Announcing “Oh Dear!”: a new innovative tool to monitor your websites

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Mattias Geniar, February 24, 2018

Follow me on Twitter as @mattiasgeniar

We’ve just completed our first month of public beta at Oh Dear!, a new website monitoring tool I’ve been working on for the last couple of months with my buddy Freek. I’m excited to show it to you!

What is Oh Dear!?

Our project is called “Oh Dear!” and it’s a dead-simple tool you can use to help monitor the availability of your websites. And we define availability pretty broadly.

We offer multi-location uptime monitoring, mixed content & broken links detection and SSL certificate & transparency reporting. There’s an API and kick-ass documentation too.

Think of it as any other monitoring solution, but tailored specifically to site owners that care about every detail about their site.

What does it look like?

I guess the more obvious first question would be “what can it do?", but since we’re pretty damn proud of our layout & design, I want to brag about that first.

Here’s our homepage.

There’s extensive documentation on the API, every feature & the different notification methods.

A beautiful in-app dashboard to give you a birds-eye view of the status of all your sites.

An overview of the advanced notification features.

The whole design just looks & feels right.

If you’ve been following me for a while, you know I have no experience whatsoever with design. That’s why we got external help from an Antwerp web agency called Spatie to help layout our app. I couldn’t be happier with these results!

What can Oh Dear! do?

The heart & soul of Oh Dear! is about monitoring websites. So once you add your first site:

  • We will monitor its uptime from independent world-wide locations (downtime gets verified from another, independent location – different country, different cloud provider).
  • We validate its HTTPS health: certificate expirations dates, invalid certificate chains, revoked certs, certificate transparency reporting, …
  • We crawl your site and report any broken links (internal & external) and will report errors (like HTTP/500) to you
  • Everything can be reported to you via HipChat, Slack, Email, Push notifications (Pushover) or SMS (Nexmo)
  • There’s an API to automate Oh Dear! from start to finish & webhooks to tie in to your own monitoring systems

All of this in _– but I’m biased here – _the easiest interface to set this up. Everything is tailored to website developers or maintainers. Web agencies or large firms, that run multiple sites. We know & feel the pain involved in managing those sites, we built Oh Dear! specifically for that use case.

If you have clients or users that can create their own pages in a CMS, create links to other pages, … you’ll eventually get a situation where a user makes an unforeseen error. Oh Dear! can catch those, as we crawl your site and report any errors we find.

Can I try it for free?

Yes, a no-strings-attached, no credit card required free trial. Head over to Oh Dear! to give it a try.

The trial lasts for 10 days, we’ll bug you twice to give a heads-up that your trial is about to expire and then we leave you alone.


Give it a try & let me know what you think, what bugs you found or what features you’re interested in.

It’s already pretty feature-complete, but new code is deployed on a weekly basis and it contains a lot of good new ideas that have been reported by our community.

In the next few posts I’ll detail how every check is performed and explain the technicals behind it.

Stay in touch via or via @OhDearApp on Twitter.

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