Django CBV vs FBV: Complete Comparison of Class and Function-Based Views

Last updated: April 2026 · AnomixLabs Technical Team

CBVs and FBVs are not rivals, but complements. A developer proficient in Django will use both—choosing the right tool for the job.

1. Function-Based Views (FBV)

An FBV is a view written as a Python function. It handles GET and POST requests by checking request.method. Its strengths lie in its simplicity and readability:

from django.shortcuts import render, get_object_or_404, redirect
from django.contrib.auth.decorators import login_required
from .models import Article
from .forms import ArticleForm

@login_required
def article_create(request):
    if request.method == 'POST':
        form = ArticleForm(request.POST)
        if form.is_valid():
            article = form.save(commit=False)
            article.author = request.user
            article.save()
            return redirect(article)
    else:
        form = ArticleForm()
    return render(request, 'article_form.html', {'form': form})

2. Class-Based Views (CBV) — Generic Views

CBVs leverage Django's class hierarchy. Generic views provide standard CRUD patterns with minimal code:

from django.views.generic import (
    ListView, DetailView, CreateView, UpdateView, DeleteView
)
from django.contrib.auth.mixins import LoginRequiredMixin
from django.urls import reverse_lazy

class ArticleListView(ListView):
    model = Article
    template_name = 'article_list.html'
    context_object_name = 'articles'
    paginate_by = 10
    ordering = ['-created_at']

class ArticleDetailView(DetailView):
    model = Article
    slug_field = 'slug'

class ArticleCreateView(LoginRequiredMixin, CreateView):
    model = Article
    fields = ['title', 'content']
    login_url = '/login/' # Assuming '/login/' is the login URL

    def form_valid(self, form):
        form.instance.author = self.request.user
        return super().form_valid(form)

class ArticleDeleteView(LoginRequiredMixin, DeleteView):
    model = Article
    success_url = reverse_lazy('article_list')

3. Overriding get_queryset and get_context_data

class ArticleListView(ListView):
    model = Article

    def get_queryset(self):
        # Fetch only published articles, avoiding N+1
        return Article.objects.filter(
            is_published=True,
        ).select_related('author', 'category')\
         .prefetch_related('tags')

    def get_context_data(self, **kwargs):
        ctx = super().get_context_data(**kwargs)
        ctx['total_count'] = self.get_queryset().count()
        ctx['categories'] = Category.objects.all()
        return ctx

4. The Mixin MRO Trap

When using multiple mixins, Python's Method Resolution Order (MRO) is critical. LoginRequiredMixin should always come first:

# CORRECT — LoginRequiredMixin first
class ArticleCreateView(LoginRequiredMixin, CreateView):
    ...

# INCORRECT — MRO conflict, login redirect won't work
class ArticleCreateView(CreateView, LoginRequiredMixin):
    ...

# To see the order:
print(ArticleCreateView.__mro__)

5. Writing Custom Mixins

class AuthorRequiredMixin:
    """Mixin that only allows the object's owner to access."""

    def get_object(self):
        obj = super().get_object()
        if obj.author != self.request.user:
            from django.core.exceptions import PermissionDenied
            raise PermissionDenied
        return obj

class ArticleUpdateView(LoginRequiredMixin, AuthorRequiredMixin, UpdateView):
    model = Article
    fields = ['title', 'content']

6. Custom Form Handling with FormView

from django.views.generic.edit import FormView

class SearchView(FormView):
    template_name = 'search.html'
    form_class = SearchForm
    success_url = '.'  # Return to the same page

    def form_valid(self, form):
        query = form.cleaned_data['query']
        # Perform search, save to session, etc.
        return super().form_valid(form)

7. When to Use Which?

8. Writing Tests: FBV vs CBV

from django.test import TestCase, Client
from django.contrib.auth import get_user_model

User = get_user_model()

class ArticleViewTests(TestCase):
    def setUp(self):
        self.user = User.objects.create_user('ali', password='pass')
        self.client = Client()

    def test_list_view(self):
        response = self.client.get('/articles/') # Assuming '/articles/' is the URL for ArticleListView
        self.assertEqual(response.status_code, 200)

    def test_create_requires_login(self):
        response = self.client.get('/articles/new/') # Assuming '/articles/new/' is the URL for ArticleCreateView
        self.assertRedirects(response, '/login/?next=/articles/new/') # Assuming '/login/' is the login URL

    def test_create_logged_in(self):
        self.client.login(username='ali', password='pass')
        response = self.client.get('/articles/new/')
        self.assertEqual(response.status_code, 200)

9. URL Structure Comparison

from django.urls import path
from . import views # Assuming views.py contains the FBV and CBV definitions

urlpatterns = [
    # FBV
    path('new/', views.article_create, name='article_create'),

    # CBV — .as_view() is required
    path('', ArticleListView.as_view(), name='article_list'),
    path('/', ArticleDetailView.as_view(), name='article_detail'), # Assuming slug is used for detail view
    path('/delete/', ArticleDeleteView.as_view(), name='article_delete'), # Assuming slug is used for delete view
]

Summary

Know both approaches and choose based on the situation. CBVs are suitable for standard CRUD, repetitive patterns, and when mixins are needed. FBVs are better for complex business logic, webhooks, and single-function views. Pay attention to MRO order when using mixins—LoginRequiredMixin should always be first. Writing tests is similarly straightforward for both approaches.