DevOps Enginer
Free DevOps Tools
Small, single-purpose tools built for the questions DevOps engineers actually google at work — each one speaking the platform dialect (Kubernetes, GitHub Actions, EventBridge, AWS) instead of the generic case. Every tool runs entirely in your browser: no sign-up, no uploads, nothing stored. They are the companion utilities to the guides on this site, and each tool page links back to the guide that explains the topic in full.
Scheduling
Cron Translator
Paste one cron expression and get the correct syntax for Linux crontab, a Kubernetes CronJob, GitHub Actions on.schedule and AWS EventBridge — with a plain-English meaning, the next 10 run times in UTC and JST, and warnings where a platform cannot express your schedule.
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AWS networking
AWS VPC Subnet Planner
Split a VPC CIDR into subnets across availability zones and see every subnet's CIDR, network, first/last usable address, broadcast and AWS-usable host count (total minus the 5 AWS-reserved addresses) — plus the free space left for future tiers.
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Kubernetes
Kubernetes YAML Checker
Paste a manifest and catch the production mistakes that pass kubectl apply: :latest or untagged images, missing CPU/memory requests and limits, missing probes, privileged containers, host namespaces and unset namespaces — with YAML syntax errors by line number.
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Why these tools exist
Generic converters answer the generic question. Production pain is specific: GitHub Actions runs cron in UTC and never faster than five minutes; EventBridge renumbers the days of the week; AWS quietly keeps five addresses in every subnet; a Kubernetes manifest can be perfectly valid YAML and still be a 3 a.m. page waiting to happen. These tools encode those platform-specific facts at the moment you need them.
More tools are added only when a guide on this site keeps answering the same question in prose — the blog is where the full explanations live, and the tools are the fast path through them.