How to Measure For Drawer Slides in 7 Easy Steps

Measure twice, order once 

When it’s time to order new drawer slides, measuring can feel confusing. Manufacturer diagrams have a lot of numbers, tables for deductions, and arrows that seem to go every which way. Figuring out how to measure for drawer slides can be tricky, but with a tape measure and a look at your cabinet and drawer, it quickly makes sense.

We’ll walk you through the steps so you can measure cabinet drawer slides before installation with confidence.

In this article:

• Tools and Supplies You’ll Need
• Step-by-Step Instructions: How to Measure for Drawer Slides
• Choosing the Right Slide Based on Measurements
• Pro Tips for a Smooth Installation
• Common Mistakes to Avoid
• Eagle Woodworking Offers Drawers and Drawer Slides to Fit Your Needs
• Frequently asked questions

Tools and Supplies You’ll Need 

You won’t need a lot of tools, but make sure to have the following handy:

• Tape measure
• Notepad or scrap paper
• Pencil 

Step-by-Step Instructions: How to Measure for Drawer Slides 

Manufacturers have slightly different drawer slide designs, but measuring for the slides will be very similar regardless of what you choose. Note that these instructions are for replacing drawer slides. If you’re installing drawers in a space for the first time, skip to step 5.

Step 1: Remove the Drawer and Slides 

How you remove the drawer depends on the type of drawer slides you have: 

• Roller drawer slides: Pull the drawer out and lift up slightly to remove the roller from the track. Roller drawer slides might also have safety tabs that you’ll need to release before pulling the drawer out of the cabinet.
• Side-mount slides: Pull the drawer out and find the levers on the track on each side of the drawer. Push the levers up or down to remove the drawer
• Undermount slides: Pull the drawer out and find the clips on the bottom front corners of the drawer. Release the clips to remove the drawer. 

Remove the drawer slides from the drawer and from inside the cabinet, and set them aside.

Step 2: Measure Drawer Depth 

Measure from the front of the drawer box to the back of the drawer box, using the outside dimensions of the drawer box, not inside. You’ll use this measurement to determine the drawer slide length. Don’t include the drawer front.

• Undermount drawer slides: Come in increments of 3” and need to be the exact length of the drawer box.
• Side-mount and center-mount slides: Come in 2” increments. Round down to account for clearance at the back of the cabinet.

Step 3: Measure Drawer Box Width and Height 

Width and height measurements are needed if you’re measuring for dovetail drawers or building your own drawers. There should be enough clearance on each side and at the top so the drawer can slide smoothly. Refer to the table in step 5 for clearance. 

Step 4: Measure Drawer Box Thickness

The drawer box thickness is the thickness of the drawer material. You need to know this measurement before you install undermount drawer slides. Undermount slides will be specified for up to ¾” or up to ⅝” thick material, which provides enough clearance on each side for the drawer to slide in and out. 

Step 5: Measure Cabinet Opening 

Measuring the cabinet opening is especially important if you're building your own drawers or changing the slide style because you need to account for clearance. If you’re replacing existing drawer slides and will be using the exact same drawer size and slide configuration as before, this is less important because the drawers should already have the right amount of clearance. 

Step 6: Account for Slide Type and Setback 

Here’s a recap of how to measure for each slide type.

• Side-mount: The side-mount slide measurement will correspond to the drawer length measurement, but should be rounded down to the nearest whole and even number. So a 22.5” drawer would need a 22” side-mount slide. Side-mount slides usually need up to 3/8 inch of clearance between the drawer and back of the cabinet.
• Undermount: The undermount drawer slide measurement will correspond to the drawer length measurement. The slide will actually be a bit longer to leave room for the pin in the back, but choose the one that matches the drawer length. Undermount slides come in 3” increments. Undermount slides may require a bit more clearance between the drawer and the back of the cabinet, often around 1/2 inch to account for the mechanism’s rear stop feature.
• Centermount: Measure from the front of the drawer box to the back of the drawer box. Centermount drawer slides come in 2” increments.

Drawer slides for frameless cabinets have a setback measurement, which means how far back the slide is installed from the front of the cabinet box. Always check the manufacturer’s instructions for the appropriate setback based on the style and manufacturer.

