Every website should have an SSL Certificate to encrypt data and display the padlock icon in browsers. But between free SSL like Let's Encrypt and paid SSL such as DV/OV/EV — what exactly is the difference, and which is right for your business? This article answers every question.
What Is an SSL Certificate — A Quick Review
SSL (Secure Sockets Layer), now technically TLS (Transport Layer Security), is a protocol that encrypts data transmitted between a user's browser and your web server, making it unreadable if intercepted. Websites with SSL installed display https:// and a padlock icon in the address bar.
Google also uses HTTPS as a ranking factor in search, so having SSL benefits both security and SEO performance.
Free SSL (Let's Encrypt) — What Is It?
Let's Encrypt is a non-profit Certificate Authority (CA) backed by Mozilla, EFF, and other partners. It issues Domain Validation (DV) SSL Certificates completely free to anyone. The Validity Period is only 90 days, requiring more frequent renewals — typically automated via Certbot or through your hosting Control Panel.
Key fact: Let's Encrypt provides encryption that is just as strong as paid SSL from a data security standpoint. The differences lie in identity validation, warranty coverage, and the trust signals shown to your customers.
Types of Paid SSL Certificates
DV SSL (Domain Validation)
Verifies domain ownership only. Issues within minutes. Suitable for general websites, blogs, and landing pages that need HTTPS without organizational identity verification.
OV SSL (Organization Validation)
Verifies both domain and organization details. Takes 1-3 business days. The company name appears in Certificate Details. Recommended for businesses that want to demonstrate credibility.
EV SSL (Extended Validation)
Most rigorous vetting process. Takes 3-7 business days. Originally browsers displayed the company name in green. Best for banks, financial institutions, and large e-commerce sites.
Free SSL vs Paid SSL Comparison Table
| Feature | Free SSL (Let's Encrypt) | Paid SSL (DV/OV/EV) |
|---|---|---|
| Price | Free — no cost | DV from ฿1,000/year; OV/EV higher |
| Validation Level | Domain Validation only | DV / OV / EV depending on tier purchased |
| Validity Period | 90 days (frequent renewal required) | 1–2 years (more convenient) |
| Auto-Renew | Possible but requires setup | Manual renewal but infrequent |
| Warranty | No warranty | DV: $10,000–$100,000 / OV: higher / EV: highest |
| Wildcard (*.domain.com) | Supported (Let's Encrypt Wildcard) | Supported (higher price than single domain) |
| Browser Display | Standard padlock — no company name shown | OV/EV: company name visible in Certificate Details |
| Trust Level | Secure but no organizational identity | OV/EV clearly verifies organizational identity |
| E-Commerce Suitability | Small shops — acceptable | Larger stores — OV/EV recommended for customer trust |
| Brand / CA | Let's Encrypt | RapidSSL, GeoTrust, DigiCert (available from AsiaGB) |
| Multi-domain (SAN) | Supports multiple domains in one cert | Supported (Multi-domain / SAN SSL) |
| Support | Community forums | Support from CA and reseller |
| On AsiaGB Hosting | Free — easy install via DirectAdmin | From ฿1,000/year — order at asiagb.com/ssl |
How the Issuance Process Differs by Certificate Type
Beyond validation levels, the process of obtaining an SSL certificate varies significantly between types — affecting both how long you wait and what steps you need to take.
Let's Encrypt — Fully Automated
Let's Encrypt uses the ACME (Automatic Certificate Management Environment) protocol to issue certificates automatically. Tools like Certbot communicate with the CA to prove you control the domain via one of these methods:
- HTTP-01 Challenge: Certbot creates a temporary file in your web root; Let's Encrypt fetches it to verify.
- DNS-01 Challenge: Add a TXT record to your DNS to prove ownership — required for Wildcard certificates.
- TLS-ALPN-01 Challenge: Verification via a TLS handshake on port 443.
The entire process takes just seconds. If your control panel supports it — like AsiaGB's DirectAdmin — auto-renew is configured automatically with no manual action required.
Paid DV SSL — Fast But Manual
DV SSL from CAs like RapidSSL or GeoTrust uses Domain Control Validation (DCV) similar to Let's Encrypt, but requires processing through a reseller's system or directly with the CA. Certificates typically issue within 5–15 minutes after DCV is confirmed.
