Designing safe, comfortable stairs requires balancing the rise (height of each step) and run (depth of each step) according to building codes and ergonomic standards, since stairs that are too steep or too shallow can be uncomfortable or unsafe. This stair calculator helps you design a staircase by computing the number of steps, individual rise and run dimensions, and the total stair length (stringer length) based on the total height you need to climb and your target step dimensions. It's useful for DIY builders, contractors, and homeowners planning a staircase renovation or new construction, helping ensure your stairs meet comfortable and code-compliant proportions. Getting these dimensions right is critical for both safety and everyday comfort.