# Decimal to binary conversion calculator

Computers are digital devices. This means that all the images and words that computers display are stored as ones and zeroes. A one is stored as a tiny electric charge. A zero is represented by an absence of electric charge. Each one or zero is a ‘bit’ of information (computer transmission speeds are described in bits per second). A group of 8 bits together is called a ‘byte’. A byte holds enough information to code a single letter or number. Multiples of a byte (such as kilobytes, megabytes and gigabytes) are used to describe storage capacity.

It can be a slow process to convert the decimal numbers we use every day into binary. Make a conversion calculator that will automatically convert decimal to binary.

How to convert

Before you start making your automatic converter you need to know how to change decimal to binary numbers. Review the process by working through this Binary numbers (.pptx 324kB) PowerPoint presentation.

Explore the calculator

Open the Converter (.xlsx 9kB) Excel spreadsheet to explore the beginnings of your conversion calculator. Open Decimal to binary – Exploring the calculator (.docx 26kB) for instructions. Work with a copy of the calculator and save as you change it.

Enhance your calculator

At present the largest digital number you can convert to binary with your calculator is 15. You will be extending the largest number to 255 by adding four extra columns of formulae to the spreadsheet in columns D to G. Open Decimal to binary – Enhancing the calculator (.docx 26kB) for instructions.