Nested routes with folders in NextJS - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the purpose of using folders for nested routes in Next.js?

Folders help organize pages into a clear hierarchy, making nested routes easy to manage and understand. Each folder represents a route segment, and files inside define the nested pages.

beginner

How do you create a nested route like /blog/post in Next.js using folders?

Create a folder named blog inside the app directory, then add a file named page.js inside a post folder within blog. This structure maps to the URL /blog/post.

beginner

What file name is required inside a folder to define a page in Next.js App Router?

The file must be named page.js (or page.tsx) inside the folder to define the page component for that route segment.

intermediate

How does Next.js handle dynamic nested routes with folders?

You create folders with square brackets like [id] to mark dynamic segments. For example, app/blog/[id]/page.js maps to /blog/any-value where any-value is dynamic.

intermediate

Why is using nested folders for routes beneficial for large Next.js projects?

It keeps the project organized, makes it easier to find and update pages, and reflects the URL structure clearly, which helps both developers and users understand the app layout.

In Next.js App Router, which file name defines a page inside a folder?

A main.js

B index.js

C page.js

D app.js

Next.js requires a file named page.js inside a folder to define the page component for that route.

How do you create a nested route /shop/products in Next.js?

A Create a file shop-products.js in app folder

B Create files shop.js and products.js in app folder

C Use query parameters in a single page.js

D Create folder shop/products with page.js inside products

Nested folders named shop and products with page.js inside products folder create the /shop/products route.

What folder name syntax is used for dynamic routes in Next.js?

A [param]

B {param}

C (param)

D <param>

Square brackets around a folder or file name, like [param], define dynamic route segments.

If you want a route /profile/settings, where should the page.js file be placed?

A app/profile/settings/page.js

B app/profile.js and app/settings.js

C app/profile-settings/page.js

D app/settings/profile/page.js

Nested folders profile and settings with page.js inside settings folder create /profile/settings route.

Why is nesting routes with folders better than flat files for complex apps?

A It reduces the number of files needed

B It organizes routes clearly and matches URL structure

C It automatically creates API endpoints

D It disables dynamic routing

Nesting folders reflects the URL path and keeps the project organized, which is helpful for complex apps.

Explain how to create a nested route in Next.js using folders. Include how the folder and file names relate to the URL path.

Think about how a folder structure looks like the URL path.

Describe how dynamic nested routes work in Next.js and how you set them up with folders.

Remember the special syntax for dynamic routes.

Practice

1. In Next.js 14 with the App Router, what does placing a page.tsx file inside a nested folder under app/ do?

easy

A. Bundles all pages into a single route regardless of folder structure.

B. Overrides the root page.tsx and disables routing.

C. Creates a nested route matching the folder path in the URL.

D. Automatically generates API endpoints instead of pages.

Solution

1. Step 1: Understand folder structure in Next.js App Router

   Each folder inside app/ represents a route segment in the URL.

2. Step 2: Role of page.tsx in nested folders

   A page.tsx inside a nested folder creates a page for that nested route path.

3. Final Answer:

   Creates a nested route matching the folder path in the URL. -> Option C

4. Quick Check:

   Nested folder + page.tsx = nested route [OK]

Hint: Remember: folder path + page.tsx = nested URL route [OK]

Common Mistakes:

• Thinking nested folders disable routing
• Confusing API routes with page routes
• Assuming all pages merge into one route

2. Which of the following is the correct folder and file structure to create a nested route /dashboard/settings in Next.js App Router?

easy

A. app/dashboard/settings/page.tsx

B. app/dashboard-settings/page.tsx

C. app/dashboard/page.tsx/settings.tsx

D. app/page.tsx/dashboard/settings.tsx

Solution

1. Step 1: Identify folder nesting for nested routes

   Nested routes require nested folders matching the URL segments.

2. Step 2: Match file placement for the nested page

   The page.tsx file must be inside the deepest folder representing the route.

