AI-assisted: I drafted this from the Linux Foundation's exam pages and FAQ and used an AI tool to edit it. I run LearnSome.tech, where we have CKA and CKAD courses; you can make this decision without them.

People ask "which is harder?" The more useful question is "which one looks like my job?" Here is why.

The format is the same

Both are online, proctored, performance-based exams: around 15 to 20 tasks solved on the command line, on Linux hosts with kubectl already set up (with the k alias and Bash completion). Both give you 2 hours, both need 66% to pass, and each costs USD 445 including one free retake. Neither has a prerequisite. Both certifications are valid for 2 years.

So difficulty comes down to which tasks feel further from your day.

The work is different

The CKA is about running the cluster. Its heaviest domain is Troubleshooting at 30%, then Cluster Architecture, Installation and Configuration at 25%: kubeadm, upgrades, RBAC, a highly available control plane.

The CKAD is about the apps on the cluster. Its heaviest domain is Application Environment, Configuration and Security at 25%, with Design and Build, Deployment, and Services and Networking at 20% each: building images, probes, rolling updates, ConfigMaps and Secrets.

A CKA-style task:

# "worker-1 is NotReady. Make it Ready, and keep it Ready after a reboot." kubectl describe node worker-1 # conditions and taints first ssh worker-1 sudo journalctl -u kubelet -n 50 # why the kubelet stopped sudo systemctl enable --now kubelet # fix it and make it survive a reboot

A CKAD-style task:

# "The web app in namespace shop is Running but gets no traffic. Fix it." kubectl -n shop get pods,endpointslices # Running pods, empty endpoints kubectl -n shop describe pod -l app=web # readiness probe on the wrong port kubectl -n shop edit deployment web # fix the probe, then verify endpoints

The decision

  • You mostly ship apps to a cluster someone else runs: CKAD first.
  • You build images and write manifests: CKAD first.
  • You upgrade, repair or secure clusters and nodes: CKA first.
  • The CKS is your goal: CKA first, because the CKS requires a passed CKA.
  • Not sure: look at the last ten tickets you closed and count which list they fit.

If you plan both

They overlap more than people expect: rolling updates, ConfigMaps and Secrets appear in both curricula. Book the second exam soon after the first, while that shared ground is fresh, and spend the new study time on what the first one didn't cover.

One honest caveat: passing either shows you can do the tasks under time. It doesn't replace running clusters or apps in production.

Which one did you take first, and would you choose the same again?