Ladder Height Calculator Chart: To Select Ladder Length You Need

This article is all about ladder height calculator charts that assist you in finding the right height ladder for your job.

You can’t deny that finding the ideal height ladder for any job is important and tricky to select.

In such circumstances, people often get confused and fail to choose the proper ladder for their job, which sometimes leads them to fatal accidents.

Because here, you need to consider several factors like ladder height, working height, your height, and ladder type.

So, we come here to help you to calculate the perfect ladder height and ideal ladder-type for your jobs.

Continue reading and gather proper knowledge.

Different Sort of Ladder height calculator charts

First of all, different types of ladders are used for different jobs. And obviously, each ladder height calculator chart is different.

So, to use any ladder safely, you need to acknowledge their distinctive height chart along with their maximum reach.

In the below section, we have listed different types of ladder height chart and their working area one by one.

Let’s get started with the step ladder.

1. Step ladder height chart

Starting with step ladder definition, this is a self-supported ladder design in A-frame layout. At the same time, both side rungs are locked with spreaders bars.

It is fixed in length, remains stable in place without support, is non-adjustable in feature, and is highly portable.

The maximum type of step ladder is meant to design for one person to use at a time. But two people can use a few ladders designs called twin step ladders.

Generally, a step ladder is mostly used for household courses for indoor work. For example: cleaning or repairing a ceiling, changing the bulb or curtain, painting the indoor wall, accessing the high cabinet, etc.

Interestingly, calculating the step ladder height is easier than another ladder.

In this case, one must keep in mind; the step ladder approximately needs 4ft of the work area for user safety to reach on working place and user safe stand on the rungs.

Not clear?

Take a look at the step ladder height chart to determine what height step ladder you need.


Ladder HeightMaximum Reach
4 Feet8 Feet
6 Feet10 Feet
8 Feet12 Feet
10 Feet14 Feet
12 Feet16 Feet
14 Feet18 Feet
16 Feet20 Feet
18 Feet22 Feet
20 Feet24 Feet

Now, for example, you need to work on a 10 feet ceiling from the ground, then you need a 6 feet step ladder. Similarly, if your working area is 12 feet from the ground, you need an 8 feet step ladder.

Meaning that you need 4 feet of working space in every height step ladder.

Although step ladders are safe in use, there are a few safety rules of step ladder you should follow for proper protection.

Remember few points

  • Never use the top three rungs of any step ladder
  • Make sure you place a ladder on stable ground
  • Never use a step ladder as a leaning or straight ladder
  • Always maintain 3 points of contact while on the ladder
  • Do not overload your weight with other accessories

Check out the step ladder reviews if you are looking for a step ladder.

2. Extension ladder height chart

Moving to the next category, a broadly used ladder name is extension ladder. Unlike step ladders, extension ladders require stable support to stand in place and design in a straight layout.

An extension ladder is built in two parts. One part is fixed and another is customizable and known as the flying part. Yes, extension ladders allow users to adjust the length according to user needs.

And this special feature makes this ladder most desirable. And fit it for the maximum type of professional work where users need to access higher height.

Along with warehouses and other industrial work, extension ladders are also fantastic for household work. For instance: cleaning gutters, reaching the rooftop, painting outdoor walls, and so on.

However, similar to the basic step ladder, an extension ladder is also designed for one person to use.

Now difficulty comes when you need to calculate extension ladder height as per your working height.

Feel tensed?

Don’t worry; we have an attractive solution for extension ladder height calculation. We have described the extension ladder’s main and maximum reach lengths with some extra advice.


Ladder HeightMaximum ReachHighest Point Ladder User Could Touch
16 Feet15 Feet9 Feet
20 Feet19 Feet9 to 13 Feet
24 Feet23 Feet13 to 17 Feet
28 Feet27 Feet17 to 21 Feet
32 Feet31Feet21 to 25 Feet
36 Feet34 Feet25 to 28 Feet
40 Feet37 Feet28 to 31 Feet

More clearly speaking, a 20 feet extension ladder can be highly measured as 18 to 19 feet. Because the extension ladder has 1-2 inches overlap among the base and fly parts.

Moreover, the extension ladder has to be placed against any solid construction. And there you need to follow a 4:1 ratio angle.

And for angle maintenance for every 4 feet working height, you need to place your ladder 1 foot away from the supporting wall.

For example, if you want to reach 15 feet height, you need an 18 feet ladder. Again, if your working height is 18 feet, you need a 21 feet ladder.

  • With that said, for any extension ladder project, a good rule is to measure 3ft extra length.

Well, an extension ladder length starts from 16 feet and mostly ends at 40 feet design.

However, extension ladders need support to stand on the ground. So you should follow a few basic extension ladder safety advice.

In addition, you must follow the ladder 4:1 ratio rule. See our How to Place Ladder with Proper Ladder Angle article for further information about placing an extension ladder base on the ground.

Don’t worry; it is very easy to learn, so be confident.

Remember few points

  • An extension ladder is featured with a 1-2 inches overlap between the base and fly section. So, you need to consider it at the time of height calculation. For example, if your ladder height is 16 feet, for the overlap, you get the maximum 14-15 feet working height.
  • It would be best not to stand on the top 3-4 rungs of any extension ladder.
  • When using the ladder on a gutter or rooftop, always extend at least 3 feet from the top.
  • Plus, when working on the rooftop and gutter with an extension ladder, don’t forget to tie off the ladder properly.
  • Most extension ladder accidents occur for wrong base placement. So carefully follow the ladder angle rule.

