Skip to main content

​
Current API version

hydrogen.2025-04-15

​
Version naming

We use a date & human-readable name based semantic versioning for our API. This means that we increment the named version when we make breaking changes to the API. Version format: named_version.YYYY-MM-DD Example: hydrogen.2025-03-21 
hydrogen.2025-03-21 -> hydrogen.2025-04-22 ==> No breaking changes
hydrogen.2025-03-21 -> helium.2025-04-22 ==> Breaking changes
In order to ensure you get a response format that you expect, we recommend that you pass a version header to your API calls.

Warning

If you do not provide a version header, you will get the latest version of the API which could include breaking changes since the last time you called the API.
A version header Taxwire-Version is expected in the following format: 
curl --request POST \
  --url https://api.taxwire.com/calculations \
  --header 'Content-Type: application/json' \
  --header 'Taxwire-Version: hydrogen.2025-04-15' \
  --header 'X-API-Key: YOUR_API_KEY' \
  --data '{....SOME BEAUTIFUL JSON....}'