Installing an SSL certificate for a website is now a routine action, but if you have dozens of websites with SSL certificates installed at the same time, you may forget to renew a certain SSL certificate due to your own negligence. For some websites with very high application requirements, it will bring considerable losses.
In addition, many people use free SSL certificates such as Let's Encrypt. Naturally, there is no problem in running such certificates. However, one drawback is that the validity period is too short. Let's Encrypt only has a validity period of 90 days and expires every three months. It's easy to forget to renew Let's Encrypt once you have to renew it.
This article will share three free websites for online monitoring and expiration reminders of SSL certificates: LetsMonitor.org, certificatemonitor.org and keychest.net. These three websites will automatically analyze the website’s SSL certificate. Before the certificate expires, Email reminders will be sent every month, 15 days or 7 days, so that you have enough time to renew your SSL.
For more SSL certificate application and usage tutorials, here are:
- Collection and summary of free SSL certificates - add HTTPS secure encrypted access to the website for free
- Let’s Encrypt Wildcard free domain name SSL certificate one-click application and SSL usage tutorial
- Three online free SSL certificate application addresses: AlwaysOnSSL, SSL For Free and FreeSSL.org
PS: Updated on August 12, 2018, Website access using Https consumes more resources than HTTP access to a certain extent. Here are the optimization methods: Eight HTTPS and SSL optimization usage experiences - reduce waiting time and reduce costs HTTPS performance loss.
1. All-round LetsMonitor.org
website:
- HTTPS://letsmonitor.org/
LetsMonitor.org is a free online website that monitors the validity period of SSL certificates and sends reminders. SSL certificate monitoring has always been the main business of LetsMonitor.org, but recently it has added various types of monitoring such as DNS, Web, HTTPS, etc., and has gradually developed into A comprehensive monitoring platform.
It is very simple to add SSL certificate monitoring to LetsMonitor.org. Simply enter the domain name of the website you want to monitor and set the expiration date. Then LetsMonitor will start monitoring from the default server.
This is the control panel of LetsMonitor, where you can see statistics such as SSL certificates and server online. (Click to enlarge)
The SSL certificate monitored by LetsMonitor will display the expiration time and will send you an email reminder before expiration.
2. Super simple certificatemonitor.org
website:
- HTTPS://certificate monitor.org/
It can be seen from the domain name of the website that certificatemonitor.org is a website specializing in SSL certificate monitoring. The website has only one function, which is 3 months, 2 months, 1 month, 14 days before the certificate expires. An email reminder will be sent to you on 7 days, 5 days, 3 days, 2 days, 1 day, etc.
Certificate Expiry Monitor is also very simple to use. You only need to enter the domain name you want to monitor on the website and then submit. Confirm via email and you're done.
3. Multifunctional keychest.net
website:
- https://canchester.net/
KeyChest is a multifunctional SSL certificate online monitoring website. In addition to monitoring the validity period of SSL certificates, it also monitors HTTPS/TLS online duration, SSL server security, and generates log reports.
This is the control panel of KeyChest.net. From here you can intuitively see data such as the expiration of the SSL certificate, security issues, and server configuration. (Click to enlarge)
4. Summary
LetsMonitor.org, certificatemonitor.org, and keychest.net monitor content with different focuses, but they can all be used as SSL certificate expiration reminder tools. The following is a comparison between the three of them:
| Features | letsmonitor.org | certificatemonitor.org | canchester.net |
| Key business | Website monitoring | Certificate expires | HTTPS/TLS online time |
| API | intend | none | have |
| port | 443 or customized | 443 | 443 or customized |
| Test object | server | server | Certificate transparency and servers |
| frequency | per hour | Not fixed | Varies with test type |
| E-mail notification | only once | 9 times in total | once a week |
| Monitoring points | 150 | Concentrate 1 | Concentrate 1 |
| Safety test | basic project | Certificate only | Multifunction |
If you have used the enterprise-level website monitoring tool Zabbix, you should know that Zabbix can also implement online SSL certificate expiration monitoring. For specific usage methods, please see: Zabbix installation and use - a powerful server performance monitoring tool to control server software and hardware resources.