---
title: "LED Calculator"
description: "Rob 'linear' Arnold has put together a fantastic (http://led.linear1.org/led.wiz \"LED Wizard\"). Not only will it calculate the current limiting resistor you need, it will draw…"
canonical: "https://www.baldengineer.com/led-calculator.html"
author: "James Lewis"
date: "2010-10-13T11:44:05Z"
lastmod: "2015-03-24T16:24:07Z"
image: "https://www.baldengineer.com/wp-content/uploads/2010/10/Screen-shot-2010-10-13-at-8.35.30-AM.png"
categories: ["around-the-web"]
tags: ["calculators","electronics-basics","leds"]
---

# LED Calculator


Rob 'linear' Arnold has put together a fantastic [LED Series/Parallel Wizard](http://led.linear1.org/led.wiz "LED Wizard").  Not only will it calculate the current limiting resistor you need, it will draw a circuit diagram, and give you full statistics on power usage.  If you are just getting started with Electronics, this is a great resource for [learning about LEDs](/led-basics.html "LEDs: A tutorial on the basics").  Experienced users will enjoy a quick check of their math.

The array above is designed for some Blue LEDs I have laying around.  I wanted them to run with 15mA which is well below their max, but still very bright.  In this case 1/4W resistors should be fine and each should be 120 ohms.  I should be safe hooking this array up to an Arduino since each LED will draw less than each I/O pin can handle AND total current draw is only 60mA.

Very Cool Stuff!

[http://led.linear1.org/led.wiz](http://led.linear1.org/led.wiz)