How to Set Up HTTPS on Your Website
HTTPS is a protocol for transferring data using a cryptographic SSL connection. To configure it, you need to install a digital SSL certificate.
How to prepare your website for installing an SSL certificate
Before uploading the certificate, you need to:

1) Connect a domain using the How to Connect a Domain Name guide;
2) Disable the "HTTP → HTTPS" and "WWW → without WWW" redirects if you have enabled them before;
3) Disable the HTTPS and WWW schemes in "robots.txt";
4) Check whether the DNSSEC option on the registrar's website is enabled. If it is, disable it. You can use third-party services to check whether the option is enabled.
Connect the domain using the "How to Connect a Domain Name" guide.

Wait for about 24 hours for all DNS servers to update the information of the new IP.
An example of configuring a domain
Add two A-type records (for the main domain and WWW) and specify the IP address provided in the Site Settings.
After changing the IP for the domain, disabling the redirects, and waiting for 24 hours, you can connect the SSL certificate.

Go to the Site Settings → SEO → HTTPS settings.

Click "Manage" and move the toggle switch into the "ON" position to generate a free "Let's Encrypt" certificate.
Wait for 5-30 minutes. The certificate has been connected if see the "secure connection for this website is on" status.
Check whether the HTTPS version of the website works. If you want the website to open using only HTTPS, go to the Site Settings → SEO → WWW, HTTPS Redirects, and select the "Redirect from HTTP to HTTPS" option.
Important: The SSL certificate works only for the websites hosted by Tilda. Once you export the project, the certificate won't work, you need to install it on your server side.
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