Protect Your Site with HTTPS and Strengthen SEO: Essential Knowledge for Site Owners

HTTPS is indispensable if you want to exchange information safely on the internet. The padlock shown in the browser address bar is proof that a site uses HTTPS. In reality, HTTPS does not only improve site security. It also has a major effect on SEO.

This article explains the mechanism and benefits of HTTPS, how to migrate from HTTP to HTTPS, and the concrete settings that help improve SEO, in a way that both beginners and site operators can understand.

If you want to achieve both safe website operation and solid SEO, now is the time to adopt HTTPS.

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What is HTTPS? A beginner-friendly explanation

When you browse a website on the internet, you have probably seen either “http://” or “https://” in the address bar. Whether that final “s” is present makes a major difference to the safety of the website.

This chapter explains what HTTPS is and why it matters in a way that is easy for beginners to follow.

The difference between HTTP and HTTPS and the secret of the padlock

The biggest difference between HTTP and HTTPS is whether communication is encrypted. HTTP stands for HyperText Transfer Protocol and is the protocol used to exchange information between a website and a browser. But with HTTP, the contents of that communication are not encrypted, which means they may be intercepted or tampered with by third parties.

HTTPS stands for HyperText Transfer Protocol Secure and protects communication using encryption technology called SSL/TLS. The padlock that appears in the address bar is the sign that the connection is using HTTPS. By clicking that padlock, users can verify the security-certificate information for the site.

★ What are SSL and TLS? How encryption protects information and why it matters

How HTTPS protects communication through encryption

HTTPS is the mechanism that allows data to move safely between a website and your browser. A simple analogy is putting a letter inside an envelope before sending it. With HTTP, the contents of the letter can be read by anyone along the way.

With HTTPS, by contrast, the contents are encrypted so that only the intended recipient can read them. That helps prevent personal information, passwords, and other important data from being stolen.

This encryption relies on digital certificates called SSL/TLS certificates. These certificates prove the identity of a website and provide the keys needed for encrypted communication.

Why HTTPS matters: better security and stronger trust

Many threats exist on the internet. Malicious third parties may intercept HTTP communication to steal personal information or tamper with a website to show false content. HTTPS is indispensable for protecting websites and users from these threats and for providing a safe browsing experience.

This is especially true for e-commerce sites, online banking, and any other website that handles personal information or payment details. In those cases, using HTTPS is essentially mandatory. Entering personal information on a website that does not use HTTPS is highly risky.

Three benefits of HTTPS: SEO, security, and trust

Migrating a website to HTTPS creates three major benefits.

• Better SEO performance: Google treats HTTPS as one of its ranking signals, so an HTTPS site may have an advantage in search rankings.
• Stronger security: Encryption reduces the risk that important data such as personal information and payment details will be intercepted or altered.
• Greater trust: The padlock in the address bar communicates safety visually and can increase user confidence, which may also improve conversions.

Google has explicitly stated that HTTPS is used as a ranking signal.

Over the past few months, Google has been running tests that take into account whether sites use secure, encrypted connections as a signal in ranking algorithms. Since the results were positive, Google decided to use HTTPS as a ranking signal.

HTTPS as a ranking signal

Understand how HTTPS works

Understanding how HTTPS protects a website is important for safe site operation. This chapter explains the roles of SSL/TLS certificates, encrypted communication, and trailing slashes in URLs.

SSL/TLS certificates: the identity document of a website

An SSL/TLS certificate is a digital certificate that proves the identity of a website. Much like a driver’s license or passport, it contains information that verifies the website itself. Browsers examine the certificate to confirm that the site they are connecting to is genuine, and that makes secure communication possible.

There are several kinds of certificates, including domain-validated certificates, organization-validated certificates, and EV SSL certificates. Their validation levels and prices differ, so it is important to choose the right one for the nature of the site.

How encrypted communication protects against interception and tampering

HTTPS uses SSL/TLS certificates to encrypt communication. In practical terms, communication is protected through the following process.

1. When a browser accesses a website over HTTPS, the website sends an SSL/TLS certificate.
2. The browser checks that the certificate is valid and, if there is no problem, generates encryption keys.
3. Those keys are used to encrypt the data exchanged between the browser and the website.
4. Even if third parties intercept the encrypted data, they cannot read it.

