Inline Editing in Django Admin

Inline allows you to edit related objects directly on the parent object’s page.

TabularInline

from django.contrib import admin
from .models import Project, Task

class TaskInline(admin.TabularInline):
    model = Task
    extra = 1  # number of empty forms
    fields = ['title', 'status', 'priority']

@admin.register(Project)
class ProjectAdmin(admin.ModelAdmin):
    inlines = [TaskInline]

Result: a table of tasks will appear on the project page.

StackedInline

class TaskInline(admin.StackedInline):
    model = Task
    extra = 0
    fields = ['title', 'description', 'status']
    show_change_link = True  # link to the edit page

StackedInline displays each object as a block; TabularInline displays each object as a table row.

Inline Settings

class TaskInline(admin.TabularInline):
    model = Task
    extra = 0
    max_num = 10          # maximum number of objects
    min_num = 1           # minimum
    can_delete = True
    readonly_fields = ['created_at']

extra = 0 — Remove Empty Forms

By default extra = 3 — Django shows three empty forms for adding new objects. This often clutters the interface. Set extra = 0 when users rarely add related objects:

class TaskInline(admin.TabularInline):
    model = Task
    extra = 0  # no empty forms — add via the "Add another" button

can_delete = False — Prevent Deletion

If deleting related objects through Admin is undesirable — disable the delete checkboxes:

class TaskInline(admin.TabularInline):
    model = Task
    extra = 0
    can_delete = False  # removes the "Delete" checkbox column

Useful when tasks should only be deleted through a separate interface or via soft delete.

max_num — Limit the Count

max_num limits how many related objects can be added through the inline. Once the limit is reached, the “Add another” button disappears:

class TaskInline(admin.TabularInline):
    model = Task
    extra = 0
    max_num = 5  # no more than 5 tasks per project through this interface

readonly_fields in Inline

Works the same as in a regular ModelAdmin. Useful for fields like created_at, slug, or computed values:

class TaskInline(admin.TabularInline):
    model = Task
    extra = 0
    fields = ['title', 'status', 'created_at']
    readonly_fields = ['created_at']

Fields listed in readonly_fields must also appear in fields, otherwise they won’t be shown.

Inline for ManyToMany

class TagInline(admin.TabularInline):
    model = Task.tags.through  # intermediate table
    extra = 1

Common Mistake: Wrong Direction of the Relation

Inline is registered on the parent model — the one that the other model’s ForeignKey points to.

class Task(models.Model):
    project = models.ForeignKey(Project, on_delete=models.CASCADE)

Here Task points to Project. So TaskInline goes inside ProjectAdmin — not the other way around:

# CORRECT: TaskInline inside ProjectAdmin
@admin.register(Project)
class ProjectAdmin(admin.ModelAdmin):
    inlines = [TaskInline]

# WRONG: can't put ProjectInline in TaskAdmin with FK on Project
# Django will raise an error: the inline model must have a FK on the parent model

If you need to edit the project from the task page — use raw_id_fields or autocomplete_fields, but not an inline in the reverse direction.