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

# Configure Capacity Modifier Fields

> Reduce effective resource capacity using two percentage-based modifier fields on Team work items, enabling accurate workload calculations for partially allocated resources in Nextedy GANTT.

export const LastReviewed = ({date}) => {
  if (!date) return null;
  const formatted = new Date(`${date}T00:00:00Z`).toLocaleDateString("en-US", {
    year: "numeric",
    month: "long",
    day: "numeric",
    timeZone: "UTC"
  });
  return <p className="mt-10 text-sm text-gray-400 dark:text-zinc-500 not-prose">
      Last reviewed on {formatted}
    </p>;
};

## Prerequisites

* Working calendars enabled in the Gantt widget (see [Set Up Work Item Calendars](/gantt/guides/calendars/work-item-calendar))
* Team assignments configured with the appropriate work item type
* Access to **Administration > Configuration Properties**

<Steps>
  <Step title="Define the Modifier Fields">
    Capacity modifiers use two custom fields on your Team work items. Each field holds a percentage value (0-100) representing a capacity reduction.

    Add the following properties under **Administration > Configuration Properties**:

    ```
    nextedy.gantt.capacityModifierAField=capacityModA
    nextedy.gantt.capacityModifierBField=capacityModB
    ```

    Replace `capacityModA` and `capacityModB` with the actual field IDs on your Team work items.

    | Property                                       | Purpose                                                     | Example Value  |
    | ---------------------------------------------- | ----------------------------------------------------------- | -------------- |
    | `nextedy.gantt.capacityModifierAField`         | Field ID for modifier A (permanent reduction)               | `capacityModA` |
    | `nextedy.gantt.capacityModifierBField`         | Field ID for modifier B (time-limited reduction)            | `capacityModB` |
    | `nextedy.gantt.capacityModifierBFieldDayLimit` | Number of days from today within which modifier B is zeroed | `30`           |
  </Step>

  <Step title="Understand the Capacity Formula">
    The Gantt calculates effective capacity using both modifiers:

    ```
    effectiveCapacity = base * (1 - (capModA + capModB) / 100)
    ```

    For example, if a resource has 8 working hours per day, modifier A is 25%, and modifier B is 10%:

    ```
    effectiveCapacity = 8 * (1 - (25 + 10) / 100) = 8 * 0.65 = 5.2 hours
    ```

    <Frame>
      <img src="https://mintcdn.com/none-17b4493f/DDjWgCW2DWY5biNv/gantt/diagrams/guides/calendars/capacity-modifier-fields/diagram-1.svg?fit=max&auto=format&n=DDjWgCW2DWY5biNv&q=85&s=511d624dcbc2e6d4bb6c9d72b7c85dfc" alt="diagram" style={{ maxWidth: "780px", width: "100%" }} width="780" height="60" data-path="gantt/diagrams/guides/calendars/capacity-modifier-fields/diagram-1.svg" />
    </Frame>
  </Step>

  <Step title="Configure the Modifier B Day Limit">
    Modifier B includes a time-horizon feature: within a specified number of days from today, modifier B is zeroed out. This allows you to model scenarios where a future capacity reduction is planned but should not affect near-term scheduling.

    ```
    nextedy.gantt.capacityModifierBFieldDayLimit=30
    ```

    With this setting, modifier B is applied only to dates more than 30 days in the future. For dates within the next 30 days, only modifier A affects the capacity calculation.

    <Tip title="Using Modifiers for Different Scenarios">
      Use modifier A for permanent capacity reductions (such as part-time allocation to the project) and modifier B for planned future changes (such as an upcoming role change or project transition). The day-limit ensures near-term planning uses current capacity while long-term planning reflects the expected change.
    </Tip>
  </Step>

  <Step title="Enable Team Capacity Modifiers">
    To activate team-level capacity modifiers, add this property:

    ```
    nextedy.gantt.useTeamCapacityModifiers=true
    ```

    When enabled, team modifiers (fields A and B) reduce effective resource capacity in the resource view. The modifiers are read from the Team work item that each user is assigned to.

    <Warning title="Field Must Exist on Work Items">
      The fields specified by `nextedy.gantt.capacityModifierAField` and `nextedy.gantt.capacityModifierBField` must exist as custom fields on the Team work item type. If the fields are missing, the modifiers are silently ignored and capacity is calculated without reduction.
    </Warning>
  </Step>

  <Step title="Enable Working Calendars in the Widget">
    Open the Gantt widget parameters and navigate to **Working Calendars**:

    1. Set **Use Working Calendar** to **Yes**
    2. Set **Load User Calendars** to **Yes**
    3. Set **Load Team Assignments** to **Yes**

    The capacity modifiers are applied during calendar building, combining the base working hours from the user's calendar with the percentage reductions from the user's Team work item.

    <Warning title="Multiple Assignments Stack Additively">
      When a user has multiple team assignment work items, the capacity contributions from all assignments are summed together with the user's calendar to build their effective daily capacity. Keep the total across all assignments realistic (typically not exceeding 100%) -- additive stacking can otherwise overstate a user's availability and hide real overallocation.
    </Warning>
  </Step>
</Steps>

## Verify

You should now see that resource view allocation markers reflect the reduced capacity for users with modifier fields set on their team assignments. A resource with a 25% modifier A shows 6 hours of available capacity per day (instead of 8), and tasks assigned to that resource display higher utilization percentages accordingly.

## See Also

* [Set Up Work Item Calendars](/gantt/guides/calendars/work-item-calendar)
* [Customize Working Hours per Resource](/gantt/guides/calendars/working-hours-per-resource)
* [Set Up the Resource View](/gantt/guides/resources/resource-view)
* [Configure Resource Fields](/gantt/guides/resources/resource-field-configuration)
* [Set Up Team Assignments Gantt](/gantt/guides/resources/team-assignments-gantt)

<LastReviewed date="2026-06-24" />