Adding domains

Go to Domains → Add domain. Only the hostname is required; you can change everything else later.

The form

Hostname

The name to connect to, e.g. example.com or api.example.com. Leave out https:// and any path. The hostname cannot be changed later — to monitor another name, add a new domain.

Port

443 by default. Any port that serves TLS works:

Service	Port
HTTPS	443
IMAPS / SMTPS / POP3S	993 / 465 / 995
SMTP submission / SMTP / IMAP / POP3 (with STARTTLS)	587 / 25 / 143 / 110
Anything else	1–65535

Add a mail server just like a website: mail.example.com, port 587. CertWatchr picks the right protocol from the port number. If a mail service runs on an unusual port, the check reports STARTTLS upgrade failed.

Label

Optional, up to 128 characters. A readable name shown next to the hostname in every table and alert — "Acme – shop", "staging", "internal admin".

Tags

Optional, comma-separated, up to ten: prod, customer-a, web. Upper and lower case and the order do not matter. Click a tag in the domain list to show only those domains.

Alert threshold (days before expiry)

How many days before expiry the first warning arrives:

Days left	Status	You get
More than the threshold	OK	Nothing
Within the threshold	Warning	An expiry warning
7 or fewer	Critical	An expiry critical alert

On Free the threshold is fixed at 30 days. On Starter and Pro you choose 1 to 365 days — shorter for certificates that renew automatically, longer when a renewal needs a purchase order.

Also alert on certificates for subdomains

Starter and Pro, off by default. Normally CT log monitoring only reports certificates for this exact hostname and wildcards that cover it. Tick the box to hear about every name below it too, such as shop.example.com under example.com. Good for watching a whole domain; noisy on a large one.

Check frequency (on the edit page)

• Daily — the default.
• Weekly — once every seven days.
• Custom (Pro) — a cron expression, e.g. 0 6 * * 1-5 for weekdays at 06:00 UTC.

After you save

1. The first check runs about two minutes later.
2. The domain's page then shows the issuer, expiry date, days left and status. On Starter and Pro, the health score follows shortly after.
3. From then on, the certificate is checked on your schedule.

Host not reachable? The status turns to Error at once, but the check failed alert only goes out if the problem lasts about half an hour. A short network hiccup does not e-mail you.

Editing a domain

Open the domain and click Edit. You can change the port, label, tags, alert threshold, subdomain option and check frequency. To change the hostname, delete the domain and add it again.

Finding a domain

The filter bar above the list combines three filters, and they stay while you page through:

• Search — any part of the hostname or label.
• Status — OK, warning, critical, error or untested.
• Tag — one tag.

Import and export

Starter and Pro. Both are in the menu next to Add domain.

Export as CSV downloads all your domains, including the latest check results.

Import from CSV takes a file with a header row. Only hostname is required. port, label, tags, alert_at_days, check_frequency and check_cron are used if present; other columns are ignored. So an exported file imports straight back.

hostname,port,label,tags,alert_at_days
example.com,443,Main site,"prod,web",30
api.example.com,8443,API,prod,14

A bad row does not stop the rest. Afterwards you see which rows had an invalid hostname or port, which domains you already monitor, and which rows were duplicates. Your plan still applies:

• the import stops at your domain limit,
• a threshold outside your plan's range is adjusted,
• a custom schedule becomes daily on Free and Starter.

Files can have up to 1,000 rows.

Plan limits at a glance

Plan	Max domains	Alert threshold	Custom schedule
Free	3	fixed at 30 days	–
Starter	50	1–365 days	–
Pro	unlimited	1–365 days	✅

Everything per plan: Plans & limits.