Enter the child element width (px) and the parent element width (px) into the Calculator. The calculator will evaluate the Responsive Percentage. 

Responsive Percentage Formula

RSP = CEW / PEW *100


  • RSP is the Responsive Percentage (%)
  • CEW is the child element width (px)
  • PEW is the parent element width (px)

To calculate the Responsive Percentage, divide the child element width by the parent element width, then multiply by 100.

How to Calculate Responsive Percentage?

The following steps outline how to calculate the Responsive Percentage.

  1. First, determine the child element width (px). 
  2. Next, determine the parent element width (px). 
  3. Next, gather the formula from above = RSP = CEW / PEW *100.
  4. Finally, calculate the Responsive Percentage.
  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.

child element width (px) = 200

parent element width (px) = 1800