Meaning of percentage in image title

Image Analysis
#1

Whenever I load a jpeg image into image J the top part of the image says the file name, followed by a percentage in parenthesis. What does this percentage (like 25%) mean? Thanks so much!

#2

Hello Christine.

ImageJ will scale image windows to fit them nicely on your screen, try clicking + or - on your keyboard with the image selected and you will see this number change.

Note that measuring this box, which is the same for both pictures, will give identical results.

See:

538×569 267 KB

and:

707×737 259 KB

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