Don’t forget to check our latest extension ladder review and analysis.

3. Telescoping ladder height chart

Next to our list is a telescoping ladder similar to the extension ladder in terms of length adjusting.

However, telescoping ladders are more flexible than extension ladders. Since it allows the user to expand the ladder height exactly how much length the user needs.

But telescoping ladders have height limitations since most are designed in the highest 15 to 17 feet layout.

Therefore, it also needs support to stand on the ground. But it is not super strong in case of long height work like step and extension ladder.

However, telescoping ladders don’t bear two parts similar to an extension ladder. Rather, it has locking features that assist users in expanding the height and locking the section accordingly.

It is a good ladder when you need a little extra height than a step and less high height than an extension ladder.

More or less, it looks like a single, straight, or leaning ladder. But unlike other sorts of ladders, it has super portability.

Well, the telescoping ladder height chart is also applicable for the leaning, straight, or single ladder height calculation.


Ladder HeightMaximum Reach
6 Feet5Feet
8 Feet7 Feet
10 Feet9 Feet
12 Feet11 Feet
14 Feet13 Feet
16 Feet15 Feet

Remember few points

  • The telescoping ladder has no overlap like an extension ladder so, you don’t need to measure it like an extension ladder
  • If you work on a rooftop or gutter, then never tie off the ladder with anything tight than ladder weight
  • At the time of ladder base placement, maintain the ladder angle rule properly to avoid an accident.
  • Not all type of telescoping ladder is not good for heavy-duty work, so be careful

4. Multipurpose ladder height chart

Besides step, extension, telescoping, and single ladder. Another popular type of ladder is the multipurpose ladder.

Since it is a multipurpose ladder, it has no exact form and length. Users customize its type and length according to their needs.

In this stage, the multipurpose ladder has no fixed height chart. When you use this ladder as a step ladder, you need to follow a step ladder height chart.

Further, you have to follow the extension ladder height chart when you use this as an extension ladder.

The multipurpose ladder has many advantages and few limitations. Better read one detailed review of this type of ladder.

Consider These Ladder Safety Tips While Working on height:

According to Occupational Safety and Health Administration (OSHA). Every ladder user has to obey a few ladders safety tips. Take a look.

  • On the top, inspect ladder condition and check the ladder is in working condition. It is free from any damage; the locking mechanism works perfectly. It is free from rust, oil, dents, and others.
  • Before starting an outdoor project, check the weather. And never use the ladder in stormy or other bad weather situations.
  • Make sure you have placed the ladder base on stable ground.
  • Maintain ladder angle rule for ladder base placement
  • Always face the ladder while climbing up and down.
  • Wear safety shoes at the time of climbing
  • Always maintain 3 points of contact while on a ladder (except when you are on a platform ladder).
  • For electrical and powerline side work, use a fiberglass ladder because it does not conduct with electricity.
  • Try not to carry extra accessories with the hand; rather, use a ladder belt.
  • Do not overreach
  • It is recommended to avoid extra load than ladder allows weight capacity.

Check the ladder load capacity:

You should also follow ladder load capacity for safety along with the ladder height calculation.

Ladder TypeLoad CapacityBrief Description
TYPE-IAA375 IBSSpecial duty
TYPE-IA300 IBSExtra Heavy-duty
TYPE-I250 IBSHeavy duty
TYPE-II225 IBSMedium duty
TYPE-III200 IBSLight duty

For further convenience, we have listed some often-used accessories weights. For a better assumption, let’s have a look.

Accessories ListApproximate Weight
Toolbox with toolset30-35 IBS
Ceiling fan25-30 IBS
Portable spray15-20 IBS
Sheet of plywood70-80 IBS
5 gallons of the paint bucket55-60 IBS

Note: This chart is only for different accessories weight assumptions, nothing more.

Frequently Asked Questions about ladder angle rule

  • Why do I need to follow the 4:1 ratio rule at the time of ladder height measurement?

Answer: Visibly, you want to know the ladder height calculation for choosing the ideal ladder height and safety climbing. Consequently, any extension or telescoping ladder can’t ensure safety unless you follow the 4:1 ratio rule at the time of ladder base placement.

It is as important as your height chart calculation, and you can’t deny it under any condition.

  • Is the 4:1 ratio rule difficult to understand?

Answer: No, it is very easy to understand. For example, if you want to reach 12 feet height, you need to place your ladder 3 feet away from the supporting place.

Meaning, for every 4 feet, you need to place your ladder 1 foot away from the supporting wall.

  • What is the most unavoidable ladder safety rule?

Answer: Our mention, all safety rules are extensive, and you need to obey all the rules carefully. But in the case of priority, you must follow the 3 points of the contract rule. Two-foot and one hand or two hands one-foot connection every time you climb up on a ladder.

  • What is the cause of maximum ladder accidents?

Answer: There are a few reasons behind for fatal ladder accident. The most common causes are failing to place the ladder base following the right-angle rule, overloaded, overreach, and failure to measure ladder height according to working height.

  • How do I learn what size ladder I need?

Answer: Firstly, measure your working height and follow the above chart according to your ladder type. And then, you will learn what size ladder you need for your project.

Final words

That is all we have today. Hopefully, you have found our above discussion, technique, and chart of ladder height calculator helpful. We have provided all information regarding the ladder height chart. Besides, try to provide extra tips and guidance for better understanding.

Good luck with your ladder project, and hope for your safety while working.

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