Domains
Coolify uses domains to route public HTTP and HTTPS traffic through the proxy to an application or a web-facing service container.
The domain's DNS record points to the server running the resource. The Coolify proxy then matches the hostname and path and forwards the request to the correct container port.
Choose a domain option
Choose the option that matches how you plan to use the resource.
A domain does not expose a standalone database. Use the database's public port when an external client must connect.
These instructions assume the server uses the integrated Traefik or Caddy proxy. With Custom (None), you must configure routing and TLS in your own proxy. See Proxy overview before continuing.
Add a custom domain
Before starting, point the domain to the resource server and verify its DNS records. Inbound TCP ports 80 and 443 must be open on the resource server, and the application must listen on the container port that Coolify will target.
Enter the domain in Coolify
Open the application or the web-facing application inside a service, then open its General configuration.
Enter the complete URL in Domains, including http:// or https://. For example, enter https://app.shadowarcanist.com.
For a Docker Compose application, Coolify shows a separate Domains for <service-name> field for each non-database service. Add the domain to the service that receives the request.
Select Save.
Redeploy and verify the domain
Redeploy the resource so the proxy uses the new configuration.
After the deployment completes:
- Confirm the hostname resolves to the expected server or CDN.
- Open the configured URL in a browser.
- Confirm it loads the intended application.
- For an
https://URL, confirm the browser shows the expected certificate.
If DNS was changed recently, you may need to wait for the previous record's TTL to expire.
Supported domain formats
The Domains field accepts one or more complete URLs.
| Goal | Value in Domains |
|---|---|
| Route one hostname | https://app.example.com |
| Route multiple hostnames | https://app.example.com,https://www.example.com |
Target container port 3000 | https://app.example.com:3000 |
Route a path to container port 80 | https://app.example.com/api |
Route a path to container port 8080 | https://app.example.com:8080/api |
When a domain value does not include a port, Coolify routes traffic to port 80 inside the container. Add the container port to the URL when the application listens on a different port.
Separate multiple URLs with commas. Coolify converts application domains to lowercase and removes duplicate entries when you save them.
When a value contains both a port and a path, put the port before the path:
- Correct:
https://app.shadowarcanist.com:8080/api - Incorrect:
https://app.shadowarcanist.com/api:8080
Route to a port or path
The port in a domain value selects the port inside the container. It does not create a public host-port mapping. Visitors still reach an https:// domain through the proxy on port 443.
| Domain value | Proxy behavior |
|---|---|
https://app.shadowarcanist.com | Send requests for the hostname to port 80 inside the container. |
https://app.shadowarcanist.com:3000 | Send requests for the hostname to port 3000 inside the container. |
https://shadowarcanist.com/api | Send requests beginning with /api to port 80 inside the container. |
https://shadowarcanist.com:8080/api | Send requests beginning with /api to port 8080 inside the container. |
Path-based routes let several resources share one hostname. For example, one application can use https://shadowarcanist.com, while another uses https://shadowarcanist.com/api.
Coolify creates a path-prefix route from the value. More specific paths take priority over the root route in the proxy's routing model.
Control prefix stripping
By default, Coolify strips the configured prefix before forwarding the request. A request to https://shadowarcanist.com/api/users reaches the application as /users.
Disable Strip Prefixes in the resource's advanced settings when the application expects to receive /api/users instead.
Keep every resource serving a shared hostname running and healthy. If a path route is unavailable, the result depends on the remaining proxy routes and application responses.
Configure HTTPS and redirects
Use an https:// URL when you want the integrated proxy to configure TLS. Coolify generates the route, and Traefik or Caddy requests and renews the certificate.
An http:// value creates an HTTP route. Other resource or proxy settings can still redirect that route to HTTPS.
The hostname must resolve through the resource server or a correctly configured CDN, ports 80 and 443 must reach the Coolify proxy, and the domain must be present in the resource configuration.
If the browser shows a certificate warning, follow Let's Encrypt not working. For wildcard certificates, follow the guide for Traefik or the Caddy DNS challenge.
Redirect www and non-www
For a non-Docker Compose application, add both hostnames to Domains and create DNS records for both. Then use Direction to choose the canonical hostname.
| Direction | Behavior |
|---|---|
| Allow www & non-www | Serve both configured hostnames without a Coolify-managed redirect. |
| Redirect to www | Redirect the non-www hostname to the configured www hostname. |
| Redirect to non-www | Redirect the www hostname to the configured non-www hostname. |
Coolify will not enable Redirect to www unless a www URL is present in Domains. The corresponding www DNS record must also resolve to the resource server.
Use generated domains
Coolify can generate an application domain from the server's Wildcard Domain setting.
Before configuring generated domains, create and verify a wildcard DNS record for the server.
Configure the server wildcard domain
In Coolify, open Servers, select the server, and open General. Enter https://shadowarcanist.com in Wildcard Domain, then save the server.
Generate an application domain
Open an application on that server and select Generate Domain beside Domains.
Coolify generates a hostname such as https://<application-id>.shadowarcanist.com. Open the generated URL after redeploying the application to confirm it works.
The wildcard setting affects generated domains; it does not change domains already assigned to resources.
When Wildcard Domain is empty, Coolify can generate an sslip.io domain from the server IP address. Use that URL to verify a deployment or proxy route before configuring your own domain.
Resolve domain conflicts
Coolify warns when the same complete domain is already assigned to another application, service, or the Coolify dashboard in the same team.
Reusing a domain can make routing unpredictable and can prevent the correct TLS certificate from being served. Only one resource can receive the traffic reliably.
Open the resource linked in the conflict message and remove or change its domain. Override the warning only when you are deliberately replacing that route.
Set the Coolify dashboard domain
Self-hosted users can assign a domain to the Coolify dashboard from Settings > Configuration > General.
Set URL to a complete value such as https://coolify.shadowarcanist.com only after you point its DNS record to the server running Coolify. Do not reuse an application or service domain for the dashboard.
Read Instance settings for the complete setting reference.
Continue with domain routing
Use these guides to prepare the public route or investigate a domain that does not work as expected.
Configure the firewall
Open the ports required for HTTP, HTTPS, and certificate issuance on the resource server.
Troubleshoot certificates
Check DNS, proxy reachability, rate limits, and certificate resolver errors.
Troubleshoot proxy routing
Trace a failed route from the proxy to the application container and its target port.