Custom domains in Supabase - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a custom domain in the context of Supabase?

A custom domain is a personalized web address you own and connect to your Supabase project instead of using the default Supabase URL.

beginner

Why use a custom domain for your Supabase project?

Using a custom domain makes your project look professional, easier to remember, and helps with branding and trust for your users.

intermediate

What DNS record type is commonly used to point a custom domain to a Supabase project?

A CNAME record is usually used to point your custom domain to the Supabase project's URL.

intermediate

What is the role of SSL certificates when setting up a custom domain in Supabase?

SSL certificates secure the connection between users and your custom domain by encrypting data, ensuring privacy and trust.

intermediate

What is a common step after adding a custom domain in Supabase to make it active?

You need to verify domain ownership and configure DNS records correctly, then wait for DNS propagation before the custom domain works.

What type of DNS record do you usually create to connect a custom domain to Supabase?

A CNAME

B MX

C TXT

D NS

CNAME records point your custom domain to the Supabase URL, linking them together.

Why is SSL important for custom domains in Supabase?

A It encrypts data to keep connections secure

B It speeds up the website loading time

C It changes the domain name

D It stores user data

SSL encrypts data between users and your site, protecting privacy and building trust.

What must you do after adding a custom domain in Supabase before it works?

A Delete the default Supabase URL

B Restart your computer

C Verify domain ownership and update DNS records

D Change your Supabase password

You need to prove you own the domain and set DNS records so traffic goes to your Supabase project.

Which of these is NOT a benefit of using a custom domain?

A Better branding

B Automatic data backup

C Easier to remember URL

D More professional appearance

Custom domains improve branding and appearance but do not handle data backup.

How long can DNS propagation take after setting a custom domain?

A It is instant

B A few seconds

C One minute

D Several hours to a day

DNS changes can take hours or up to a day to spread worldwide.

Explain the steps to set up a custom domain for a Supabase project.

Think about what you do with your domain provider and Supabase dashboard.

Why is it important to use SSL certificates with custom domains in Supabase?

Consider what happens when you see a padlock icon in your browser.

Practice

1. What is the main purpose of setting a custom domain in Supabase?

easy

A. To enable faster query execution

B. To increase database storage capacity

C. To create multiple user accounts automatically

D. To use your own website address instead of a default Supabase URL

Solution

1. Step 1: Understand what a custom domain is

   A custom domain lets you use your own website address instead of a generic one provided by a service.

2. Step 2: Relate to Supabase usage

   In Supabase, setting a custom domain means your app uses your own URL, making it look professional and branded.

3. Final Answer:

   To use your own website address instead of a default Supabase URL -> Option D

4. Quick Check:

   Custom domain = Own website address [OK]

Hint: Custom domain means your own website address [OK]

Common Mistakes:

• Thinking it increases database size
• Confusing with performance features
• Assuming it creates user accounts

2. Which DNS record type must you add to point your custom domain to Supabase?

easy

A. CNAME record

B. MX record

C. TXT record

D. SRV record

Solution

1. Step 1: Identify DNS record types for domain pointing

   CNAME records are used to alias one domain name to another, commonly used to point custom domains to services.

2. Step 2: Match with Supabase custom domain setup

   Supabase requires a CNAME record to link your custom domain to their servers.

3. Final Answer:

   CNAME record -> Option A

4. Quick Check:

   Custom domain pointing uses CNAME [OK]

Hint: Use CNAME to point domain to Supabase [OK]

Common Mistakes:

• Using MX record which is for email
• Using TXT record meant for verification
• Confusing SRV record with domain pointing

3. Given this Supabase custom domain setup snippet:

domain: "app.example.com"
records: [
  { type: "CNAME", value: "db.supabase.co" }
]

What happens when a user visits app.example.com?

medium

A. They are redirected to the Supabase database interface

B. Their browser connects to Supabase hosting for the app

C. They get an email verification prompt

D. They see a DNS error because CNAME is incorrect

Solution

1. Step 1: Understand CNAME effect

   The CNAME record points the domain to Supabase's hosting address, so requests go there.

2. Step 2: Interpret user visit behavior

   When visiting app.example.com, the browser connects to Supabase hosting serving the app, not the database interface or errors.

3. Final Answer:

   Their browser connects to Supabase hosting for the app -> Option B

4. Quick Check:

   CNAME directs browser to Supabase hosting [OK]

Hint: CNAME points domain to hosting, not email or errors [OK]

Common Mistakes:

• Confusing database interface with hosting
• Assuming DNS error from correct CNAME
• Thinking email verification appears on visit

4. You set a custom domain in Supabase but get a security warning in browsers. What is the most likely cause?

medium

A. You did not add an MX record

B. You used an invalid domain name format

C. You forgot to enable SSL for the custom domain

D. You set the CNAME to the wrong IP address

Solution

1. Step 1: Identify cause of browser security warnings

   Security warnings usually happen when SSL (secure connection) is missing or invalid.

2. Step 2: Relate to Supabase custom domain setup

   Supabase requires enabling SSL for custom domains to avoid browser warnings.

3. Final Answer:

   You forgot to enable SSL for the custom domain -> Option C

4. Quick Check:

   Missing SSL causes browser security warnings [OK]

Hint: Always enable SSL for custom domains [OK]

Common Mistakes:

• Confusing MX record with SSL
• Thinking domain format causes security warning
• Assuming CNAME IP address is used instead of hostname

5. You want to set up a custom domain dashboard.myapp.com for your Supabase project. Which steps must you follow to ensure it works correctly and securely?

hard

A. Buy the domain, add a CNAME DNS record pointing to Supabase, then enable SSL in Supabase settings

B. Buy the domain, add an MX record pointing to Supabase, then enable SSL in Supabase settings

C. Buy the domain, add a TXT record for verification, then disable SSL to avoid errors

D. Buy the domain, add an A record pointing to Supabase IP, then skip SSL setup

Solution

1. Step 1: Purchase domain and configure DNS

   First, buy your domain (dashboard.myapp.com) and add a CNAME record pointing to Supabase's domain to route traffic correctly.

2. Step 2: Enable SSL for secure connections

   Then, enable SSL in Supabase settings to secure the connection and avoid browser warnings.

3. Final Answer:

   Buy the domain, add a CNAME DNS record pointing to Supabase, then enable SSL in Supabase settings -> Option A

4. Quick Check:

   Domain + CNAME + SSL = Correct setup [OK]

Hint: Domain + CNAME + SSL = working custom domain [OK]

Common Mistakes:

• Using MX or TXT records incorrectly
• Skipping SSL causing security warnings
• Using A record instead of CNAME for Supabase