3. Final Answer:

   app/dashboard/settings/page.tsx -> Option A

4. Quick Check:

   Nested folders + page.tsx file = nested route [OK]

Hint: Use nested folders named after URL segments with page.tsx inside [OK]

Common Mistakes:

• Placing page.tsx outside the nested folder
• Using hyphens instead of folders for nested routes
• Misplacing files inside page.tsx instead of folders

3. Given this folder structure inside app/:

app/
  blog/
    [slug]/
      page.tsx
  page.tsx

What URL will render the page inside app/blog/[slug]/page.tsx?

medium

A. /blog/[slug]

B. /blog/*

C. /blog/{slug}

D. /blog/:slug

Solution

1. Step 1: Understand dynamic route syntax in Next.js

   Folders with square brackets like [slug] represent dynamic route segments.

2. Step 2: Translate dynamic folder to URL pattern

   The dynamic segment is represented as :slug in URL patterns, meaning any value matches.

3. Final Answer:

   /blog/:slug -> Option D

4. Quick Check:

   Dynamic folder [slug] = URL param :slug [OK]

Hint: Dynamic folders [name] map to :name in URLs [OK]

Common Mistakes:

• Using literal [slug] in URL
• Confusing dynamic segment syntax
• Assuming wildcard * matches dynamic segments

4. You have this folder structure:

app/
  products/
    page.tsx
  details/
    page.tsx

But navigating to /products/details shows a 404 error. What is the likely cause?

medium

A. The details/page.tsx file is misplaced; it should be inside products/details/page.tsx.

B. The details folder should be named [details] for dynamic routing.

C. The products folder must not have its own page.tsx when nested routes exist.

D. Missing page.tsx inside details folder.

Solution

1. Step 1: Verify folder and file placement

   The details/page.tsx must be inside products/details/ folder to match the route /products/details.

2. Step 2: Check the given structure

   The structure shows details/page.tsx inside app/ root, not nested under products/.

3. Final Answer:

   The details/page.tsx file is misplaced; it should be inside products/details/page.tsx. -> Option A

4. Quick Check:

   Nested route files must be inside matching nested folders [OK]

Hint: Check file location matches nested folder path exactly [OK]

Common Mistakes:

• Misplacing nested page.tsx outside correct folder
• Confusing dynamic and static folder names
• Removing parent page.tsx unnecessarily

5. You want to create a nested route /profile/settings/privacy in Next.js App Router. You also want to share a layout between /profile/settings and /profile/settings/privacy. How should you organize your folders and files inside app/?

hard

A. app/profile/settings/privacy/page.tsx only; layouts are not needed for nested routes

B. app/profile/settings/layout.tsx, app/profile/settings/page.tsx, app/profile/settings/privacy/page.tsx

C. app/profile/layout.tsx, app/profile/settings/page.tsx, app/profile/settings/privacy/page.tsx

D. app/profile/settings/page.tsx, app/profile/settings/privacy/layout.tsx, app/profile/settings/privacy/page.tsx

Solution

1. Step 1: Understand layout sharing in nested routes

   Layouts placed in a folder apply to all nested routes inside that folder.

2. Step 2: Organize folders for shared layout

   To share layout between /profile/settings and /profile/settings/privacy, place layout.tsx inside settings/ folder.

3. Step 3: Place page.tsx files correctly

   Put page.tsx inside settings/ and inside settings/privacy/ for those pages.

4. Final Answer:

   app/profile/settings/layout.tsx, app/profile/settings/page.tsx, app/profile/settings/privacy/page.tsx -> Option B

5. Quick Check:

   Layout in parent folder shares UI with nested pages [OK]

Hint: Put layout.tsx in parent folder to share with nested routes [OK]

Common Mistakes:

• Placing layout.tsx too deep to share with sibling routes
• Omitting layout.tsx and expecting shared UI
• Misplacing page.tsx files outside correct folders