Determining Aspect By Hand

We get it. Math is hard. Use our online ratio tool to get the information automatically.

Ratios rely on one simple fact: they are always reducably equal. Images with a ratio of 4:3 could include those that are 400x300, 800x600, 200x150, etc.

4:3 Ratio Example

The Equations

Determining Height: (Original Height × New Width) /  Original Width = New Height
Determining Width: (Original Width × New Height) / Original Height = New Width

An easy way to remember the order is "Criss-cross multiply divide." This is easiest if the dimensions are written out as ratios.