Last updated: August 2026
Certline is a TLS certificate inspection tool. It opens a real TLS connection to a hostname you provide and reports the certificate the server presents: expiry date, issuer, subject alternative names, and chain completeness.
The service is provided as-is, with no uptime guarantee. Certline is a diagnostic tool, not a monitoring service. It does not send alerts, schedule re-checks, or store historical data.
The Free tier is available to anyone without an account, registration, or payment. There are no usage limits on individual hostname checks. The Free tier includes all current features of Certline.
What you buy. A Pro subscription grants access to the Certline API for CI/CD integration, dedicated infrastructure priority, custom port ranges, and any future Pro features listed on the pricing page.
Price. Pro is $19 per month, billed in advance. The price is fixed for the duration of your subscription. Any price changes will be announced at least 30 days before they take effect.
Billing period. Subscriptions are monthly, recurring automatically at the start of each billing period. You will be charged on the same day each month. There is no annual or multi-year option.
Failed payment. If a payment fails (card declined, expired, or insufficient funds), we will retry the charge automatically up to three times over a period of 7 days. If all retries fail, your subscription will be suspended. You will have 14 days to update your payment method before the subscription is cancelled. During suspension, Pro features will not be accessible, but your account data will not be deleted.
Refund policy. Refunds are issued at our discretion on a case-by-case basis. If you cancel within the first 7 days of a billing period, you may request a full refund for that period. After 7 days, no refund is given for the remainder of the billing period, but your subscription remains active until the end of the paid period. Refund requests should be sent to the contact address on the pricing page.
Cancellation. You may cancel your Pro subscription at any time. Cancellation takes effect at the end of the current billing period. No further charges will be made. There is no partial refund for the remainder of the billing period (except as described in the refund policy above).
No phone number, email address, or legal entity. These terms are provided as a statement of intent. Until a payment processor is connected, no purchases can be made and no billing relationship exists.
You agree not to use Certline to probe hosts without authorization, to enumerate subdomains or IP ranges, or to conduct any activity that could be construed as hostile reconnaissance. Certline checks one hostname at a time — automated bulk scanning is not permitted.
Certline is provided as a diagnostic aid. The certificate data reported is what the server presented at the time of the check. We make no guarantees about accuracy, completeness, or timeliness. In no event shall Certline be liable for any damages arising from the use or inability to use the service.
We may update these terms at any time. Changes will be posted on this page. For Pro subscribers, material changes will be notified at least 14 days in advance.