I want to calculate the size of a layer area in centimeters using photoshop. Is there any tool to do so rather than the ruler? The layer I need to calculate the size of its area doesn't have a proper shape.

I asked my question in stackoverflow and received this answer:


The info page in photoshop gives me the maximum height and width of the layer I select. so when my layer has a random shape, these numbers can't help me calculate the area size.

I don't have enough reputations to upload the picture, so please open the above link.

  • 1
    The "layer" itself always rectangular, even if the objects draw on it are not. Since Photoshop isn't vector or object based, it doesn't really know anything about the things you drew. Sep 30 '11 at 18:12
  • when the shape is irregular, area does not make any sense anyhow. Why do you need area?
    – hk_
    Sep 30 '11 at 20:04
  • @Dave: In agriculture the area size of a leaf is an important factor for analyzing the quality of a plant. So I want to know if it's possible to scan the leaves and determine their area size using photoshop. Oct 1 '11 at 20:55
  • Photoshop is not a math, engineering or CAD program. It's not designed for things like calculating the surface area or volume of shapes you draw. This type of problem is more suited to Mathcad or Mathematica. Otherwise, if you just want a rough estimate, you can simply use Photoshop scripting to convert pixels to cm^2 (centimeters is a measure of length). May 3 '12 at 2:49

It would be wonderful to be able to do this automatically by having say, the lasso tool display that property, but I haven't been able to find a graphics program that gives that data.

What I have had to do is manually enter the X,Y coordinates if the polygon vertices into an Excel spreadsheet and use that to calculate the area in pixels. Needless to say it is a tedious process.

Any other suggestions would be welcome.

search tags:- How to calculate the area of an irregular polygon on an image. How to find the area of an irregular polygon on an image.


Two software solutions:


You have to use the ruler tool and check the info palette - it will show you the value.

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Click the "+" icon. It will show you some options and then select Centimeters.

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Use Histogram window in Photoshop (click on "extended view"). In the lower left corner you'll find the number of pixels of your selection. Look at this image for reference:

enter image description here

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