Because of this mechanism, eavesdropping and tampering can be prevented and data can be exchanged safely.

Why the trailing slash matters in HTTPS URLs

Whether a URL ends with a trailing slash also matters from an SEO perspective. Search engines may recognize “https://example.com” and “https://example.com/” as separate pages. That can create duplicate-content issues and may harm SEO.

For Google, it is not a problem if the slashed and non-slashed versions of a URL contain different content, but in most cases this is not ideal for users.

To slash or not to slash

As a rule of thumb, it is recommended to standardize homepage URLs with a trailing slash. What matters is to avoid confusion by following a consistent rule across the entire website.

Use HTTPS to strengthen SEO and search performance

SEO is extremely important for any website operator. If you rank highly in search, more users can find the site and traffic increases. This chapter explains in detail how migrating to HTTPS affects SEO.

Google recommends HTTPS because it supports SEO

Google actively promotes HTTPS because it wants to provide a safe internet experience for users. In 2014, Google officially announced that HTTPS would be used as one of its ranking signals. In other words, websites that use HTTPS receive a small ranking advantage.

That shows Google sees HTTPS as a sign of trust and safety. For that reason, HTTPS should be treated as an essential part of SEO.

Positive SEO effects created by migrating to HTTPS

Migrating to HTTPS does not instantly create dramatic ranking improvements on its own, but it can have several positive effects.

• Ranking improvements: Because HTTPS is a ranking signal, an HTTPS site may rank above an otherwise similar HTTP site.
• Better crawl priority: Google tends to prioritize crawling HTTPS sites, which can help more pages get indexed and shown in search.
• Better user experience: Since HTTPS improves site security, users can browse more confidently. That can reduce bounce rate and increase time on site, which is good for SEO indirectly.
• Protection of referrer information: Referrer information sent from HTTPS sites is protected, which supports more accurate analytics.

A stronger presence in search results through user trust

Moving to HTTPS also affects how users perceive your site in search results. Browsers such as Google Chrome now show warnings such as “Not secure” for websites that do not use HTTPS. Those warnings can make users uneasy and cause them to leave.

By contrast, sites that use HTTPS show a padlock in the address bar and give users a sense of safety. That raises the perceived trustworthiness of the site and can improve click-through rates.

How to migrate to HTTPS now: a step-by-step guide

At first glance, moving a site to HTTPS may seem complicated, but in reality the process is not as difficult as it appears. This chapter explains the steps in order so that even beginners can proceed smoothly.

How to make a homepage use HTTPS in practical terms

The basic steps for enabling HTTPS are as follows.

1. Obtain an SSL/TLS certificate: Acquire an appropriate certificate from a certificate authority. Check which certificate type is needed for your server environment.
2. Install the certificate on the server: Install the certificate you obtained on the web server.
3. Change the website settings: Edit the site configuration so that the website can be accessed over HTTPS.
4. Set up redirects: Automatically send users who access the site via HTTP to the HTTPS version.
5. Verify the result: Confirm that the site is accessible over HTTPS and that every part of the content loads correctly.

How HTTPS settings differ across server types

The setup procedure for HTTPS depends on the type of server you use. Here are examples for several common server environments.

• Apache: Add settings to the .htaccess file or the virtual-host configuration.
• Nginx: Add SSL/TLS settings to the server configuration file.
• IIS: Add the server certificate and configure bindings.

For the exact steps, review the official documentation for the server software you use.

How to obtain and install SSL/TLS certificates

SSL/TLS certificates are issued by certificate authorities, or CAs. You can choose from several types, including free certificates such as Let’s Encrypt and paid commercial certificates. The right choice depends on the scale of the website and its security requirements.

How you install a certificate depends on the type of server and the type of certificate. Read the instructions provided by the certificate authority carefully and follow them correctly.

In Japan, many hosting services make it easy to enable HTTPS for free by providing certificates such as Let’s Encrypt. If you are about to choose a server, selecting one with that kind of support will make adoption much easier.

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Why redirects from HTTP to HTTPS are important

After moving to HTTPS, it is extremely important to redirect users who arrive through HTTP automatically to the HTTPS version. Without this setting, users who access an old HTTP URL may see security warnings or fail to load the content properly.

