> For the complete documentation index, see [llms.txt](https://docs.arrng.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.arrng.io/getting-a-cost-estimate.md).

# Getting a cost estimate

The arrng API will return a live estimate of the native token (e.g. ETH) you need to send with requests to arrng.

Access the getCost end point using your preferred method:

```
https://api.arrng.io/getCost?chain=1&quantity=1&complexity=1 
```

* Chain. Set this to the chain you are using (e.g. 1 for ETH mainnet)
* Quantity. Set this to the number of random numbers you are requesting.
* Complexity. Your estimate of the complexity of work being done in the method that recieves the RNG. For example:
  * If you are just storing the RNG that would be low complexity and therefore a value of 1. 
  * If you are storing the RNG, setting a boolean and doing some light maths that would be a value of 2.
  * If you are doing something more complex, like minting tokens and updating multiple balances, that would be 3.

The API will provide a json response with the amount of native token to be sent on the call, for example:

```
{"nativeToken":0.0048}
```