Photo File Sizes

The size of a file stored by a computer is measured in bytes. Since a byte is a tiny piece of information, eg a character in a document or a dot of colour in a photo, there are usually thousands of them in a file so we usually end up talking about kilobytes (kB), ie 1000 bytes, megabytes(MB), ie 1,000,000 bytes or even gigabytes (GB), ie 1,000,000,000 bytes.

The size of a file which stores a digital photo may be anything from a few kilobytes to many megabytes depending on the size and quality of the image. For example, the size of this small, black and white image:
is 20 kilobytes, whereas this large image:

is around 2.5 Megabytes, ie 2,500 kiloybytes.

More about photo quality, resolution and file size.

Storage Capacity

The capacity of anything which can be used to store computer files, eg hard drives, memory sticks, camera memory cards and DVDs, is also measured in bytes, or more usually megabytes or gigabytes.

The table below shows how many digital photos of various sizes could be stored on typical storage devices.

Average photo size (kilobytes) 250 500 1000 3000 5000
Photos stored on a 1GB memory card 4000 2000 1000 333 200
Photos stored on a 4.7GB DVD 18800 9400 4700 1567 940