How to Attach a Custom Domain to AWS Services (Step-by-Step Beginner Guide)

Attaching a custom domain (like codearchitecture.in) to AWS services is one of the most important steps when deploying real-world applications.

By default, AWS gives you long, ugly URLs like:

But in production, you want something clean, professional, and brand-friendly:

In this complete guide, you’ll learn:

• What a custom domain really means in AWS

• How DNS, SSL, and AWS services work together

• How to attach custom domains to S3, CloudFront, API Gateway, Amplify, and ALB

• Common mistakes (and how to avoid them)

This tutorial is beginner-safe, even if you’re touching AWS for the first time.

What Is a Custom Domain in AWS?

A custom domain is simply your own domain name (purchased from a domain registrar) mapped to an AWS service.

Instead of users accessing your app via an AWS-generated URL, DNS routes traffic from your domain to the AWS resource.

Example:

AWS Services That Support Custom Domains

You can attach custom domains to almost all major AWS services:

• Amazon S3

• Amazon CloudFront

• Amazon API Gateway

• AWS Amplify

• Elastic Load Balancer

• Amazon Route 53

High-Level Architecture (How Everything Connects)

Flow looks like this:

Step 1: Buy a Domain Name

You can buy a domain from:

• Amazon Route 53

• GoDaddy

• Namecheap

• Hostinger

Step 2: Understand DNS Records (Very Important)

Before touching AWS, understand these records:

Example:

Step 3: Create an SSL Certificate (Mandatory)

AWS requires HTTPS for custom domains.

Use AWS Certificate Manager (ACM)

Steps:

1. Go to AWS Certificate Manager

2. Click Request a certificate

3. Enter:

4. Choose DNS validation

5. Add the provided CNAME record in your DNS provider

⚠️ Region Rule (Very Important):

Step 4: Attach Custom Domain to CloudFront (S3 / Next.js / Static Sites)

Steps:

1. Open CloudFront

2. Select your distribution

3. Go to Settings → Edit

4. Add:

5. Select SSL certificate from ACM

6. Save & deploy

DNS Record:

Step 5: Attach Custom Domain to API Gateway

Steps:

1. Open API Gateway

2. Go to Custom domain names

3. Create new domain:

4. Select ACM certificate

5. Choose endpoint type:

6. Map API & stage

DNS Record:

Step 6: Attach Custom Domain to AWS Amplify (React / Next.js)

Amplify is the easiest.

Steps:

1. Open AWS Amplify

2. Select your app

3. Go to Domain management

4. Add domain

5. Amplify will show DNS records

6. Add them to your DNS provider

✅ Amplify automatically:

• Creates SSL certificate

• Handles renewals

• Manages redirects

Step 7: Attach Custom Domain to Application Load Balancer (ALB)

Steps:

1. Create HTTPS Listener (443)

2. Attach ACM certificate

3. Point listener to target group

DNS Record:

Common Mistakes (Avoid These!)

• Certificate in wrong region

• Forgetting DNS validation

• Using CNAME on root domain instead of ALIAS

• Expecting instant propagation (DNS takes time)

• Mixing CloudFront + API Gateway certificates

How Long Does It Take to Work?

SEO & Production Best Practices

• Always redirect HTTP → HTTPS

• Use www → non-www (one canonical)

• Use CloudFront for caching

• Enable gzip / brotli

• Set proper cache headers

Final Thoughts

Attaching a custom domain in AWS may look scary at first, but once you understand:

• DNS

• SSL

• Service-specific rules

…it becomes a repeatable 10-minute process.

This setup is mandatory for production-grade applications and a huge plus in interviews and freelancing projects.