Expirity
Klaxel
ZoneWatcher
Domain-Monitor.io
UptimeRobot
Oh Dear!
Expiration Reminder
Free Domain Alerts
Cert Decoder
Expirity checks domain expiry (RDAP/WHOIS), full DNS record sets, nameservers, and SSL certificate status on a schedule (daily on the free tier, near-real-time on paid), and writes a change log every time something differs from the last check - registrar change, NS change, new/removed DNS record, cert reissue, etc. Alerts go out by email, Slack, Discord, or WhatsApp. There's a REST API and CSV/Namecheap/GoDaddy/Route 53 import if you're bringing in an existing portfolio.
Cert Decoder is a free online tool that helps you decode X.509 SSL/TLS certificates in PEM format. It instantly shows important information like the issuer, expiry date, SAN entries, and fingerprint. All data is processed locally in your browser, so nothing is ever sent or stored elsewhere.
Expirity Cert DecoderExpirity's answer
Domain and DNS problems tend to be invisible until they're urgent - a registrar warning email lands in spam, an auto-renew fails silently, or a compromised registrar account gets its nameservers swapped without anyone noticing until email stops working. Expirity was built to close that gap: continuous monitoring of expiry, DNS, and SSL status with alerts the moment something changes, rather than relying on a reminder email that might never be seen.
Cert Decoder's answer:
I built certdecoder.com over the weekend for my own needs. Sometimes in my work, I need to verify and check certificate details.
Cert Decoder's answer:
certdecoder.com was built using just JavaScript and HTML—simple, fast, and with all processing happening locally in your browser, so no certificate data is sent to any server
Expirity's answer
Agencies and MSPs managing domains across multiple clients, plus freelance developers and small businesses monitoring their own portfolios. The common thread is anyone responsible for a domain going down, a cert expiring, or DNS getting silently changed - and who can't afford to find out from a client's phone call.
Cert Decoder's answer:
certdecoder.com is primarily built for developers, sysadmins, cybersecurity enthusiasts, and DevOps engineers.
Expirity's answer
Most domain-monitoring tools are either built for individuals (generous on price, no multi-client structure) or built for MSPs (client folders and RBAC, but starting around $99/mo with no free tier). Expirity sits in between: a genuinely useful free tier (50 domains, no credit card), and a Pro/Agency structure ($19-$49/mo) that adds client folders and team roles without the higher price floor competitors in the MSP-focused space charge. Registrar import (Namecheap, GoDaddy, Route 53) also means bringing in an existing portfolio takes minutes, not manual entry.
Cert Decoder's answer:
Simple, fast, and reliable. Some similar tools can’t even decode basic certificates. I rigorously tested my tool with many real-world certificates and covered several edge cases where competitors fall short.
Cert Decoder's answer:
certdecoder.com is primarily built for developers, sysadmins, cybersecurity enthusiasts, and DevOps engineers.
Expirity's answer
Expirity combines domain expiry, full DNS record monitoring, nameserver/registrar change detection, and SSL certificate tracking in one tool - instead of stitching together WHOIS reminders, a separate SSL checker, and a PSA workaround. For agencies and MSPs specifically, it adds client folder organization, per-client alert routing, and role-based team access (admin/editor/viewer), so one account can manage domains across many clients without exposing them to each other.
Based on our record, Cert Decoder seems to be more popular. It has been mentiond 1 time since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
Why? Because I built certdecoder.com and couldn’t find a decent place to submit it. So I said screw it — I’ll build my own. With blackjack and hookers. - Source: dev.to / over 1 year ago
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