ShackWiki is a free collection of tools for amateur radio operators and electronics builders. It started because the tools I needed in the shack were scattered across old pages, half of them broken on a phone, and few of them explained where the numbers came from.

I'm Mick, 2E0CPU. I've been licensed since 2010, and most of my time on the air is on HF, using voice and digital modes. My antenna builds include a magnetic loop, a Cobweb and long wires, so the antenna calculators here are the kind of tools I use myself.

How the calculators work

Each tool uses published formulas and manufacturer data, and every page explains the method so you can check it. Everything runs in your web browser, so nothing you type is sent anywhere.

Calculations give a starting point, not a guarantee. Height, ground, nearby objects and component tolerances all change real-world results, so always check with an SWR meter or antenna analyser before transmitting at full power.

Corrections and ideas

If you spot an error or want a calculator that isn't here yet, please get in touch.