About Circuit Symbols

What the site covers

Circuit Symbols explains the symbols used in circuit diagrams. Each symbol is drawn in both US and IEC (international) style, with its terminals named and its meaning explained.

• The symbol chart shows every symbol on the site on one page, US and IEC side by side.
• Symbol pages cover one family each, such as the resistor, diode, transistor and relay, including the variants and the symbols they are often confused with.
• How to read a schematic covers nodes, junctions and labels, with practice circuits.
• Practice has short quizzes with an explanation for every answer, and the worksheets print on A4 or US Letter.
• The glossary defines the terms used across the site.

Who it is for

Students meeting circuit diagrams for the first time, people studying for an amateur radio licence, hobbyists building from a kit or a schematic, and teachers who want printable material for a class.

How it stays accurate

Every technical statement links to the published source it comes from: textbooks, university course notes and manufacturer documents, all listed on the sources page. The method page explains how the drawings are made, and reported mistakes are checked against a source and corrected.

Who runs it

Circuit Symbols is an independent site. It is not affiliated with IEEE, IEC or any manufacturer, and it has no affiliate links. If the site shows ads, they are served by Google and kept apart from the content: advertisers have no say in what the site explains.

Contact

Questions, corrections and reuse requests are welcome on the contact page.