", coinDecimals: 6 },
});
```