Enter the original dimension and resize ratio into the calculator to determine the new dimension. This calculator can also evaluate any of the variables given the others are known.

Pixel Resize Formula

The following formula is used to calculate the new dimensions of an image when resizing.

ND = (OD * R) 


  • ND is the new dimension (pixels) OD is the original dimension (pixels) R is the resize ratio (decimal)

To calculate the new dimensions of an image when resizing, multiply the original dimensions of the image by the resize ratio. The result will be the new dimensions of the resized image.

What is a Pixel Resize?

Pixel Resize refers to the process of changing the size of a digital image by adjusting the number of pixels. This can be done by either increasing (upsampling) or decreasing (downsampling) the pixel count. The quality of the resized image can vary depending on the resizing algorithm used. It’s important to note that upsampling can often lead to a loss in image quality as the software has to ‘guess’ the color values for the new pixels created.

How to Calculate Pixel Resize?

The following steps outline how to calculate the Pixel Resize using the formula ND = (OD * R).

  1. First, determine the original dimension (OD) in pixels.
  2. Next, determine the resize ratio (R) as a decimal.
  3. Next, use the formula ND = (OD * R) to calculate the new dimension (ND) in pixels.
  4. Finally, calculate the Pixel Resize.
  5. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

original dimension (OD) = 800 pixels

resize ratio (R) = 0.5