When to upgrade to hourly SSL checks (25 domains)

Ssl monitoring 25 domains on an hourly schedule is the practical upgrade point when three daily watches no longer cover every revenue hostname and you need Slack-ready alerts before Monday standup.

Small platform and marketing teams hit this ceiling after adding staging, checkout, API gateways, and regional vanity hosts. Spreadsheets still list one expiry per brand while four public names each terminate TLS differently. The Starter tier exists for that inflection—not for enterprise theater.

The mistake is waiting for a customer-reported browser warning before you admit the free cap is a pilot, not an operations model. Hourly handshakes on twenty-five names cost less than one hour of checkout downtime and far less than rebuilding SEO trust after a silent lapse.

This guide explains what changes when you move from three daily domains to 25 hourly watches, how to prioritize which hostnames earn a slot, and how external probes complement ACME on the origin.

What you are actually buying

Upgrading is not purchasing certificates—it is purchasing scheduled live TLS probes and alert routing at a scale your incident culture can absorb.

A 25-domain hourly plan means each enrolled hostname gets an external handshake about once per hour. The monitor reads the certificate the internet receives: issuer, SAN coverage, chain trust, and expiry. That is the same measurement philosophy as test ssl online, repeated on a clock you do not maintain.

Daily polling on a free tier is honest for brochure properties. Hourly polling matters when deploy pipelines run Friday night, when CDNs publish edge material independently of origin renewals, and when mobile apps pin API subdomains you forgot to list in the sprint doc.

Plans should also surface domain registration expiry through RDAP where registries publish end dates. TLS and registrar clocks stay independent; both belong in a portfolio once you exceed a handful of brands.

At twenty-five names you are usually crossing from “founder memory” to shared on-call. The purchase is as much about webhooks into Slack or Discord on paid tiers as about the fourth hostname slot on a free plan.

Evaluation checklist

Use these ten criteria when ssl monitoring 25 domains is on your shortlist—not as generic feature bullets, but against your real architecture diagram.

1. Hard domain cap at 25. Transparent limits beat “unlimited” footnotes that throttle check frequency instead.
2. Hourly cadence stated plainly. Avoid “up to hourly” language that hides multi-hour gaps during incidents.
3. Live TLS per hostname. Each row must open TCP with correct SNI, not infer expiry from a uploaded PEM.
4. Threshold ladder at 30, 14, 7, and 1 days. Renewal runway alerts should fire once per threshold per cycle, not spam after a successful renew.
5. Webhook channels on paid tiers. Engineering teams ignore shared inboxes; chat routing is part of the upgrade value.
6. Email on every plan. Executives and contractors still need mailbox copies even when Slack owns Sev-2.
7. RDAP registration dates. Label missing ccTLD expiry instead of fabricating Whois guesses.
8. No inbound agent requirement. External checks should work through public DNS only.
9. One-shot validation. A public check path lets you prove a hostname before you burn a portfolio slot.
10. Room to grow toward 100. You want a clear Pro step when client microsites push past twenty-five without a migration project.

Score vendors against hostname inventory you export from DNS and load balancers, not against marketing apex rows alone.

How ssldays fits

ssldays performs live TLS handshakes on each monitored hostname and tracks RDAP registration expiry where published. Alerts follow 30, 14, 7, and 1 day thresholds with email on all plans.

The free tier covers three domains with daily checks—ideal for proving external TLS on your primary brand. Starter raises the portfolio to 25 domains, moves checks to hourly, and adds Slack and Discord webhooks alongside email. Pro supports 100 hostnames at the same hourly cadence.

That ladder maps directly to ssl monitoring 25 domains: stay free while you validate the workflow on a trio of production names; switch to Starter when inventory, incident urgency, or chat routing demands hourly signal across a mid-size fleet.

Validate any candidate hostname immediately via ssldays free check, then promote the same names into scheduled watches after signup. Pair enrollment with monitor SSL certificates for multiple websites inventory hygiene so staging and API hosts do not hide off the list.

Common mistakes when choosing a monitor

Upgrading before you list hostnames. Buying twenty-five slots while still monitoring only the marketing apex wastes money and breeds false confidence.

Treating twenty-five as “unlimited for us.” SAN-heavy SaaS quickly consumes slots when every customer vanity domain needs its own handshake row.

Assuming hourly checks replace reload discipline. Monitoring catches presentation drift; you still own Certbot, ACME, and CDN attachment workflows.

Skipping webhooks after upgrade. Paid plans fail when alerts land in a test channel nobody watches during PTO.

Counting wildcard coverage as one hostname in your head. One cert can cover many DNS names, but each public name users type may still need its own external probe—see monitor apex and www separately.

Ignoring registrar risk once TLS is automated. Domain auto-renew failures still take sites offline with valid certs on disk.

Next steps

Export every public hostname from DNS, CDN consoles, and mobile app configs. Run each through the live check and compare served expiry to your spreadsheet.

If more than three names matter for revenue or compliance, register for Starter and route one webhook into the channel that already receives deploy notifications. Run a full renewal cycle before bulk-importing the rest so you can tune alert noise.

Read daily vs hourly SSL certificate checks when stakeholders challenge whether hourly spend is justified, and how many domains you need to monitor before you size the next plan tier.