OV/EV SSL — Organization Verification Required
OV and EV certificates require additional documents and verification from the CA — such as articles of incorporation, business registration documents, or a phone confirmation call. This takes 1–7 business days depending on the level. The result: your organization name appears in Certificate Details, building substantial trust with customers.
| Type | Issuance Time | Documents Required | Validity |
|---|---|---|---|
| Let's Encrypt DV | Seconds (automated) | None | 90 days |
| Paid DV SSL | 5–15 minutes | None (DCV only) | 1–2 years |
| OV SSL | 1–3 business days | Company documents | 1–2 years |
| EV SSL | 3–7 business days | Company docs + additional verification | 1 year |
SSL and SEO — Does It Really Affect Google Rankings?
Google officially confirmed as early as 2014 that HTTPS is a ranking signal. While it's described as a "lightweight" signal, it does have a real effect — especially compared to sites still running on plain HTTP. Today, Chrome shows a prominent "Not Secure" warning on HTTP pages, which directly increases bounce rates and erodes visitor trust.
More critically, since 2021 Googlebot crawls the web primarily over HTTPS. If your site is still HTTP-only, Google may crawl and index it more slowly or incompletely. Core Web Vitals and security-related signals also have indirect effects on rankings.
Common SSL and SEO Misconceptions
- Free and paid SSL have the same SEO impact — Google does not differentiate between certificate authorities. All that matters is a valid, non-expired HTTPS connection.
- An expired certificate immediately harms rankings — When SSL expires, browsers display an error page. Googlebot sees the same error, which can cause rankings to drop.
- Mixed content reduces SEO — If your page loads images or scripts over HTTP while using HTTPS, browsers will flag or block mixed content, undermining the security signal.
- HTTP → HTTPS redirects must be done correctly — Use a 301 (permanent) redirect to signal to Google that the change is permanent, not a 302 (temporary).
Wildcard SSL and SAN SSL — When to Use Each
For websites with multiple subdomains or multiple domains within the same organization, two SSL types can significantly reduce both cost and management complexity.
Wildcard SSL (*.domain.com)
Wildcard SSL covers all subdomains at a single level. For example, *.asiagb.com covers shop.asiagb.com, blog.asiagb.com, api.asiagb.com, and all other subdomains — but does not cover sub.shop.asiagb.com (two levels deep).
- Let's Encrypt issues Wildcard certificates free via DNS-01 Challenge
- AsiaGB offers RapidSSL Wildcard at ฿5,000/year with warranty and support
- Best for sites with multiple subdomains such as
www / api / shop / admin
SAN SSL (Multi-Domain)
SAN (Subject Alternative Name) SSL covers multiple different domains in a single certificate — for example, asiagb.com, billing.in.th, and dnsxray.com all in one certificate. This reduces cost and simplifies management compared to buying separate certificates for each domain. Ideal for organizations managing multiple domains on a shared infrastructure.
# Check SAN entries in a certificate using openssl
openssl s_client -connect asiagb.com:443 -servername asiagb.com 2>/dev/null \
| openssl x509 -noout -text \
| grep -A1 "Subject Alternative Name"Is the Encryption Actually Different?
In terms of encryption strength, no — there is no difference. Both free and paid SSL certificates use TLS 1.2/1.3 with 2048-bit RSA or 256-bit ECC keys. Data transmitted between your users and your server is encrypted equally strongly.
What differs is identity validation. Free SSL only verifies you own the domain. It doesn't verify who or what organization is behind the website. OV and EV certificates go through a much more rigorous vetting process to confirm your organizational identity.
What Does the Warranty on Paid SSL Actually Mean?
Paid SSL certificates from leading CAs include a warranty covering damages arising from a mis-issued or compromised certificate — providing a guarantee to your customers. Examples include:
- RapidSSL DV: $10,000 warranty
- GeoTrust DV: $100,000 warranty
- DigiCert EV: Highest warranty in the market
Let's Encrypt offers no warranty of any kind, as it is a free, non-profit service.
Summary: Which SSL Is Right for You?
- Blog / Portfolio / Landing Page: Free SSL (Let's Encrypt) is sufficient — free and secure.
- Business website / General SME: Paid DV SSL (from ฿1,000/year) adds trust, warranty, and peace of mind.
- Mid-size online store: OV SSL recommended — company name in Certificate builds customer trust.
- Banks / Financial institutions / Large e-commerce: EV SSL is essential for maximum trust signals.
- Sites with many subdomains: Wildcard SSL — either free or paid (AsiaGB offers Wildcard DV).
Warning: Let's Encrypt certificates expire every 90 days. If you don't set up auto-renew and forget, your certificate will expire and browsers will show a "Not Secure" warning — immediately harming both SEO and visitor confidence. Paid SSL with 1–2 year validity is significantly easier to manage.
SSL Certificates for Every Need
RapidSSL, GeoTrust, DigiCert — DV/Wildcard/OV/EV from ฿1,000/year with warranty and Thai-language support
View All SSL Certificates