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

# Link Project Defaults to Calculators

> Use reference IDs to link project defaults into calculators, and pull in custom loads you defined earlier.

Once your defaults are set, you can link them directly into specific calculators. This video demonstrates how reference IDs work and how to pull in the custom loads you defined earlier, using the wood beam floor joist as the example.

To link your data:

<Step title="Open a calculator">
  Open any calculator (e.g., Wood Beam). You will see fields referencing **Project Defaults** with a reference ID (e.g., `l_b`).
</Step>

<Step title="Verify dynamic updates" stepNumber={2}>
  If you change a value in Project Defaults (like bearing length), it automatically updates inside the calculator.
</Step>

<Step title="Link custom loads" stepNumber={3}>
  In your load inputs, select **Link to Project Defaults** to pull in specific items, such as the mechanical unit defined in [Setting Up Project Defaults and Site Parameters](/docs/projects/project-defaults/setting-up-project-defaults-site-parameters).
</Step>

<iframe src="https://fast.wistia.com/embed/medias/epup91nzwf" title="How to Link Project Defaults to Calculators in Calcs.com" className="w-full h-96 rounded-xl" allowFullScreen allow="autoplay; fullscreen" />