Shipping Box Size Chart: Common Corrugated Dimensions and What Fits
Packaging Reference
A quick-reference guide to the most-used corrugated box sizes, from small cubes to moving cartons, with typical contents and edge-crush (ECT) notes. Dimensions are listed as length x width x height in inches.
Box sizes are always written L x W x H, measured as inside dimensions so your product actually fits.
Common corrugated box sizes and what fits
Grouped by shape and job. Use the smallest box that holds the item plus light cushioning, dimensions are inside measurements.
| Size (L x W x H) | Common name | Typical contents |
|---|---|---|
| Small cubes and singles | ||
| 6 x 6 x 6 | Small cube | Mugs, candles, small parts, jewelry boxes, cosmetics |
| 8 x 8 x 8 | Standard cube | Glassware, collectibles, mid-size fragile items with padding |
| 10 x 10 x 10 | Cube | Shoes, small appliances, bundled apparel, gift sets |
| 12 x 12 x 12 | Large cube | Bulk office supplies, small electronics, bundled goods |
| Flat and rectangular | ||
| 12 x 9 x 4 | Flat mailer box | Books, folded apparel, subscription kits, documents |
| 12 x 9 x 6 | Half-cube rectangle | Apparel, boxed retail products, subscription boxes |
| 14 x 10 x 6 | Flat rectangle | Framed prints, flat electronics, folded textiles |
| 12 x 8 x 6 | Small rectangle | Multi-item orders, kits, hardware, canned goods |
| Medium | ||
| 14 x 14 x 14 | Medium cube | Kitchenware, medium electronics, multi-pack orders |
| 16 x 12 x 12 | Medium rectangle | Small appliances, boxed sets, mid-weight bundles |
| 16 x 16 x 16 | X-large cube | Bulk retail, lampshades, lightweight bulky goods |
| 18 x 18 x 18 | Jumbo cube | Bulky low-weight goods, bedding sets, bundled soft goods |
| Moving and storage cartons | ||
| 18 x 18 x 24 | Medium moving box | General household moving, books in split loads, kitchen items |
| 20 x 20 x 20 | Large moving box | Linens, pillows, lampshades, bulky lightweight items |
| 24 x 18 x 24 | Large moving carton | Bulky low-density items, mixed household goods |
How to use this chart
Measure the complete item, including covers, protrusions and protective wrapping. Add the cushioning your product needs on both sides of each dimension. Compare that finished pack with the listed inside dimensions and check that the box closes without bulging. Measure the packed carton’s outside dimensions and weight when estimating delivery; inside dimensions describe fit, not the final shipping measurement.
Wide items · two depths
32 × 18 × 8 or 32 × 18 × 12: choose the depth your packed item needs
Both cartons have a 32 × 18 inch inside footprint. The taller option adds four inches of inside height; it does not add length or width. Measure the item with its protective packaging before choosing.
| Inside size | Choose when | Exact product |
|---|---|---|
| 32 × 18 × 8 | Your packed item fits the footprint and needs no more than eight inches of inside height. | View SKU 32188 · 15 boxes |
| 32 × 18 × 12 | The packed item fits the same footprint but needs more height. Check that the extra space works with your cushioning. | View SKU 321812 · 15 boxes |
Need 30 boxes?
Order two bundles of either product: 2 × 15 = 30 boxes. Three bundles contain 45 boxes. Compare the current merchandise subtotal and delivery estimate on the exact product page, then confirm the final total in the cart and checkout.
Shop boxes by exact size
Each size below has its own page with every in-stock construction (ECT grade, kraft or white, pack count) and live case pricing. Reordering from a Uline invoice instead? The Uline model cross-reference maps 752 S-numbers to the matching box size.
Cubes
6 x 6 x 6 · 8 x 8 x 8 · 9 x 9 x 9 · 10 x 10 x 10 · 12 x 12 x 12 · 14 x 14 x 14 · 16 x 16 x 16 · 18 x 18 x 18 · 20 x 20 x 20 · 24 x 24 x 24 · 12 x 12 x 18 · 12 x 12 x 24 · 18 x 18 x 24 · 6 x 6 x 36 · 25 x 25 x 25
Shallow, flat & rectangular
10 x 10 x 2 · 15 x 12 x 4 · 16 x 10 x 4 · 16 x 16 x 5 · 24 x 12 x 6 · 28 x 24 x 6 · 16 x 12 x 6 · 10 x 8 x 6 · 16 x 10 x 6 · 24 x 18 x 12 · 15 x 15 x 10 · 16 x 16 x 14 · 12 x 9 x 10 · 7 x 6 x 5 · 7 x 7 x 4 · 10 x 5 x 5 · 4 x 4 x 6 · 18 x 9 x 9 · 24 x 10 x 8
Long & tall
10 x 10 x 48 · 36 x 12 x 12 · 40 x 12 x 12 · 40 x 20 x 20 · 30 x 30 x 12 · 12 x 12 x 18 · 12 x 12 x 24 · 18 x 18 x 24 · 6 x 6 x 36
Corrugated mailers & tubes
8 x 7 x 4 mailers · 8 x 7 x 3 mailers · 13.5 x 3.5 x 3.5 mailers · 17.5 x 3.5 x 3.5 mailers · 5 x 60 tubes
Need the complete catalog view? The full directory of sizes by dimension lists every stocked footprint.
USPS Priority Mail flat rate box sizes
Flat rate boxes are a fixed-size, fixed-price system: these are the official USPS outside dimensions:
| Flat rate box | Outside dimensions |
|---|---|
| Small Flat Rate Box | 8 11/16" x 5 7/16" x 1 3/4" |
| Medium Flat Rate Box 1 (top-loading) | 11 1/4" x 8 3/4" x 6" |
| Medium Flat Rate Box 2 (side-loading) | 14" x 12" x 3 1/2" |
| Large Flat Rate Box | 12 1/4" x 12 1/4" x 6" |
| Large Board Game Box | 24 1/16" x 11 7/8" x 3 1/8" |
Inside dimensions run slightly smaller, and flat rate only wins for dense items headed far. The full breakdown, with inside dimensions, when flat rate beats your own box, and the crossover math, is in the USPS flat rate box size guide.
Box strength: ECT grades at a glance
Match both fit and construction to the shipment. ECT-32, ECT-44 and ECT-48 describe board ratings; the number alone does not specify wall construction or guarantee a contents-weight capacity. Check the exact product and its packaging requirements. Compare the ECT-32 size chart, the ECT-44 size chart, or the ECT vs 200 lb burst test guide if your spec sheet uses the older rating.
Frequently asked questions
What sizes are USPS Priority Mail flat rate boxes?
Are box sizes measured inside or outside?
What is the most common shipping box size?
What does L x W x H mean on a box?
How much extra space should I leave around a product?
Do I need a stronger box for a heavier item?
Find the right box
Match your dimensions to the collections below.
Shipping small, flat, or lightweight items instead? A bubble mailer or poly mailer may cost and weigh less than a box.