Drawer Box Size Calculator

Build snug drawers for potting benches and sheds. No guesswork, just clear measurements every time. Print a cut list, then start assembling confidently now.

Enter your drawer details

Opening
Required
Enter a positive width.
Enter a positive height.
Measure from inside front to back stop.
Enter a positive depth.
Clearances
Use your slide/runner requirement.
Top + bottom combined clearance.
Space behind the drawer box.

Side height
Only used when Custom is selected.
Materials & joinery
How far the bottom sits into grooves.
Does not change size; helps planning.

Used only for Rabbet/Dado joinery.
Rounding affects displayed cut sizes.
Adds extra area for defects and trimming.
Cost uses area with waste.
Reset

Example data table

Sample inputs and outputs for quick reference. Always confirm hardware requirements.

Opening (W×H×D) Side clr Vert clr Back clr Thickness Outside (W×H×D)
18 × 6 × 20 in 0.5 in 0.25 in 1 in 0.5 in 17 × 5.75 × 19 in
450 × 150 × 500 mm 12 mm 6 mm 20 mm 12 mm 426 × 144 × 480 mm

Formula used

  • Outside width = Opening width − 2 × Side clearance.
  • Outside height = Opening height − Total vertical clearance.
  • Outside depth = Usable depth − Back clearance.
  • Inside width = Outside width − 2 × Material thickness.
  • Front/Back length = Inside width (add 2 × Rabbet depth if using Rabbet/Dado).
  • Inside depth = Outside depth − 2 × Material thickness.
  • Bottom panel = (Inside width + 2 × Groove depth) × (Inside depth + 2 × Groove depth).
  • Panel area sums sides, front/back, and bottom, then applies waste %.

How to use this calculator

  1. Measure the inside opening width, height, and usable depth.
  2. Enter the required side, vertical, and back clearances.
  3. Set your material thickness and bottom panel details.
  4. Choose joinery. Add rabbet/dado depth when applicable.
  5. Select rounding to match your measuring tools and workflow.
  6. Press Calculate and use the cut list to mark panels.
  7. Download CSV for a cut sheet or PDF for the shop.

Precision fit for garden storage drawers

Drawer boxes used in potting benches, seed cabinets, and shed organizers benefit from repeatable sizing. This calculator converts an opening into outside dimensions by subtracting slide and vertical clearances. By standardizing measurements, you reduce rework, protect tools, and keep supplies accessible during seasonal tasks. Documenting one successful drawer makes matching replacements simple.

Choosing clearances for runners and wood movement

Side clearance depends on the hardware system and the expected environment. Outdoor-adjacent garden spaces can swing in humidity, so allow room for seasonal movement and debris. Enter clearance per side, plus total top and bottom clearance, to prevent binding while maintaining a stable, square reveal. When in doubt, test one drawer and lock in the clearance as a shop standard.

Material thickness and joinery impact

Thickness drives the inside cavity and the length of the front and back panels. Butt construction sets front and back to the inside width. Rabbet or dado joinery increases panel length by the selected capture depth, improving glue surface and alignment. Keep joinery depth within the side thickness for strength. Consistent thickness selection also simplifies purchasing and reduces layout errors on sheet goods.

Bottom panel capture and moisture resilience

Garden drawers often store soil additives, fasteners, or watering parts, so a captured bottom helps resist racking. The calculator sizes the bottom using inside dimensions plus groove depth on each side. Pair this with a durable panel and appropriate sealing to limit swelling and extend service life. If loads are heavy, consider a thicker bottom or a center support to reduce sag.

Using exports for consistent workshop workflow

After calculating, the cut list is formatted for quick transfer to marking and cutting stations. CSV supports batch planning and material optimization, while the PDF is convenient at the bench. Apply a waste factor to account for kerf, defects, and test cuts. Consistent documentation improves repeatability across builds. Store your export files with project photos so you can replicate drawer sets years later.

FAQs

1) What opening size should I measure?

Measure the clear inside width and height where the drawer box will fit, plus the usable depth to the back stop. Avoid face-frame overhangs and trim that do not affect the box cavity.

2) How do I choose side clearance?

Use the requirement from your slides or runners. If you build simple wooden runners, include extra space for finish and seasonal swelling. Enter the clearance per side, not the total.

3) Why does joinery change front and back length?

Rabbet and dado styles seat the front and back into the sides. That capture adds length equal to twice the joinery depth, increasing glue area and helping keep the box aligned during assembly.

4) What groove depth should I use for the bottom?

Choose a groove depth that provides reliable capture without weakening the sides. A common approach is a shallow groove within the side thickness. The calculator limits groove depth to practical values.

5) Does bottom offset change the cut size?

No. Bottom offset is included as a planning note so you can position your groove or fasteners consistently. The bottom panel size is based on inside dimensions plus the groove capture.

6) How accurate are the rounding options?

Rounding adjusts displayed cut sizes to match common measuring tools. For final fabrication, verify with your hardware and test-fit scrap. Keep the calculator unrounded if you want full precision outputs.

Related Calculators

Kitchen remodel budget calculatorKitchen triangle distance calculatorCountertop seam plannerBacksplash grout calculatorCabinet count estimatorCabinet door size calculatorCabinet hardware quantity calculatorDrawer slide length calculatorShelf pin spacing plannerKitchen lighting layout calculator

Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.