Stair Calculator

Related Calculators

Stair Calculator: Terminology, Building codes, and Calculation

Let's Understand the Stair Terminology

There are different types of Stairs. Now constructing a basic staircase may look simple. But it may look more challenging than it is. Constructing a staircase involves various parameters, calculations, and codes to build a stair. It ranges concerning length, width, and certain parts of the stair. In some cases, the door placement is also dependent on the Staircase. Like if the arc of the door should be on the stair or if it could swing above the steps slightly.

Now we will discuss some common terminology for building a staircase. Also, some building codes for stairs. The codes to build stairs may differ at a local level. A person constructing a staircase should consider the codes related to the region.

Stair Calculator

The common codes for building a staircase

Run or Tread

A run or a tread is a part of the stair. It is the part where one steps. The length is calculated from the outer edge. If present, the nosing is involved. The Rise and Nosing are involved in the tread. While the Run is calculated, the length of the last tread is not measured. While the nosing is present, it does not equal the Total tread length. The overhung by nosing is subtracted from the total Run.

As per the building codes, the minimum length of the thread should be 10 inches.


The Riser is the height of the step. It is measured from one step to the top of the next tread. It is not dependent on physical height. It excludes the thickness of the thread. The number of risers is used to determine the number of steps. It excludes the number of threads. Hence the number of risers is needed to comprise a staircase.

As per the building codes, the maximum height for a riser is 7.75 inches.


A nosing is a bump at the edge of the thread. It hangs above the Riser. All the steps do not contain a nosing. But in whatever cases or steps, a nosing is involved. It is included with the length of the tread.

The main aim of having a nosing is to provide extra support. It is where a person steps on and can conveniently keep their feet.

As per the common building codes, the nosing should contain a minimum length of 0.75 inches. The maximum length should be 1.25 inches.


It is the height measured from the top of the tread to the ceiling. As per the building code, a headroom should provide enough room for people to use the stairs. According to the codes, it requires more space compared to the average height of a person To allow the movement of large objects easily and effortlessly.

The Building code for stair headroom is 6 ft 8 inches.

Width of the Stair

It is measured from edge to edge of each tread. It should be perpendicular to the tread length. The measurements of the length of a stair are longer than the width. It is when rectangles are considered. In terms of stair width is the longer side. The Width of the Stairs should not include handrails.

As per the Building Codes, the stair width should be a minimum of 36 inches.

Handrails or Guardrails

A handrail is a railing that goes in an inclined way along with a stair. It is present for the users to hold or take support in ascending and descending manner. It is a building structure of a component system located near the open sides. It is present to elevate walking surfaces. The Handrail reduces the risk of falling on the lower Staircase from above. The Guard can include rails. It can be several other constructions like walls, half walls, or a bench. Remember, these constructions are a replacement for the Handrails or GuardRails.

The Building codes need guards for stairs. It should have a total rise of 30 inches above the floor. These guards must be at least 34 inches. The height is from the top of the tread. It must be between 34 and 38 inches and should be measured from the top of tread. The diameter should be between 1.25 inches and 2.675 inches.


It is a part to support the treads and even risers. Usually, there are three types of a staircase. There is one on both sides and one in the middle. Stringers are only sometimes visible. It is visible on stairs on the open sides. The Stringer is either cut on each step, in some places, uncut, or concealed on the edges of the treads.

How to Calculate parameters using the StairCase Calculator?

There are two versions of the Stair Calculator.

The Basic Version

It allows the person to either calculate the

One Run or Use Total Run.

Input the values of the Run with the inches in the first column.

Input the Total Rise with the Feet in the second column.

Now tap on Calculate

The Second is The Comprehensive Version

Again here, one can calculate

One Run or Use Total Run.

Similar to the Basic version, add the value of the Run in inches.

Add the values of the Total Rise in Feet.

Here is a comprehensive Calculator one gets the option to choose the Rise from

  • Fixed Rise or Fixed Number of Steps.
  • Step height
  • Thread(No tread or had tread)
  • Headroom (Restrictions or none)
  • Mount(Stringer Mount is Flush or Standard)

Now one can calculate and get gh3 total stair values using the Calculator.

Various Stair Formulas for Calculation

The Stair Calculator calculates the details values and parameters for the stairs. It is for both known and unknown values. However, there are certain formulas to calculate, and the Stair Calculator Algorithm utilizes the same.

  • A staircase with a standard or flushed amount. The equation calculates the Total Rise of the Staircase.

Nos of Stairs=Total Rise/ Rise.

  • To determine the Total Run of the Steps

Total Run= run ×Nos of Steps.

  • The Stair Stringer length is next and can be calculated using the Pythagorean Theorem.

stringer length^2= total run^2+Stringerheight^

  • The next is Stringer height, and the formula is

Total rise-Rise

  • The last is the angle at which the stair is inclined.

Angle=arcsin(Stringer ht/Stringer length)


The Stair Calculator is the best tool to determine various parameters for constructing stairs. The Stair Calculator can easily calculate the tread, Rise, Rise, Run, Width, height, Handrail, and other parameters. It makes it easy for a person to add the values and construct the stairs easily and correctly. All the factors like placing the foot on the steps, the height, and other factors are considered while measuring and constructing a staircase.

The Stair Calculator simplifies the process of measuring and constructing stairs by providing accurate values for tread, rise, run, width, height, handrail, and other essential parameters, ensuring a precise and hassle-free staircase construction.


Q. What is the common terminology to build stairs?

A. Some common terminology and codes involved in building stairs are listed below. Building codes and requirements differ at various levels. They are the Run Tread, Riser, Headroom, Width and height of Stair, Handrail, and Stringer. For a detailed understanding of the parameters, refer to the article above.

Q. What is the difference between Stringer and a tread?

A. There is various terminology invoked in constructing a staircase. The Stair Calculator uses various terms. Let's understand the difference between Stringer and Tread. Tread: It is the horizontal part of the stair you step on. Stair Stringer: It is the construction on which the steps are mounted.

Q. How do you Calculate the height/Rise of the stairs?

A. TTo determine the distance between the steps and the floor. Divide the height by the number of the tread. Hence it produced the exact height of the stairs.

Q. What is the Total Run?

A. It is the Horizontal length of a stair stringer. It is the calculation of the number of threads multiplied by Tread Depth.

Q. What is the standard height as per the Building Code?

A. Per the Building code, the ideal or standard stair height is between 7-⅞ inches.