The "No Math" Guide to Building Drawers (That Actually Fit)

Let’s be honest: for most DIYers, the scariest part of building a dresser or cabinet isn't the frame, it’s the drawers.

If you’ve ever built a drawer that turned out 1/8th of an inch too wide to slide in, or one that fell off the tracks because it was too narrow, you know the pain. Conventional woodworking tells you to measure the opening, do a bunch of fractional math to account for slide clearance, and hope you cut perfectly.

I don't do that.

I use a reverse engineering method that requires zero math and guarantees perfect results every single time. Here is the beginner's guide to building bulletproof drawers.

What You Need

• Material: 1/2" or 3/4" Plywood (for the box sides) & 1/4" Plywood (for the bottom).

• Hardware: Side mount ball bearing drawer slides. (I like using soft close)

• Tools: Table saw (or circular saw), Drill, Pocket Hole Jig.

• The Secret Weapon: Scrap wood spacers.

Step 1: Install the Slides First

Most people build the box first, then struggle to install the slides to match the box. Do the opposite.

1. Cut two pieces of scrap wood to the exact height you want your drawer to sit off the bottom (e.g., 2 inches).

2. Place these spacers inside your cabinet.

3. Rest your drawer slide on top of the spacer and screw it into the cabinet wall.

4. Repeat for the other side.

Why this works: Gravity does the work for you. Your slides are now perfectly level and perfectly aligned with each other, and you didn't even pick up a tape measure.

Installing drawer slides

Step 2: The "Golden Measurement"

Now that the slides are installed in the cabinet, install the drawer sides to the slides. The sides are usually the same length as the sides. Now you can find the exact width your drawer box needs to be.

Take your tape measure and measure the distance from the inside of the left drawer side to the inside of the right side.

• Don't add anything.

• Don't subtract anything.

• Don't do math.

Whatever that number is on the tape measure... that is exactly how wide you cut your drawer box front and back.

Measuring between drawer sides

Step 3: The Bottom (Don't Skip This!)

You need a floor for your drawer. You have two options:

• The "Pro" Way (Dado/Groove): Before assembling, use your table saw to cut a groove 1/4" up from the bottom of all your pieces. Slide the 1/4" plywood floor into the groove, then screw the box together. This traps the bottom in so it can never fall out.

• The "Easy" Way: Just cut a piece of 1/4" plywood to the exact dimensions of your assembled box and glue/nail it to the bottom

1/4" groove fort he bottom of drawer box

Step 4: Build the Box

Now we just need to assemble the box to that width.

The Cut List

• Front & Back: Cut these to the "Golden Measurement" length you just found.

  
  

The Joinery

For beginners, Pocket Holes are the best friend of drawer construction.

1. Drill pocket holes on the outside faces of your Front and Back pieces.

2. Glue and screw the Front first, and if you used a groove for the bottom, slide that bottom in, then finish by screwing on the back pieces between the Side pieces.

Tip: Make sure your pocket holes are on the outside (front and back) because the Drawer Face will cover the front ones, and nobody looks at the back ones!

Screwing together the front of the drawer box

Sliding in the 1/4" groove of the drawer box

Screwing together the back piece of the drawer box

Step 5: The "Click"

Put the drawer box onto the slides.

Since you measured the gap between the slides to get your box width, when you go to insert the drawer, it should slide in with a satisfying click. No binding, no gaps.

Fitting the drawer box into the cabinet

Final Thoughts

Building drawers doesn't have to be a math test. By using spacers and measuring the gap after the slides and sides are installed, you eliminate the variables that usually cause errors.

Give this method a shot on your next build, your sanity will thank you!