> ## 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.

# Gas Estimation Errors

> Errors from gas price configuration and transaction simulation.

These errors occur when gas pricing is misconfigured or when transaction simulation fails. They are most commonly encountered when using `"auto"` fee estimation.

## Missing Gas Price

Thrown when using `"auto"` fee without setting a gas price:

```
"Gas price must be set in the client options when auto gas is used."
```

Fix: pass `gasPrice` when creating the signing client:

```typescript theme={"system"}
const client = await SigningStargateClient.connectWithSigner(endpoint, signer, {
  gasPrice: GasPrice.fromString("0.025uatom"),
});
```

## Simulation Failure

`simulate` throws if the signer address is not found in the wallet:

```
"Failed to retrieve account from signer"
```

If the simulation itself fails (e.g. message validation errors), the underlying
gRPC error propagates.