Free DevOps Tools
Handy calculators and utilities for sysadmins and DevOps engineers. No signup required.
SLA Uptime Calculator
Calculate allowed downtime for any SLA availability target from 99% to 99.999%.
Cron Expression Generator
Build and validate cron expressions visually with human-readable descriptions.
Disk Space Calculator
Plan server storage with growth projections and retention policies.
MTTR Calculator
Calculate Mean Time To Recovery and compare against industry benchmarks.
Subnet Calculator
Calculate network address, host range, and usable hosts from any CIDR notation.
Load Average Interpreter
Enter your load average and CPU cores to get a plain English explanation.
Server Sizing Calculator
NewHow much CPU, RAM and disk does your workload need? Pick a workload, describe its shape, get a minimal and a comfortable spec.
Bandwidth Cost Calculator
NewCompare what a month of egress costs on AWS, Google Cloud, Azure, Hetzner, DigitalOcean, Linode, OVHcloud and Cloudflare R2, with the tier breakdown.
RAID Calculator
NewUsable capacity, parity overhead, fault tolerance and rebuild risk for RAID 0, 1, 5, 6, 10, 50 and 60.
Linux Package Vulnerability Scanner
Find unpatched CVEs in your installed Linux packages. Paste your package list, get a CVE report sorted by severity.
Linux Kernel CVE Checker
NewPaste one line of `uname -a` and see the CVEs against the kernel your server is actually booting, plus how old it is.
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