--- url: /reference/task-ids.md description: >- How a list numbers its tasks: series, patterns, padding and what happens when you change them. --- # Task IDs and series This page lists how Hule gives tasks their Task IDs, such as `BT-0042`, and what changes when you edit a list's numbering. To change it step by step, see [Set up a list](/guides/set-up-a-list#task-id-prefix-and-numbering). ## Terms | Term | Meaning | |---|---| | **Task ID** | A task's short key, such as `BT-0042`. It shows on the task while the list's [**Task Number**](/guides/set-up-a-list#turn-features-on-or-off) feature is on, and you can [search](/guides/find-anything) for it. | | **Task series** | A counter that issues Task IDs. A list draws from one series; several lists can share one. | | **Pattern** | The series' template for a Task ID: text around one number placeholder, such as `BT-{0000}`. | | **Next key** | The Task ID the next new task on the series will get. | ## Pattern syntax A pattern has exactly one placeholder: zeros in braces. The number of zeros is the least number of digits; longer numbers grow past it. The text before and after the placeholder stays as typed. | Pattern | Task IDs it gives | |---|---| | `BT-{0}` | `BT-1`, `BT-2` … `BT-10` | | `BT-{0000}` | `BT-0001` … `BT-9999`, then `BT-10000` | | `HOME-{000}` | `HOME-001`, `HOME-002` … | | `Q3-{00}-WEB` | `Q3-01-WEB`, `Q3-02-WEB` … | * A pattern is at most 32 characters long. * The text around the placeholder can't contain `{` or `}`, and there is only one placeholder. * A pattern that breaks these rules shows "Use one number placeholder, e.g. BT-{0000}" and can't be applied. ## Default series of a new list Unless you pick an existing series, a new list gets a series of its own. In the form that **New list** opens ([Organize folders and lists](/guides/organize-folders-and-lists)), the **Features** step holds a **Task ID** section: | Choice | What the list gets | |---|---| | **Custom Task IDs** off | A new series with a prefix taken from the list's name and the pattern `-{0}` | | **Custom Task IDs** on, **New series** | A new series with the pattern you type; the form shows the first key | | **Custom Task IDs** on, **Use existing** | An existing series of the [workspace](/guides/organize-folders-and-lists) that a list you can open uses, shared with the lists already on it | The prefix comes from the list's name: * several words: the first letter or digit of each word; * one word: its first three letters or digits; * in capitals, at most three characters; * a name with no letters or digits: `T`. | List name | Default pattern | First Task ID | |---|---|---| | Backend Tasks | `BT-{0}` | `BT-1` | | Sprint 1 | `S1-{0}` | `S1-1` | | Design | `DES-{0}` | `DES-1` | | A name with no letters or digits, such as `!!!` | `T-{0}` | `T-1` | ## Task series settings In the list's **Configure** window, the **Task series** page ([Set up a list](/guides/set-up-a-list#task-id-prefix-and-numbering)) holds: | Setting | What it does | |---|---| | **Series** | Which counter the list draws Task IDs from. The menu lists, by pattern, the workspace's series used by a list [you can open](/reference/permissions-and-access), plus **New series…** | | **Pattern** | The pattern of the list's current series, or of a new one. Its line shows the next Task ID, such as `Next key: HOME-013`. Hidden when you pick another list's series | | **Apply series** | Saves the change. For an existing series, the line next to it says how many lists and tasks share it, such as **Shared with 3 lists · 120 tasks**. With **New series…**, it stays unavailable until the pattern differs from the current one | ::: warning Edit access needed Changing a list's series or pattern needs **Edit** access to the list and **Update** in the **Lists** block of your permission set, such as **List/Folder manager** or **Admin**. See [Permissions and access](/reference/permissions-and-access). ::: ## Numbering rules ### Counting and patterns **The counter only goes up.** The first task on a series gets 1, and each new task takes the next number. Numbers of deleted or moved-out tasks are not reused, so gaps are normal. Example: on `HOME-{000}`, you delete `HOME-012`; the next task is still `HOME-013`. **A new pattern applies to new tasks only.** Existing tasks keep the Task IDs they were given. Example: you change `HOME-{000}` to `H-{0}` after 12 tasks; the old ones stay `HOME-001` … `HOME-012`, and the next task is `H-13`. **Lists on one series share its counter.