> ## 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.

# Send Transactions

> Build messages, estimate gas, sign, broadcast, and handle the full transaction lifecycle with CosmJS

Sending a transaction on a Cosmos SDK chain is a multi-step process: you build one or more messages, estimate gas, sign the transaction, broadcast it to a node, and then wait for block inclusion. This guide walks through each step using `SigningStargateClient`.

## Prerequisites

* **Node.js** v22 or later
* `@cosmjs/stargate` and `@cosmjs/proto-signing` installed
* An RPC endpoint for the target chain

<CodeGroup>
  ```bash npm theme={"system"}
  npm install @cosmjs/stargate @cosmjs/proto-signing cosmjs-types
  ```

  ```bash yarn theme={"system"}
  yarn add @cosmjs/stargate @cosmjs/proto-signing cosmjs-types
  ```

  ```bash pnpm theme={"system"}
  pnpm add @cosmjs/stargate @cosmjs/proto-signing cosmjs-types
  ```
</CodeGroup>

## Set Up a Signing Client

Create a wallet and connect a signing client. This example uses a mnemonic-based wallet for simplicity — see [Local Wallets](/cosmjs/v0.38.x/concepts/account/local-wallets) and [Injected Wallets](/cosmjs/v0.38.x/concepts/account/injected-wallets) for production options.

```typescript theme={"system"}
import { SigningStargateClient, GasPrice } from "@cosmjs/stargate";
import { DirectSecp256k1HdWallet } from "@cosmjs/proto-signing";

const wallet = await DirectSecp256k1HdWallet.fromMnemonic(
  "your mnemonic words here ...",
  { prefix: "cosmos" },
);
const [{ address: senderAddress }] = await wallet.getAccounts();

const client = await SigningStargateClient.connectWithSigner(
  "https://rpc.my-chain.network",
  wallet,
  { gasPrice: GasPrice.fromString("0.025uatom") },
);
```

<Warning>
  Never hard-code mnemonics in source files. Use environment variables or a secrets manager.
</Warning>

Setting `gasPrice` in the client options enables `"auto"` fee estimation for all transactions. Without it, you must pass an explicit `StdFee` to every transaction method.

## Transaction Lifecycle

Every transaction follows these steps:

1. **Build messages** — describe what the transaction should do
2. **Estimate gas** — simulate execution to determine fees
3. **Sign** — produce a cryptographic signature over the transaction bytes
4. **Broadcast** — send the signed transaction to a node
5. **Confirm** — wait for the transaction to be included in a block

The simplest path combines all steps in a single call:

```typescript theme={"system"}
const result = await client.sendTokens(
  senderAddress,
  "cosmos1recipientaddress...",
  [{ denom: "uatom", amount: "1000000" }],
  "auto",
);

console.info("Tx hash:", result.transactionHash);
```

The following pages break down each step in detail.

## Convenience Methods

`SigningStargateClient` provides high-level methods for the most common transactions. They construct the message internally and call `signAndBroadcast`:

```typescript theme={"system"}
const result = await client.sendTokens(
  senderAddress,
  "cosmos1recipientaddress...",
  [{ denom: "uatom", amount: "1000000" }],
  "auto",
  "thanks for lunch",
);
```

| Method                                                       | Description                                             |
| ------------------------------------------------------------ | ------------------------------------------------------- |
| `sendTokens(sender, recipient, amount, fee, memo?)`          | Transfer tokens (`MsgSend`)                             |
| `delegateTokens(delegator, validator, amount, fee, memo?)`   | Delegate to a validator (`MsgDelegate`)                 |
| `undelegateTokens(delegator, validator, amount, fee, memo?)` | Undelegate from a validator (`MsgUndelegate`)           |
| `withdrawRewards(delegator, validator, fee, memo?)`          | Withdraw staking rewards (`MsgWithdrawDelegatorReward`) |

These convenience methods accept the same three fee forms — `"auto"`, a number multiplier, or an explicit `StdFee`.

## Next Steps

<CardGroup cols={2}>
  <Card title="Building Messages" icon="hammer" href="/cosmjs/v0.38.x/guides/transactions/building-messages">
    Construct message objects for token transfers, staking, and multi-message transactions.
  </Card>

  <Card title="Simulating Gas" icon="gauge" href="/cosmjs/v0.38.x/guides/transactions/simulating-gas">
    Estimate gas with auto fees, manual simulation, or explicit fee objects.
  </Card>

  <Card title="Signing & Broadcasting" icon="paper-plane" href="/cosmjs/v0.38.x/guides/transactions/signing-broadcasting">
    Sign and broadcast transactions, or separate the two steps for advanced workflows.
  </Card>

  <Card title="Waiting for Confirmation" icon="clock" href="/cosmjs/v0.38.x/guides/transactions/confirmation">
    Configure polling timeouts and handle transactions that take too long.
  </Card>

  <Card title="Error Handling" icon="triangle-exclamation" href="/cosmjs/v0.38.x/guides/transactions/error-handling">
    Handle CheckTx rejections, execution failures, and timeouts.
  </Card>

  <Card title="Events & Lookups" icon="magnifying-glass" href="/cosmjs/v0.38.x/guides/transactions/events-and-lookups">
    Read transaction events and look up past transactions by hash or query.
  </Card>
</CardGroup>