> ## 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.

# Find Out Which Plan Unlocks a Feature

> Why a calculator tab or input is grayed out or locked, and what you see when a feature is plan-gated.

Some Calcs.com calculators and features are only available on specific plans. If a calculator tab or input is grayed out or shows a lock or upgrade prompt mid-workflow, the most likely reason is that the feature lives on a higher plan than the one you're currently on. For example, the **concrete beam design tab** is part of our [**Pro plan**](https://calcs.com/pricing), so it won't be accessible on a lower plan.

## What you see when a feature is plan-gated

When you open a calculator or tab that isn't included in your current plan, Calcs.com doesn't silently fail: you'll see an **upgrade prompt** or a locked-tab indicator that names the plan required to unlock it. Inputs in a gated tab are typically disabled, and any linked outputs flowing into that tab won't compute until the plan is upgraded.

If you've opened a project shared with you that uses calculators outside your plan, those calculators will still display their existing inputs and results in read-only form, but you won't be able to edit them or run new analyses against them until you upgrade.

## Related

* [Compare Plans](/docs/plans/about/choose-a-plan#compare-plans)
* [Upgrade Your Plan](/docs/plans/billing/upgrade-your-plan)