Skip to content Request a project consultation

1 minute security check · 004 security SSL HTTPS

I personally saw the locks of 285 domestic websites.

Approximately 4 minutes to read BlueCanvas

How do I check if my website's SSL certificate is properly installed?

You can click the lock in the address bar to see the expiration date, and try opening it with an address with www and an address starting with http. As a result of directly checking 285 domestic locations, 63 were opened without encryption, and 27 did not pass browser verification even though they had certificates.

Key takeaways

  • Domestic website 285 placesI accessed directly and verified the certificate. Of the 273 that responded 63 placesThis opens without encryption.
  • Even if the certificate is hanging 27 placesdid not pass browser validation. There are 13 missing intermediate certificates, 7 self-signatures, and 5 address mismatches.
  • 17 placeshave certificates expiring in 30 days, four of them have less than a week left and two have already passed.

The lock in the address bar is not for decoration.

Without a lock, three things happen at once.

  • to visitors “Caution required” warningappears first. See a warning before viewing the company profile.
  • The entered value is without encryption It comes and goes. The contact information you entered in the inquiry form will be passed as is.
  • Google uses HTTPS ranking signalIt is stated in the official document that it is written as .

I opened 285 locations today.

I did not cite anyone else's research. This value was measured through direct access on August 30, 2026. BlueCanvas review archiveFrom (2,595 cases), 641 sites with target site addresses remaining were selected, and among them, domestic domains (.kr), the target is 285 places.

Of these, 273 responded.

63 locations open without encryption

When you enter the http address, it opens directly instead of going to https. 63 placesIt was. This is 23.1% of the 273 places that responded. That's about one in four places.

This often happens because even after purchasing a certificate, you do not configure http to https. Visitors who enter by manually entering the address will continue to see an unencrypted screen.

Even though the certificate is hanging, it doesn't pass

443 out of 266 ports open 27 placesThis browser verification failed. The reasons are as follows.

reasonplacedetail
Missing intermediate certificate13 placesSend only one leaf certificate to the chain. Even though it works on PC browsers, it is blocked on some mobile devices and apps.
self-signature7 placesAll issuers My Company Ltd It was. The default values ​​were left as is during installation.
address mismatch5 placesSince the addresses written on the certificate are different, a warning appears only for addresses with www added.
Expiration/Key Length Insufficient2 places

Missing intermediate certificates are less noticeable. Here, a situation arises where it appears normal on the person in charge's PC, but a warning appears only on the customer's mobile phone.

17 locations will be completed within 30 days

The certificate has an end date. Free certificates have a short renewal cycle, usually 90 days.

  • 17 places — Expires in 30 days.
  • 4 places — Less than a week left.
  • 2 places — It has already passed.

Even if automatic renewal is enabled, if the web server is not reloaded after renewal, the old certificate will be served as is. Not whether it has been updated or not Is the certificate the browser sees new?You must check .

How to check right now

  1. in the address bar press the lock View the certificate validity period.
  2. Address with wwwOpen it again with . In this investigation, warnings were issued only at five addresses.
  3. Address starting with httpEnter to check if it goes to https.
  4. Open it on your phone as well. The missing intermediate certificate is revealed here.

In many cases, it is not just the certificate that is the problem. To view overall server settings How to check if your website has been hacked in 10 secondsclass Server security auditPlease continue to check.

The domain used in the research is used both on screen and in the text to avoid pointing to a specific company. example.co.kr I changed it to .

Full video subtitles (6 scenes)

The lock is not decoration

The lock in the address bar is not decorative. If not, visitors will see a warning first. Google also announced that it uses it as a ranking signal.

I opened 285 places.

I personally opened 285 domestic websites today. Of the 273 that responded, 63 open without encryption.

Doesn't pass verification

27 failed browser verification. Seven places were still using self-signed certificates.

There is an end day

For 17 locations, the certificate expires within 30 days. Four of them have less than a week left. Two places have already passed.

How to check

Click the lock to see the expiration date. Also try opening the address with www. For five locations, a warning appeared only at that address.

We will take care of it for you

If BlueCanvas takes over maintenance, we will renew it before expiration. What does our company address bar look like now?

Frequently Asked Questions

Is it okay to use a free certificate?

it's okay. Browsers do not treat free and paid certificates any differently. However, the free certificate has a short validity period of 90 days, so automatic renewal is required. Make sure that even the step of reloading the web server after an update is automated.

It's normal on my PC, but the customer says a warning appears.

It is most likely missing an intermediate certificate. The PC browser appears to be normal because it retrieves the previously downloaded intermediate certificate from the cache. This can be solved by setting up a fullchain certificate so that the server sends the complete chain.

A warning appears only when www is added. Why is that so?

This is because the address with www added was not included when the certificate was issued. You can either enter both addresses in the issuance target, or create a redirect that passes one address to the other.

What do I need to do to change http to https?

In your web server settings, you can redirect requests coming through port 80 to 443 or 301. After that, if you add the HSTS header, the browser will connect to https from the beginning. However, since HSTS is difficult to restore, turn it on after confirming that https is operating stably.

We renew before expiration

When BlueCanvas takes charge of maintenance, it also checks certificate expiration, renewal, and reflection on the web server. You can first check what the current status is.

Take a look at website/server control
Website/Server Control (SOC) We constantly monitor certificate expiration and abnormal traffic and take proactive measures. AI server security inspection and diagnosis Over 30 items are checked, including SSL/TLS settings. Case Studio — Website Maintenance and Security We have outlined how security items should be included in maintenance contracts.

Other short form insights

Visual AI 는 이야기를 먼저 정리한 뒤 AI 로 장면을 만듭니다 숏폼 영상 표지

Introduction to BlueCanvas tools

Visual AI 는 이야기를 먼저 정리한 뒤 AI 로 장면을 만듭니다

영상 한 편을 만든다면 어디서부터 시작해야 할까요? 더블루캔버스 Visual AI 는 장면보다 이야기를 먼저 정리하고, 인물 35명을 하나씩 준비한 뒤 하나의 브랜드 영상으로 합칩니다. 영상 속 예시 이미지는 고객 사례가 아닙니다.

Learn more →
Use ImgView to flip through photos in folders and compressed files without unpacking them. Short-form video cover

Introduction to BlueCanvas tools

Use ImgView to flip through photos in folders and compressed files without unzipping them.

Does the program you open to view a single photo have to be heavy? BlueCanvas ImgView lets you move through folders with the direction keys and view images in compressed files without unzipping them. It's free with no ads or embedded programs.

Learn more →
Divide one-time expenses and recurring expenses into one column Short-form video cover

1 minute of practical work from the boss

Divide one-time and recurring expenses into one column

If you set next month's budget as this month's total, even the items you bought will be budgeted again next month. I added a column to classify the items and organized the order in which I look at every other month.

Learn more →

See all short form insights→