How to measure drawer slides

Slides are crucial to the functionality and durability of your cabinet drawers. If they’re the wrong measurements, your drawers won’t fit properly, open and close smoothly, or handle the intended weight. 

Learning how to measure drawer slides involves more than just measuring the length and depth of your drawers. You must also understand the different types of slides and common mistakes to avoid. In this guide, we cover all these important areas so that you can keep your drawers gliding smoothly for years to come. 

Types of drawer slides

As the name suggests, a drawer slide is what allows your cabinet drawers to open and close properly. Also known as glides or runners, there are two main categories of drawer slides: 

• Roller slides use rollers to facilitate smooth movement. They are the most cost-effective and straightforward to install, making them popular for regular use.
• Ball-bearing slides use ball bearings for smooth and quiet operation and a drawer that fully extends. They outperform roller slides in terms of durability and load capacity.

Several varieties exist within these categories, each catering to specific needs and preferences:

• Side-mount slides use either rollers or ball bearings. They attach to the sides of the drawer and the cabinet. They are easy to install and the most common type. But because they require side clearance, they offer slightly less storage.
• Undermount slides are a type of ball-bearing slide, making them very strong. Mounted beneath both sides of the drawer, they’re hidden from view. Instead of side clearance, they need more vertical clearance, so they lose a bit of height.
• Center-mount slides typically use a roller mechanism. Unlike undermount slides, they consist of one runner that goes under the middle of the drawer. They are best suited for lightweight drawers on smaller cabinets.
• Soft-close slides have a mechanism that works on roller or ball-bearing slides. This mechanism slows down the closing action, preventing slamming and damage.

Understanding how to measure a drawer slide requires you to know the differences between these types so that you measure the correct dimensions. 

For example, if you don’t know how to measure undermount drawer slides, you might overlook the vertical clearance between the drawer bottom and the cabinet floor. This is crucial for undermount drawer slides but not for any other type. Missing this results in inadequate clearance, causing the drawer to scrape or bind against the cabinet. 

Tools needed to accurately measure drawer slides

Measuring drawer slides accurately requires some essential tools:

• • Measuring tape for determining dimensions 
  • Square or ruler for ensuring precise and straight measurements
  • Pencil for marking points on the drawer and cabinet, aiding in accurate alignment 
  • Notepad for writing the measurements down so you don’t forget 
  • Level for ensuring you install the drawer slides evenly and horizontally
  • Screwdriver for removing the drawer if necessary

Step-by-step guide to measuring drawer slides

Whether you want to know how to measure drawer slides for a brand-new cabinet renovation or how to measure drawer slides for replacement drawers, the process is fairly simple.

The rundown is that you need to measure the drawer’s length and depth to identify how long your slides need to be. You also need to subtract the drawer’s width from the cabinet’s opening width to determine if you can use side-mounted slides and, if so, how thick they need to be. 

But there are a couple of things to be aware of when measuring for drawer slides. Here’s a closer look at the process. 

Identify the type of drawer slide

Begin by removing your drawer from the cabinet. Now, you can examine the mounting location of the slides. For example:

• Side-mount slides are typically fixed on the sides.
• Undermount slides go beneath the drawer on both sides.
• Center-mount slides are at the center under the drawer.

If the slides have visible wheels, they are roller slides. If they have small, cylindrical components inside a carriage mechanism, they use ball bearings. If you’re unsure what type of slides they are, consult your product documentation.

If you’re working with brand-new cabinets that haven’t had runners installed yet, then you need to decide what type of slides your drawer’s dimensions can accommodate. For example, if there is insufficient space between the outer edge of your drawer and the inner edge of your cabinet, you shouldn’t use side-mounted slides. Instead, consider center-mount or undermount slides. 

Measure the drawer length

Using a measuring tape, place one end at the back of the drawer box and extend it along the bottom edge to the front of the drawer box. This is easier if you remove your drawer and place it on a flat surface.

It’s important to round down to the nearest whole number since drawer slides usually come in regular lengths. For example, if your drawer box measures 20.5 inches, look for 20-inch slides. However, if you’re learning how to measure for undermount drawer slides, don’t round down because undermount slides need to be the exact same length as the drawer. 

Remember: Measure the box, not the drawer front. The purpose of a front face is to stop the drawer from going into the cabinet. If you include it in your measurement, the drawer slide will stick out, or the drawer front will sit inside the cabinet frame. 

