DIM weight formula
Multiply length x width x height, then divide by the carrier divisor. Common US planning divisors are 139, 166, and sometimes 194 depending on the service level and account.
Shipping size planner
Box Size and Dimensional Weight Calculator
Calculate box volume, dimensional weight, billable shipping weight, and product clearance before you quote custom mailer boxes, shipping boxes, subscription boxes, or ecommerce packaging. If DIM weight is higher than actual weight, a smaller carton or insert-ready mailer can reduce avoidable freight cost.
Free to use, no login, nothing you type leaves your browser.
50-unit minimum
Free dieline and proof
Free US shipping
50unit minimum
~7 bdfrom proof
Freedesign + shipping
USprint + fulfillment
Also a Chrome extension. Install the Teal DIM Weight and Box Size Calculator: zero permissions, runs locally, nothing leaves your browser.
Key Takeaway
The Box Size and Dimensional Weight Calculator from Teal Packaging estimates box volume, DIM weight, and billable shipping weight before you commit to a carton size. Enter length, width, and height in inches, pick a carrier divisor (139, 166, or 194), and compare the result against actual weight, since carriers usually bill the higher number. Teal Packaging, a US-based packaging supplier, produces right-sized custom mailer and shipping boxes from a 50-unit minimum with volume pricing from $0.44 per unit, free dieline design, and free US shipping. Ecommerce brands, subscription services, and fulfillment teams use it to cut avoidable freight cost.
Questions or ready for a quote? Contact Teal Packaging at info@tealpackaging.com or (224) 546-8325.
Use the Result Before You Finalize a Box Size
Carriers compare actual weight against dimensional weight, then usually bill the higher number. A box that looks only slightly oversized can still push an ecommerce order into a higher billable weight.
What to send Teal
Send product dimensions, product weight, target box style, clearance needs, insert requirements, order quantity, and the ship-to destination or fulfillment lane.
When to resize
Resize when DIM weight is higher than actual weight, when void fill is doing too much work, or when the product can move enough to scuff, break, or create a poor unboxing experience.
Then quote the exact box
Your numbers carry straight into the quote. A free dieline and a digital proof come back before anything prints, from a 50-unit minimum.
Right-size the box
Reducing unused internal space can lower billable shipping weight, material use, and void fill without weakening the package.
Plan around inserts
Paperboard, corrugated, foam, or molded pulp inserts change the internal fit and should be included before final box dimensions are approved.
Quote the structure
Use the calculated dimensions to quote mailer boxes, corrugated shipping boxes, folding cartons, subscription boxes, or ecommerce packaging.
Quote this spec
Your result is already filled in below. Add quantity and where to send the proof.
Questions buyers ask
What is dimensional weight?
Dimensional weight estimates shipping weight from package size. Carriers compare it with actual weight and usually bill the higher number.
How do I calculate dimensional weight for a box?
Multiply length by width by height to get cubic inches, then divide by the carrier divisor. For example, a 12 x 9 x 4 inch box has 432 cubic inches. With a 139 divisor, DIM weight is about 3.1 lb.
Which dimensional divisor should I use?
Many US parcel calculations use 139 for retail-style rates and 166 for some negotiated or economy lanes. Always confirm with your carrier.
How much clearance should I add around a product?
Start with 0.25 to 0.5 inches per side for small products, then increase for fragile items, inserts, or protective void fill.
What box size should I use for ecommerce shipping?
Use the smallest box that still protects the product, leaves room for inserts or cushioning, and does not crush corners. For fragile products, protection should take priority over the absolute smallest outer size.
Can Teal help right-size custom mailer boxes?
Yes. Send product dimensions, weight, quantity, artwork, insert needs, and shipping constraints through the quote form so Teal can review a right-sized mailer or shipping box.
