[Canonical page](<https://docs.dhtmlx.com/planning-engine/java/api/data/time-unit/>)
[Full documentation index](<https://docs.dhtmlx.com/planning-engine/llms.txt>)


# TimeUnit

The unit that a task's duration and a link's lag are counted in. [`SchedulingConfig.durationUnit`](<https://docs.dhtmlx.com/planning-engine/java/api/data/scheduling-config.md#durationunit>) sets the project default. A task overrides it with [`TaskData.durationUnit`](<https://docs.dhtmlx.com/planning-engine/java/api/data/task-data.md>), and a link with [`LinkData.lagUnit`](<https://docs.dhtmlx.com/planning-engine/java/api/data/link-data.md#lagunit>).

## Declaration

```java
package org.dhtmlx.plen;

public enum TimeUnit { MINUTE, HOUR, DAY }
```

## Values

| Value | Description |
|---|---|
| `MINUTE` | Working minutes. Amounts are rounded to whole minutes when a date is placed. |
| `HOUR` | Working hours of 60 minutes. Amounts are rounded to whole minutes when a date is placed. |
| `DAY` | Working days. A working day of any length counts as one day, and a placed date keeps its time of day. Amounts are rounded to whole days when a date is placed. |

There are no week, month or year values.

A duration or lag in these units is working time: non-working time on the calendar doesn't count. [`TaskData.levelingDelay`](<https://docs.dhtmlx.com/planning-engine/java/api/data/task-data.md>) and [`Pause`](<https://docs.dhtmlx.com/planning-engine/java/api/data/pause.md>) positions and lengths use the same unit as elapsed time, where `DAY` means 24 hours.

## Where it's used

| Member | Type | Meaning |
|---|---|---|
| [`SchedulingConfig.durationUnit`](<https://docs.dhtmlx.com/planning-engine/java/api/data/scheduling-config.md#durationunit>) | `TimeUnit` | Project default. Default: `DAY`. |
| [`TaskData.durationUnit`](<https://docs.dhtmlx.com/planning-engine/java/api/data/task-data.md>) | `TimeUnit` | Unit of the task's `duration`, `levelingDelay` and `pauses`. `null` uses the project default. |
| [`LinkData.lagUnit`](<https://docs.dhtmlx.com/planning-engine/java/api/data/link-data.md#lagunit>) | `TimeUnit` | Unit of the link's `lag`. `null` uses the project default. |
| [`LinkAdd.lagUnit`](<https://docs.dhtmlx.com/planning-engine/java/api/changes/link-add.md>) | `TimeUnit` | Same as `LinkData.lagUnit`, for a link added with `apply`. |
| [`LinkUpdate.lagUnit`](<https://docs.dhtmlx.com/planning-engine/java/api/changes/link-update.md>) | [`Patch<TimeUnit>`](<https://docs.dhtmlx.com/planning-engine/java/api/changes/patch.md>) | Changes the unit of an existing link's lag. |

In JSON the values are spelled `"minute"`, `"hour"` and `"day"`. [`Decode`](<https://docs.dhtmlx.com/planning-engine/java/api/json/decode.md>) rejects any other spelling. See [Exchange JSON with a client](<https://docs.dhtmlx.com/planning-engine/java/how-to/exchange-json-with-a-client.md>).

## Example

The project counts in days, task 2 counts in hours, and the link's lag is in minutes:

```java
import java.util.List;
import org.dhtmlx.plen.*;

public class TimeUnitExample {
  public static void main(String[] args) throws Exception {
    Moment monday = Moment.fromYmdHm(2026, 4, 6, 8, 0);

    ProjectData data = new ProjectData()
        .withConfig(new SchedulingConfig().withDurationUnit(TimeUnit.DAY))
        .withTasks(List.of(
            new TaskData(Id.num(1)).withStartDate(monday).withDuration(2.0),
            new TaskData(Id.num(2))
                .withStartDate(monday)
                .withDuration(6.0)
                .withDurationUnit(TimeUnit.HOUR)))
        .withLinks(List.of(
            new LinkData()
                .withId(Id.str("a"))
                .withSource(Id.num(1))
                .withTarget(Id.num(2))
                .withLag(30.0)
                .withLagUnit(TimeUnit.MINUTE)));

    ScheduleResult result = Engine.schedule(data, new SolveOptions());
    for (Mutation update : result.updates) {
      System.out.println(update.id + ": " + update.startDate + " - " + update.endDate);
    }
  }
}
```

Output:

```
2: 2026-04-08 08:30 - 2026-04-08 15:30
```

Task 1 takes two working days, Monday and Tuesday. Task 2 starts 30 working minutes after that and runs six working hours on the default 08:00-12:00, 13:00-17:00 calendar.

## Related

- [`TaskData`](<https://docs.dhtmlx.com/planning-engine/java/api/data/task-data.md>) - the duration unit of a task
- [`LinkData`](<https://docs.dhtmlx.com/planning-engine/java/api/data/link-data.md#lagunit>) - the lag unit of a link
- [`SchedulingConfig.durationUnit`](<https://docs.dhtmlx.com/planning-engine/java/api/data/scheduling-config.md#durationunit>) - the project default
- [Durations and units](<https://docs.dhtmlx.com/planning-engine/java/scheduling/project-data.md#durations-and-units>) - how units convert to working time