Measure drawer depth

The depth or height of your drawer (i.e., the distance between its highest and lowest point) is also important when understanding how to measure drawer slides. You use this measurement to ensure your slides provide adequate support and fit properly within the cabinet. 

If you’re installing undermount drawer slides, measuring the height of your drawer is doubly important, as they require more vertical clearance. Also measure from the floor of the cabinet to the bottom of the drawer — undermount runners need at least a half-inch of space here. 

If you don’t have sufficient height clearance, then choose side-mount slides, provided you have enough space on either side of the drawer. And that brings us to the next step.

Measuring drawer width and opening

Most drawer slides have a standardized width, so this measurement is less critical, especially if you’re just buying replacement slides. That said, it is important for determining the amount of clearance that new runners will provide if they’re side-mounted. The clearance is the space between the sides of the drawer and the interior walls of the cabinet.

You need to know the difference between your drawer’s width and the cabinet’s opening width to discern the amount of clearance you have. Here’s how to calculate it:

• For the width, measure from one side of the drawer to the other, placing the tape along the edge for precision.
• For the opening width, measure the distance between the inner edges of the cabinet where the drawer will slide in.
• For the clearance, subtract the drawer width from the opening width.

Selecting drawer slides with the right amount of clearance is vital for the smooth, unobstructed movement of your drawer within the cabinet. Calculating this will also help you figure out what type of slide will work with your drawer or cabinet.

Common mistakes to avoid when measuring drawer slides

It sounds simple enough, but sometimes the straightforwardness of measuring drawer dimensions leads to oversights. Here are some of the most common mistakes, their impact on the end result, and how to avoid them.

Inaccurately measuring the drawer length

Including the drawer’s front face, not removing the drawer before measuring, or misaligning the tape can all result in undersized or oversized slides. In turn, this affects the smooth operation of the drawer and compromises its functionality and longevity.

Only measuring one side of the drawer

Contrary to popular belief, drawers and cabinets aren’t necessarily equal on all sides. To minimize discrepancies and ensure your slides fit and function properly, you need to measure both sides of the drawer. Failing to do this can lead to lopsided drawers or unsightly gaps in your cabinetry. You can also expect operational issues, like tilting or stiff movement.

Not double-checking your measurements

Mistakes in measurements impact the fit, functionality, and aesthetics of your drawers and cabinets. To guarantee their accuracy, always double-check your numbers. As the saying goes, measure twice and cut — or install — once.  

Forgetting to consider clearance requirements

The type of slide you can install hinges on your side and height clearance. If you buy side-mount slides without calculating side clearance or undermount slides without calculating vertical clearance, your drawers might not fit. In general, drawer slides need about a half-inch of clearance on each side of a drawer, so make sure you check this before buying. 

Not considering the travel length

The travel length of a drawer slide refers to the maximum distance the slide can extend to when fully opened. Accounting for this is crucial for providing easy access to the drawer. If you don’t consider this, your drawers might not extend fully, limiting accessibility. To measure for travel length, pull your drawer all the way out and measure the distance from the back of the cabinet to the point where the drawer stops at its fully open position.

Overlooking slide compatibility

Installing the wrong type of drawer slide for a specific application or design can lead to functional issues and aesthetic mismatches. It’s crucial to ensure that the selected slides align with the intended use and design of your cabinets.

For example, while side-mount slides are cheaper and easier to install, undermount slides will serve you better if you have a large bottom drawer that needs to bear a lot of weight. Or, if you have the choice between side-mount and center-mount slides, the latter can help limit visual clutter.

And unless you’re replacing existing slides, never assume you know which type will fit your drawer — measure first and buy afterward. 

Stay up to date with The Cabinet Door Store

Figuring out how to measure drawer slides can be confusing if you’re not a seasoned professional. But by following the steps in this guide, you can do it confidently and effectively.

When you’re ready to choose your drawer slides, let The Cabinet Door Store give you the easiest shopping experience. Whether you need undermount or side-mount slides, we offer traditional and soft-close options. We have the hardware that will bring your project together.

If you’re planning an entire cabinet renovation, also check out our range of cabinet doors and matching drawer fronts and boxes, all of which come in various profiles, stains, and paints — everything you need to complete your project with quality and style.

To learn more about how we can support you, contact our expert team today.