Setup
Region and z-scores
Probability controls
Switch the question type, then move the cutoff values with the sliders or by dragging directly on the graph.
Classroom-ready examples
Jump to a common prompt with one click.
Predict, then check
Estimate the shaded area before reading the exact result.
Make a prediction, then compare it with the shaded region and exact probability.
Visualization
Normal curve and shaded region
Drag the shaded region or its cutoff lines to update the z-score directly from the graph.
The blue area is the probability requested by the current z-score statement.
In the between case, drag inside the band to shift both cutoffs together.
Area readout
The symbolic question and shaded probability update together.
Static and accessible fallback
All results are stated in text as well as shown graphically. Print this page or use Save as PDF; your instructor can also provide the equivalent static normal-table worksheet.