How to Become an Interior Designer: Understanding Scale

Updated 2025.

Key Points

Introduction

If you’re reading this article, it’s likely because you’ve at least played with the idea of a career as an interior designer. To get started, the first logical step is to get some professional training under your belt. After all, an eye for design is great – but it can only get you so far. If you want to know how to be an interior designer and truly succeed, you’ll need the technical skills to turn your ideas into actual design plans.

In particular, one of the key skills you’ll need to have is the ability to draw to scale. After all, you can’t create a functional design without drawing a floorplan that accurately represents your client’s space. But if it’s been a while since your last math class, drawing to scale can seem complicated.

Not to worry, though! In this post, we’ll de-mystify the concept of scale.

So, keep reading to discover what scale is, how to draw it, and learn how to become an interior designer!

How to Become an Interior Designer: Understanding Scale Drawing

A scale drawing shows an accurate representation of a real-life space – but with smaller, proportional measurements. Creating plans to scale is an essential and practical design industry standard. But why is this?

Designers use scale because you can’t realistically draw life-sized floorplans. This would take far too long and be far too complicated! When you draw a floorplan to scale, however, you can instead create a visual representation of the real-life room.

To create a scale drawing, you’ll need to take real-life measurements and reduce them using a uniform ratio. This way, they fit on the page. The cool part is that if you took a scale drawing and blew it up to real-life size, all the proportions would be accurate. The design would fit in the real room, like a hand in a glove!

Moreover, scale drawing also helps you design a room without having to be in the physical room itself. For example, imagine that you’re trying to place furniture to your client’s room design. Designing to scale will give you accurate idea of how the pieces will work together and fit in the space, even if you’re not currently in that space.

What Are Scale Ratios?

The One-Inch Scale

When we say a drawing is “to scale,” what we mean is that one unit of measurement on the paper equals one unit of measurement in real life.

For example: 1 inch on paper can represent 1 foot in real life. This would be called one-inch (1”) scale. One-inch scale is also sometimes represented as a ratio. This ratio is written as “1:12”, because 1 inch on paper = 1 foot (or 12 inches) in real life.

Let’s say, for instance, that a dining table is drawn using a one-inch scale. On the page, the table top measures 3 inches wide by 4 inches long. Because 1 inch on the page represents 1 foot in real life, you know that this table top will be 3 feet wide by 4 feet long, in real life, when placed in your client’s actual room.

The Quarter-Inch Scale

Although a one-inch scale is the easiest to work with, it often makes floorplans that are too big to be useful. A one-inch scale drawing of a room might still be too big to fit on a page.

For this reason, interior designers typically use a quarter-inch scale to create scaled drawings. In this case, 1/4 inches on paper represents one foot in real life.

With that in mind, let’s reconsider that same dining table, starting with the width. Remember, the table is 3 feet wide in real life. Since 1/4 inches on the page represents 1 foot in real life, you’ll need to multiply 1/4 inches by 3 in order to determine the scaled measurement on the page.

1/4 inches multiplied by 3 = 3/4 inches. So, on paper, the dining table will be 3/4 inches wide.

Next, let’s find the length of the dining table using this same quarter-inch scale. The table is 4 feet long in real life. So, we’ll need to multiply 1/4 inches by 4, which equals 1 inch. Therefore, on paper, the dining table will be 1 inch long.

Therefore, when drawing the dining room table into your floorplan, it would be 3/4 inches wide by 1 inch long.

We Get It, Math Can Be Confusing…

Not everyone comprehends mathematics as easily as others. If you’re someone who struggles with calculations (we feel you), perhaps the above sounds a bit confusing. However, once you grasp the core concepts, you’ll find that the math is actually quite simple!

There are two helpful tricks that can make your life easier. These tricks will help you figure out real-life measurements when looking at a scale drawing – or, on the flip side, figure out scaled-down measurements based on real-life.

Understanding Scale: 2 Tricks to Remember

How To Become an Interior Designer: Knowing The Architect’s Scale

We’re sure you’ve heard the phrase, “The right tool for the job”. As an interior designer, the right tool for YOU is an architect’s scale.

An architect’s scale is a six-sided ruler that provides measurements for twelve different scales. On a standard 12-inch ruler, each side uses a single unit of measurement, which you then use to measure from left to right.

The architect’s scale is different. Here, you can measure from left to right OR right to left, depending on which side of the ruler you’re using. For instance, the 1/8-inch measurement on an architect’s scale starts at the left edge of the ruler. The 1/4-inch scale, however, begins on the right side of the ruler, and is read right to left.

Another difference is that a standard ruler measures in inches and centimeters. But an architect’s scale provides the scale measurements typically used in design:

Why You’ll Like The Architect’s Scale

Perhaps you want to know how to become an interior designer and make this your full-time career, but you aren’t so crazy about the mathematical side of things. Well, you’ll be thrilled to know that an architect’s scale can take some of that pressure off you.

The architect’s scale actually reduces the amount of math you’d otherwise need to put into a scale drawing, because the markings on each side of it have already converted “real-life measurements” into a scale. This way, you can use them when you draw your design floorplans.

For example, take a look at your own architect’s scale. Now turn to the side labelled “1/4.” This side of the ruler allows you to draw scaled floorplans using a quarter-inch scale. Each full increment on that side of the ruler is actually 1/4 inches long, but represents one foot in real life.

You might find it difficult to use the architect’s scale at first – but that’s okay! Becoming an interior designer doesn’t happen overnight, and neither does mastering all of the complicated concepts. The key is to not be intimidated by this tool. In reality, it looks more complicated than it actually is.

Once you’ve mastered it, you’ll wonder why you didn’t learn about it sooner. The best way to get comfortable with an architect’s scale is to actually use it. So, start practicing. After all, practice makes perfect!

Conclusion

Don’t let the technical side of design discourage you from pursuing your dream of becoming an interior designer! Yes, understanding scale and making technical drawings are difficult parts of learning design. But the more you practice, the easier everything will be.

So, practice drawing scaled floorplans of the rooms in your own home. This will help you get more comfortable with the process. Before long, you’ll be using this skill to turn floorplans into fully-realized designs – and transform real rooms for real clients!

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