Table of Contents
What is SSL Wildcard?
A Wildcard SSL Certificate is a special type of SSL that uses the * (asterisk) character in place of a subdomain name, allowing a single certificate to secure all subdomains at the same level of a domain — with no limit on quantity.
For example, a Wildcard Certificate for *.example.com covers:
- www.example.com
- shop.example.com
- blog.example.com
- mail.example.com
- api.example.com
- Any other first-level subdomain, unlimited
💡 Key Point: SSL Wildcard covers only one level deep. *.example.com covers shop.example.com but does not cover checkout.shop.example.com (two levels deep).
Wildcard vs Regular SSL — What's the Difference?
Before deciding, compare the main SSL types:
| Feature | Single Domain SSL | Wildcard SSL | Multi-Domain (SAN) SSL |
|---|---|---|---|
| Domains covered | 1 domain or subdomain | Unlimited subdomains (same level) | Multiple distinct domains (pre-listed) |
| Format | www.example.com | *.example.com | site1.com, site2.com, app.site3.net |
| Multi-level subdomains | ✗ | ✗ (one level only) | ✓ (explicit names) |
| Best for | Single website | Sites with multiple subdomains | Multiple unrelated domains |
| Relative cost | Cheapest | Cost-effective from 3+ subdomains | Depends on SAN count |
| EV support | ✓ | ✗ | ✓ |
When to Use SSL Wildcard
SSL Wildcard is the right choice in these situations:
1. You Have Multiple Subdomains on One Domain
If your site has 3 or more subdomains (e.g., www, shop, blog, api, admin), a single Wildcard Certificate is more economical than buying separate SSL for each subdomain.
2. You Plan to Add Subdomains in the Future
If your business is growing and you plan to launch new subdomains regularly, Wildcard covers them immediately — no new SSL purchase needed. This reduces management overhead significantly.
3. You Want to Simplify Certificate Management
Managing multiple SSL certificates separately (different renewal dates, separate installations) is tedious. Wildcard reduces it to one certificate — renew once, and every subdomain is protected.
4. Staging / Development Environments
Developers often use dev.example.com, staging.example.com, and test.example.com. Wildcard covers all of them without requesting separate SSL for each environment.
⚠️ Wildcard SSL is NOT recommended when: You only have 1–2 domains and no plans to add subdomains. Single Domain SSL is cheaper and sufficient for that use case.
Types of SSL Wildcard (DV / OV)
1. DV Wildcard (Domain Validation)
Verifies only that you own the domain. Issued within minutes to a few hours. Suitable for general websites, blogs, and applications that don't need to display an organization name in the certificate. Lower cost than OV.
2. OV Wildcard (Organization Validation)
Verifies both the domain and the organization. Requires business registration documents. Takes 1–3 business days. Ideal for corporate websites, e-commerce, and B2B businesses that need to demonstrate higher trust.
⚠️ Note: The CA/Browser Forum prohibits EV (Extended Validation) Wildcard certificates. If you need EV, use a Multi-Domain SAN certificate with explicitly named subdomains instead.
Pros and Cons of SSL Wildcard
Pros
- Cost-effective — One certificate covers unlimited subdomains
- Easy to manage — Renew once, maintain less
- Flexible — New subdomains are covered immediately, no new SSL needed
- Simple to install on DirectAdmin — Upload once, applies to all subdomains on the same server
- Great for SaaS / multi-tenant — Systems that auto-create subdomains per customer
Cons
- Shared private key — If the key is compromised, all subdomains are affected simultaneously
- One level only — Does not cover multi-level subdomains like a.b.example.com
- No EV support — Organizations needing EV must use SAN certificates
- Costlier than Single Domain — Not worth it for 1–2 subdomains only
- Wider attack surface — Some security scanners flag this as higher risk
Installing SSL Wildcard on DirectAdmin
AsiaGB Hosting uses DirectAdmin, making Wildcard SSL management straightforward through the control panel:
Installation Steps
- Log in to DirectAdmin and navigate to SSL Certificates
- Select "Paste a pre-generated certificate and key"
- Paste your Private Key into the "Private Key" field
- Paste your Certificate (CRT) into the "Certificate" field
- Paste your CA Bundle into the "Certificate Authority Bundle" field (important — don't skip)
- Click "Save"
- Verify that HTTPS is working on your target subdomains
💡 Tip: For subdomains sharing the same IP address, no additional configuration is needed — the system will automatically use the installed Wildcard Certificate. If a subdomain is on a different server, install the certificate there separately.
Renewing SSL Wildcard
When the certificate approaches expiry (SSL certificates are typically valid for 1 year), the renewal process is:
- Purchase a new SSL Wildcard from AsiaGB
- Submit a new CSR generated from DirectAdmin
- Verify domain ownership
- Receive the new certificate and install it to replace the old one
Pricing at AsiaGB
| Product | RapidSSL Wildcard | GeoTrust QuickSSL Premium Wildcard |
|---|---|---|
| Price/year | THB 5,000 | THB 7,000 |
| Type | DV Wildcard | DV Wildcard |
| Issuance time | Minutes to a few hours | Minutes to a few hours |
| Subdomains covered | Unlimited | Unlimited |
| Best for | Startups, general websites | Enterprise, premium brand trust |
For OV Wildcard with organization identity verification, please contact the AsiaGB team for pricing and details.
Frequently Asked Questions (FAQ)
*.example.com covers shop.example.com and blog.example.com, but not checkout.shop.example.com. For two-level subdomains, use a nested Wildcard or Multi-Domain SAN certificate.www.example.com). Wildcard SSL uses *.example.com to cover all subdomains at the same level with no quantity limit.Summary: When Should You Choose SSL Wildcard?
SSL Wildcard is the most cost-effective and convenient choice for websites with 3 or more subdomains, or those planning to expand their subdomain structure. Managing one certificate is far simpler than juggling multiple separate SSL certificates.
However, if you only have 1–2 domains with no expansion plans, or if you need EV certificates for maximum trust, single-domain or Multi-Domain SAN SSL may be a better fit.
AsiaGB offers RapidSSL Wildcard at THB 5,000/year, with a support team available to assist with installation and configuration on DirectAdmin around the clock.
Ready to Secure All Your Subdomains?
AsiaGB offers RapidSSL Wildcard at THB 5,000/year — covering all subdomains under one domain, with expert installation support on DirectAdmin.
Order SSL Wildcard