Redirect settings are handled in files such as .htaccess or in the server configuration itself.

★ The complete redirect guide: improve SEO, avoid risks, and master 301/302 setup

Steps for enabling HTTPS in WordPress

If your website runs on WordPress, you can usually enable HTTPS with the following steps.

1. Obtain and install an SSL/TLS certificate.
2. Change the site address to https:// in the WordPress settings screen.
3. Replace URLs inside the database with https:// values. A plugin is usually recommended for this.
4. Add FORCE_SSL_ADMIN to wp-config.php so that the admin screen also uses HTTPS.
5. Fix mixed-content issues.

Important points for enabling HTTPS in other CMS platforms

Even when you use another CMS, the basic HTTPS migration steps are similar. Check the official documentation for the CMS to confirm the exact setup procedure.

Cautions and troubleshooting after migrating to HTTPS

Once the migration is complete, it is important to confirm that the site works correctly and that no problems remain. This chapter explains the issues that can occur after moving to HTTPS, how to respond to them, and the maintenance that should continue afterward.

What to do when HTTPS connections do not work

If you cannot access the website after migrating to HTTPS, check the following points.

• Validity of the SSL/TLS certificate: Check whether the certificate has expired and whether it is installed correctly.
• Server settings: Confirm that the server configuration does not contain mistakes and that the HTTPS settings are applied properly.
• Firewall settings: Make sure HTTPS communication is not blocked. Port 443 needs to be open.
• DNS settings: Confirm that DNS changes have propagated correctly.

Common HTTPS errors and how to resolve them

Here are several common HTTPS-related errors and the usual ways to solve them.

• NET::ERR_CERT_COMMON_NAME_INVALID: This happens when the domain name on the SSL/TLS certificate does not match the site’s domain. Reissue the certificate or review the configuration.
• NET::ERR_CERT_AUTHORITY_INVALID: This occurs when the certificate was issued by an untrusted certificate authority. Obtain a certificate from a trusted CA.
• SSL_ERROR_RX_RECORD_TOO_LONG: This usually indicates a server-configuration problem. Review the server settings carefully.

What mixed content is, why it matters, and how to fix it

After moving to HTTPS, if part of the website still loads over HTTP, that state is called mixed content. When mixed content exists, browsers may show security warnings or fail to display the page correctly.

To fix mixed content, you need to change every HTTP resource inside the website to HTTPS. Review all URLs for images, scripts, CSS files, and other assets and update each one.

Google has also warned about this risk and has taken steps to block mixed content progressively.

When mixed content is loaded, the page ends up in an ambiguous state that is neither fully secure nor fully insecure, and that creates confusion in the browser’s security user experience.

Beginning with Chrome 79, Google started a process of gradually moving toward blocking all mixed content by default.

Breaking up with HTTPS mixed content

Site maintenance after moving to HTTPS

Even after a site has been moved to HTTPS, regular maintenance is still necessary.

• Renew SSL/TLS certificates: Certificates have expiration dates, so you need to renew them before they expire.
• Keep security measures in place: HTTPS is not the whole of security. Continue periodic security checks and software updates so that the website remains protected.

Frequently asked questions about HTTPS

Does migrating to HTTPS cost money?

If you use a free SSL/TLS certificate such as Let’s Encrypt, the cost of enabling HTTPS is essentially zero. If you choose a commercial certificate, however, costs will apply.

Is HTTPS necessary for every website?

For websites that handle personal information or payment data, HTTPS is effectively mandatory. Even beyond that, HTTPS is recommended for every website because it supports SEO and improves user trust.

Will HTTPS slow down site speed?

HTTPS can make a site very slightly slower in some situations, but with modern technology the effect is usually negligible. In some cases, newer protocols such as HTTP/2 can actually improve site speed after a move to HTTPS.

Summary: run a website safely and confidently with HTTPS

This article explained HTTPS broadly, from the basic idea to concrete settings and the cautions that remain after migration. HTTPS is indispensable if you want to improve website security and earn user trust.

Use this guide as a reference, move your own website to HTTPS, and create a safer and more reliable environment for everyone who visits it.