A vertical intercept is a point where a line crosses the vertical axis, or y-axis, on the Cartesian coordinate plane. When evaluating a function, the vertical intercept can be found by setting the input, or x value, to zero.
A common example of a vertical intercept in math is found in the slope intercept equation of a linear function. The slope intercept formula is y = mx + b, where m is the slope of the line, b is the vertical intercept, and x and y are the ordered pairs found along the line. The slope intercept form is convenient to work with because the y variable is isolated to one side.