** Tasks get the next number of the series whichever list they are created in. Example: `Sprint 1` and `Sprint 2` share `SP-{0}`; `Sprint 1` has `SP-1` to `SP-40`, so the first task in `Sprint 2` is `SP-41`. **Editing a shared series' pattern changes it for every list on it.** When more than one list uses the series and you change its pattern, Hule shows a warning under **Pattern**: the new pattern applies to every list on the series, and only tasks created after the change use it. Example: three lists share `SP-{0}` and the last task was `SP-40`; after you change it to `SPR-{0}`, the next task in any of the three is `SPR-41`. **Task Number off hides the Task ID, it doesn't stop it.** With the **Task Number** feature off ([Set up a list](/guides/set-up-a-list#turn-features-on-or-off)), tasks still get Task IDs; they are only hidden until you turn **Task Number** back on. ### Switching series **Picking another series joins its numbering.** When you [pick another series](/guides/set-up-a-list#task-id-prefix-and-numbering) for a list, the list takes that series' pattern and counter. Its existing tasks keep their Task IDs. Example: `Home` (last task `HOME-013`) picks `SP-{0}`, whose last task was `SP-40`; the next task in `Home` is `SP-41`, and the old ones stay `HOME-…`. **New series… starts at 1.** The list leaves its old series, and its next task gets number 1 of the new pattern. Example: `Home` switches from `HOME-{000}` to a new series `H-{00}`; the next task is `H-01`. **Patterns are not checked for repeats.** A new series always starts at 1, even when its pattern is the same as another series' pattern, including the one this list used before. Its Task IDs then repeat ones that already exist. ::: warning Repeated Task IDs Pick a pattern no other series uses, such as `HOME2-{000}`. ::: **Default prefixes can repeat.** Two lists whose names give the same prefix get the same default pattern and both issue the same Task IDs. Example: `Backend Tasks` and `Budget Tracking` both get `BT-{0}`, and both issue `BT-1`. Give one of them its own pattern, or [put both on one series](/guides/set-up-a-list#task-id-prefix-and-numbering). **A series no list uses any more is removed.** When the last list leaves a series, it disappears from the **Series** menu, and its tasks keep their Task IDs. ### Moving and copying tasks **Moving a task to a list on another series gives it a new Task ID.** The task and all its [subtasks](/guides/break-down-with-subtasks) take the next numbers of the destination's series, and the old Task IDs no longer find them. A task keeps its Task ID only when the destination list is on the series that gave it that ID. A task keeps the series that numbered it, even after its list switches series. Moving it to any list on another series, including its list's new one, gives it a new Task ID. This applies to one task ([Create and edit tasks](/guides/create-and-edit-tasks#task-menu-duplicate-move-delete)) and to many ([Edit tasks in bulk](/guides/edit-tasks-in-bulk)). Example: `HOME-013` with two subtasks moves to a list on `SP-{0}` whose last task was `SP-40`; they become `SP-41`, `SP-42` and `SP-43`. ::: danger A move can't restore a Task ID Links that carry the old Task ID, such as `/tasks/HOME-013` in a chat or a commit message, no longer find a moved task. Mentions inside Hule keep working. Moving it back gives it another new number, not its old Task ID. ::: **Copies are new tasks.** A [duplicated task](/guides/create-and-edit-tasks#task-menu-duplicate-move-delete), and each new task a [recurring task](/guides/set-up-recurring-tasks) creates, gets the next Task ID of its list's series. Example: duplicating `HOME-005` when the last task was `HOME-013` gives `HOME-014`. **A duplicated folder's lists start new series.** Each list in the copy gets a series of its own with the pattern from its name, starting at 1, even if the original list used a custom or shared series ([Duplicate a folder](/guides/organize-folders-and-lists#duplicate-a-folder)). Example: the copy of `Sprint 1` on `SP-{0}` gets `S1-{0}`, and its first task is `S1-1`. ## Search by Task ID Type the Task ID in search ([Find anything](/guides/find-anything)): ```text HOME-013 ``` An exact Task ID comes first in its workspace's results. Case doesn't matter: this also finds `HOME-013`: ```text home-013 ``` ## Related * [Set up a list](/guides/set-up-a-list): change a list's pattern and series step by step. * [Organize folders and lists](/guides/organize-folders-and-lists): create lists and duplicate folders. * [Find anything](/guides/find-anything): search by Task ID. * [Task fields](/reference/task-fields): the other fields a task has. * [Folders inside folders](/concepts/hierarchy): how workspaces, folders and lists nest.