Step 7: Determine Slide Length 

Standard drawer slide length ranges from 9” to 30”. Standard kitchen cabinets typically use 21” undermount slides and 22” side-mount slides. However, custom cabinetry will often have a wider range of depths utilized throughout the kitchen. Undermount slides can go from 9” to 30”, while sidemounts can range from 10” to 30”. Even though 21” depth is the most common depth, you should always measure your drawer boxes to make sure you have the appropriate size when replacing drawer slides. Always round your measurement down, so the drawer can slide smoothly without getting hung up on the cabinet. 

For undermount slides, you’ll also need to choose the type of clip you want. Undermount slide clips are typically adjustable with some allowing for 2-way, 4-way, or 6-way adjustments. The more adjustable they are, the more flexibility they’ll offer for drawer adjustments. You can also choose from heavy-duty and narrow clips, so you get the right amount of support or space for your drawers.  

Choosing the Right Slide Based on Measurements 

Choosing drawer slides can be as easy as determining the type of slide you currently have. If you’re replacing your existing slides, then you can go with the same type for easy replacement. If you want to switch the type of slide, then that’s where you’ll need to check for clearance to confirm everything will fit. 

Common Mistakes to Avoid 

Here are a few common mistakes to avoid when you measure for and install drawer slides:

• Wrong length: When it comes to ordering drawer slide length, the old adage “measure twice, cut once” can be adapted to “measure twice, order once.”
• Poor clearance: If the drawer slide is too long, there won’t be enough room for the drawer to close all the way. 
• Slides aren’t level: To work correctly, slides have to be level. If the drawer is binding, the slides may be tilted one way or the other. For side-mount slides, you can remove and level them before securing them onto the drawer again. Undermount drawer clips allow you to adjust the drawer, so leveling it may just be a matter of raising, lowering, or tilting the drawer into the correct position. When in doubt, order 6-way clips to provide maximum adjustability post-install.

Eagle Woodworking Offers Drawers and Drawer Slides to Fit Your Needs 

Measuring for drawer slides can seem intimidating, but when you actually get started, it’s easier than it seems. When you’re ready to order your cabinet drawer slides, Eagle Woodworking offers a variety of slides from respected manufacturers to keep your project on track and your drawers sliding smoothly.

Whether you’re a contractor, a cabinet maker, or a do-it-yourselfer, we can help you design and build your dream dovetail drawers. We work with a network of contractors to meet their needs for dovetail drawers and the necessary hardware to install them. Our premium craftsmanship, fast lead times, and AWI premium-grade quality products mean that you can be confident in our products and our service.

Now that you’ve measured your slides, read our article on how to install drawer slides for the next steps.

Frequently Asked Questions  

How do I know what size drawer slides I need? 

To find out what size drawer slides you need, measure the length of the drawer box to start. For undermount drawer slides, you’ll also need to know the drawer box side thickness, so you can buy the correct slides.  

What is the standard clearance needed for side-mount slides? 

Standard clearance for side-mount slides is ¼” on each side for ½” total clearance. 

How much space should I leave for drawer slides? 

The amount of space you need to leave for drawer slides depends on the type of drawer slide you’re using. Side-mount slides need at least ½” of clearance (¼” on each side). Undermount slides need less side clearance and the amount depends on the side thickness. Drawers that have a ½” thickness need ⅝” width clearance, and drawers that have a ⅝” thickness need ⅜”  width clearance. Undermount drawer slides need at least ¼” clearance at the top of the drawer. 

Should drawer slides be longer or shorter than the drawer? 

The drawer member of a drawer slide should be the same length as the drawer. The cabinet member will be slightly longer. 

Are soft-close slides measured differently? 

No, soft-close slides are measured the same way as standard-close slides. 

What size drawer slides do I need for a 24-inch cabinet? 

Even if you know the depth of your cabinet, you still need to measure the depth of your drawers because the clearance between the drawer and cabinet can vary. For a 24” cabinet with 1” of clearance in the back, you would need a 22” side-mount slide and a 21” undermount slide.