# Estimations

We offer several functions to help you estimate costs, including bridging and deployment fees.

## Bridge Costs

To estimate bridge fees and minimum gas limits, we provide the `estimateBridgeFee` function. See below for more information.

<pre class="language-solidity"><code class="lang-solidity">/**
 * @notice Returns estimated minimal amount to pay for bridging and minimal gas limit.
 * @param dstChainId destination chain Id.
 * @param dstGasLimit {redeem} call gas limit on the destination chain.
 * @param customPayloadLength user's additional data length.
 * @param protocolPayload UTS protocol's additional data.
 * @return paymentAmount source chain native currency amount to pay for bridging.
 * @return dstMinGasLimit destination chain minimal {redeem} call gas limit.
 */
<strong>function estimateBridgeFee(
</strong>    uint256 dstChainId,
    uint64 dstGasLimit,
    uint16 customPayloadLength,
    bytes calldata protocolPayload
) public view virtual returns(uint256 paymentAmount, uint64 dstMinGasLimit)
</code></pre>

<table><thead><tr><th>Name</th><th>Meaning</th></tr></thead><tbody><tr><td><pre><code>dstChainId
</code></pre></td><td>Destination chain Id</td></tr><tr><td><pre><code>dstGasLimit
</code></pre></td><td>Destination gas limit</td></tr><tr><td><pre><code>customPayloadLength
</code></pre></td><td>Length of your custom payload</td></tr><tr><td><pre><code>protocolPayload 
</code></pre></td><td>UTS protocol payload</td></tr></tbody></table>

## Gas Limits

The UTS Router provides a function called `dstMinGasLimit` which returns the amount of gas required to execute the {redeem} function on the destination chain.

```solidity
/**
* @notice Returns the amount of gas required to execute {redeem} function on the destination chain.
* @param dstChainId destination chain Id.
* @return dstMinGasLimitAmount the amount of gas required to execute {redeem} function on the provided {dstChainId}.
*/
function dstMinGasLimit(
    uint256 dstChainId
) public view returns(uint64 dstMinGasLimitAmount)
```

## Deployment Costs

If you want to perform a cross-chain deploying using our `UTSDeploymentRouter`, you can use the `estimateDeploy` function to estimate the separated payments required for sending crosschain deployment requests in the payment token. The function will return the fees you need to pay in `PAYMENT_TOKEN.`

```solidity
/**
 * @notice Estimates the separated payments required for send crosschain deployment requests in the {PAYMENT_TOKEN}.
 * @param dstTokenChainIds destination chain Ids for {UTSToken} deployments.
 * @param dstConnectorChainIds destination chain Ids for {UTSConnector} deployments.
 * @return tokenPaymentAmount array of estimated payment amount in the {PAYMENT_TOKEN} for each {dstChainId}.
 * @return connectorPaymentAmount array of estimated payment amount in the {PAYMENT_TOKEN} for each {dstChainId}.
 * @return totalPaymentAmount estimated total payment amount in the {PAYMENT_TOKEN}.
 */
function estimateDeploy(
    uint256[] calldata dstTokenChainIds,
    uint256[] calldata dstConnectorChainIds
) external view returns(
    uint256[] memory tokenPaymentAmount, 
    uint256[] memory connectorPaymentAmount, 
    uint256 totalPaymentAmount
)
```

<table><thead><tr><th>Name</th><th>Meaning</th></tr></thead><tbody><tr><td><pre><code>dstTokenChainIds
</code></pre></td><td>Array of chain ids where UTS Tokens will be deployed</td></tr><tr><td><pre><code>dstConnectorChainIds
</code></pre></td><td>Array of chain ids where UTS Connectors will be deployed</td></tr></tbody></table>

## Deployment Costs in Native Currency

If you want to perform a cross-chain deploying using our `UTSDeploymentRouter`, you can use the `estimateDeployNative` function to estimate the separated payments required for sending crosschain deployment requests in the payment token. The function will return the fees you need to pay in native currency.

```solidity
/**
 * @notice Estimates the separated payments required for send crosschain deployment requests in native currency.
 * @param dstTokenChainIds destination chain Ids for {UTSToken} deployments.
 * @param dstConnectorChainIds destination chain Ids for {UTSConnector} deployments.
 * @return tokenPaymentAmountNative array of estimated payment amount in native currency for each {dstChainId}.
 * @return connectorPaymentAmountNative array of estimated payment amount in native currency for each {dstChainId}.
 * @return totalPaymentAmountNative estimated total payment amount in native currency.
 */
function estimateDeployNative(
    uint256[] calldata dstTokenChainIds,
    uint256[] calldata dstConnectorChainIds
) external view returns(
    uint256[] memory tokenPaymentAmountNative, 
    uint256[] memory connectorPaymentAmountNative, 
    uint256 totalPaymentAmountNative
)
```