> ## Documentation Index
> Fetch the complete documentation index at: https://apidocs.taxwire.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Quickstart

> Getting started with the Taxwire API

## Authentication

To use the Taxwire API there is minimal setup or overhead. All you need is an authentication header `X-API-Key` (see [authentication](/api-reference/authentication) for details).

## API versioning

To ensure best result, we also recommend you use a version header so you can be confident about what the response will be.
Visit the [versioning](/api-reference/versioning) page for more information.

## Quickstart

You are now ready to make your first API request.
Here is a simple, yet complete example of how to make a calculation request.

All you need is to replace the header `X-API-Key` and `Taxwire-Version` with real values.

<CodeGroup>
  ```shell cURL theme={null}
  curl -X POST \
    --url https://api.taxwire.com/calculations \
    --header 'Content-Type: application/json' \
    --header 'X-API-Key: REPLACE_WITH_YOUR_API_KEY' \
    --header 'Taxwire-Version: hydrogen.2025-04-15' \
    --data '{
      "line_items": [
        {
          "quantity": "1",
          "unit_price": "100",
          "customer": {
            "address": {
              "line1": "123 Main St",
              "city": "San Francisco",
              "state": "CA",
              "country": "US",
              "postal_code": "94105"
            }
          }
        }
      ]
    }'
  ```

  ```python Python theme={null}
  import requests

  url = "https://api.taxwire.com/calculations/"
  headers = {
      "X-API-Key": "REPLACE_WITH_YOUR_API_KEY",
      "Taxwire-Version": "hydrogen.2025-04-15",
      "Content-Type": "application/json",
  }
  payload = {
      "line_items": [
          {
              "quantity": "1",
              "unit_price": "100",
              "customer": {
                  "address": {
                      "line1": "123 Main St",
                      "city": "San Francisco",
                      "state": "CA",
                      "country": "US",
                      "postal_code": "94105",
                  }
              }
          }
      ]
  }
  response = requests.request("POST", url, json=payload, headers=headers)
  response.json()
  ```

  ```javascript JavaScript theme={null}
  const options = {
    method: "POST",
    headers: {
      "X-API-Key": "REPLACE_WITH_YOUR_API_KEY",
      "Taxwire-Version": "hydrogen.2025-04-15",
      "Content-Type": "application/json",
    },
    body: JSON.stringify({
      line_items: [
        {
          quantity: "1",
          unit_price: "100",
          customer: {
            address: {
              line1: "123 Main St",
              city: "San Francisco",
              state: "CA",
              country: "US",
              postal_code: "94105",
            }
          }
        }
      ]
    }),
  };

  fetch("https://api.taxwire.com/calculations/", options)
    .then((response) => response.json())
    .then((response) => console.log(response))
    .catch((err) => console.error(err));

  ```
</CodeGroup>

It's that easy!

Want to get down to the nitty gritty? Check out our more detailed guides or individual API reference pages.