Free Home Server Tools
Ten calculators and converters that answer the questions every home server owner runs into: power draw, RAID maths, Docker, permissions, networking and how long that copy will actually take. Everything runs in your browser — no sign-up, nothing sent to a server.
Home Server Power Cost Calculator
What your server costs in electricity per day, month and year.
RAID & Redundancy Calculator
Usable capacity and fault tolerance for RAID 0, 1, 5, 6 and 10.
Chmod Calculator
Turn read/write/execute checkboxes into an octal chmod command.
Crontab Translator
Paste a cron schedule and read it in plain English.
Docker Run to Compose Converter
Convert a docker run command into a docker-compose.yml.
Media Storage Calculator
How many TB your movies, shows and photos actually need.
Subnet & CIDR Calculator
Network, broadcast and usable host range for any IP and CIDR.
Default Port Search
Look up the default port of any self-hosted app, or the other way round.
File Transfer Time Calculator
How long a copy takes over Ethernet, WiFi or Tailscale.
Password Generator
Strong random passwords generated locally, with an entropy score.
Why these tools are free — and stay in your browser
These are the calculators I kept re-writing for myself while building my own home server, so I turned them into proper tools. They are plain HTML, CSS and a little JavaScript: there is no account, no server-side processing, and no input ever leaves your browser.
Want the context behind the numbers? Every tool links to the guides that go with it — start with choosing hardware or the Docker installation guide.