Custom domains in Supabase - Step-by-Step Execution

Process Flow - Custom domains

User owns domain

↓

Add domain to Supabase project

↓

Supabase provides DNS records

↓

User updates DNS provider with records

↓

DNS propagates changes

↓

Supabase verifies domain

↓

Domain active

The user adds their domain to Supabase, updates DNS records as instructed, then Supabase verifies the domain to activate it.

Execution Sample

Supabase

1. Add domain example.com in Supabase
2. Supabase shows DNS records
3. Update DNS provider with records
4. Wait for DNS propagation
5. Supabase verifies domain
6. Domain becomes active

This sequence shows how a user sets up a custom domain in Supabase step-by-step.

Process Table

Step	Action	Input/Condition	Result	Next Step
1	User adds domain	Domain = example.com	Supabase accepts domain	Supabase shows DNS records
2	Supabase provides DNS records	Records for example.com	User sees records to add	User updates DNS provider
3	User updates DNS	Adds records to DNS provider	DNS records set	Wait for DNS propagation
4	Wait for DNS propagation	DNS changes propagate	Propagation in progress	Supabase verifies domain
5	Supabase verifies domain	Checks DNS records	Records correct?	Yes -> Domain active; No -> Wait or fix DNS
6	Domain status	Verified	Domain active and serving	End
7	Domain status	Not verified	Domain inactive	User fixes DNS and retries

💡 Domain becomes active when DNS records are verified by Supabase.

Status Tracker

Variable	Start	After Step 1	After Step 3	After Step 5	Final
domain	none	example.com	example.com	example.com	example.com
dns_records_set	false	false	true	true	true
dns_verified	false	false	false	true/false	true (active) or false (inactive)
domain_status	none	pending	pending	verified or not	active or inactive

Key Moments - 3 Insights

Why does the domain stay inactive after adding DNS records?

Because DNS propagation takes time; Supabase verification (step 5) only succeeds after propagation completes, as shown in execution_table row 4 and 5.

What happens if DNS records are incorrect?

Supabase verification fails (execution_table row 7), so the domain remains inactive until DNS records are fixed.

Why must the user update DNS records at their DNS provider?

Supabase cannot change DNS records itself; the user must add the provided records to their DNS provider for verification and activation (execution_table row 3).

Visual Quiz - 3 Questions

Look at the execution table, at which step does Supabase check if DNS records are correct?

A Step 5

B Step 4

C Step 2

D Step 3

💡 Hint

Check the 'Action' and 'Result' columns in execution_table row 5.

According to variable_tracker, what is the value of 'dns_records_set' after Step 3?

A false

B none

C true

D pending

💡 Hint

Look at the 'dns_records_set' row under 'After Step 3' in variable_tracker.

If DNS propagation is not complete, what will be the domain status according to execution_table?

A active

B pending

C inactive

D verified

💡 Hint

Refer to execution_table row 4 and the 'domain_status' variable in variable_tracker.

Concept Snapshot

Custom domains in Supabase:
1. Add your domain in Supabase project.
2. Supabase gives DNS records to add at your DNS provider.
3. Update DNS records and wait for propagation.
4. Supabase verifies DNS records.
5. Once verified, domain becomes active.

Full Transcript

To use a custom domain with Supabase, you first add your domain name in the Supabase project settings. Supabase then provides specific DNS records that you must add at your domain's DNS provider. After updating these DNS records, you wait for the changes to propagate across the internet. Supabase periodically checks these DNS records to verify ownership and correctness. When verification succeeds, your custom domain becomes active and serves your Supabase project. If verification fails, you need to check and fix your DNS records. This process ensures your domain is properly linked and secure.

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