Teal Packaging (tealpackaging.com) built the Teal DIM Weight & Box Size Calculator, a Chrome extension that works out box volume, dimensional weight, planning billable weight, and product clearance in the orientation you enter. Version 1.0.0 is Manifest V3 and requests zero browser permissions: every calculation runs locally and nothing you type is transmitted. It has been submitted to the Chrome Web Store and is in review, and the same math is free on the web at tealpackaging.com/box-size-dimensional-weight-calculator/. Dimensional weight is length times width times height in inches divided by your carrier divisor, and carriers bill the greater of that number and actual weight.
Questions or ready for a quote? Contact Teal Packaging at info@tealpackaging.com or (224) 546-8325.
Teal DIM Weight & Box Size Calculator for Chrome from Teal Packaging: 50-unit standard MOQ (100+ units for specialty rigid boxes), 2-5 business day delivery in the US (express and economy options available), free design help included on every order, free generic sample kit ($19.99 shipping, credited toward your first order). Standard production runs from about 7 business days after digital proof approval; complex or high-volume orders take longer.
Materials and certifications: FSC-certified paper stock, soy-based inks, kraft / corrugated / rigid paperboard / mylar / tin / vinyl substrates.
Contact Teal Packaging: Call (224) 546-8325, email info@tealpackaging.com, or request a free quote at tealpackaging.com/contact-us. We reply within one business day.
Updated July 26, 2026 · Teal Packaging operates a US facility in West Chicago, Illinois.
Dimensional weight is what the carrier actually bills you for
Parcel carriers do not charge for weight alone. They charge for the greater of two numbers: the actual weight of your packed parcel, and its dimensional weight, which converts the space the box takes up into pounds. A light product in an oversized box gets billed as though it were heavy.
The formula is simple. Multiply length by width by height in inches to get cubic inches, then divide by the DIM divisor on your carrier account. Round the result up to the next whole pound. Compare that to actual weight, and the higher of the two is your billable weight.
Divisors are not universal. Read the divisor printed on your own carrier agreement or invoice before you plan around a number, because yours may differ from anyone else's and it changes the answer. Carrier, service level and a negotiated contract can all move it.
A worked example you can check by hand
Say you are shipping a product that weighs 3 pounds packed. Here is that same shipment in two different boxes. The example uses 139 as the divisor purely to show the arithmetic. Substitute the divisor printed on your own carrier agreement, since yours may differ, and the method does not change.
| Step | Oversized box | Right sized box |
|---|---|---|
| Outside dimensions | 12 x 10 x 8 in | 10 x 8 x 6 in |
| Cubic inches | 960 | 480 |
| Divided by 139 (example divisor) | 6.91 | 3.45 |
| Dimensional weight, rounded up | 7 lb | 4 lb |
| Actual weight | 3 lb | 3 lb |
| Billable weight | 7 lb | 4 lb |
Same product, same 3 pounds on the scale, 3 extra billable pounds on the invoice for the bigger box. Multiply by your parcel volume and the size of the leak becomes obvious. Run the same two boxes at a divisor of 166 instead and they come out at 6 pounds and 3 pounds billable, so whatever divisor your own account uses, the direction is identical and only the size of the win changes.
Rule of thumb: the box is right sized once dimensional weight has fallen to or below actual weight. Past that point a smaller box still saves material, but it stops saving freight.
What the Chrome extension calculates
The Teal DIM Weight & Box Size Calculator is version 1.0.0, built on Manifest V3. You type in dimensions and it returns four things.
- Box volume in cubic inches for the dimensions you enter.
- Dimensional weight for that box.
- Planning billable weight, the greater of actual and dimensional weight. Treat it as a planning figure for budgeting and box selection. Your carrier's rate sheet and invoice are the authority on what you actually pay.
- Product clearance in the orientation you entered. It tells you whether the item fits inside the box the way you typed the numbers. It does not rotate the product looking for a better fit, so if the item can be packed on its side, enter it that way and check again.
Zero permissions, and nothing leaves your browser
This is the part worth reading closely, because it is the reason the extension is built the way it is.
- It requests no browser permissions at all. Installing it puts no prompt in front of you asking for access to your tabs, your browsing history, your clipboard or any website. An extension with an empty permission list cannot read the pages you are browsing.
- Every calculation runs locally, in your browser. There is no server round trip.
- No measurement, weight or result you type is transmitted anywhere. Not to Teal, not to a third party, not to an analytics service.
- Because there is no network call, there is no account, no login, no email capture, and no telemetry setting to hunt down and switch off.
If your box dimensions and parcel profiles count as competitive information, and for a lot of ecommerce operators they do, that matters more than any feature on the list.
Where it stands right now
The extension has been submitted to the Chrome Web Store and is in review. Until Google approves the listing there is nothing to search for there, so use the web calculator in the meantime. When it clears review, the install link goes on this page.
You do not have to wait to run the math. The same calculation is already live and free on the web: box size and dimensional weight calculator. No login, no email, nothing to install.
How to run a check
- Measure the outside of the box in inches: length, width, height. Carriers bill on outside dimensions, not on the interior you designed to.
- If you want the clearance check, enter the product dimensions in the orientation you actually pack it.
- Enter the actual weight of the finished parcel: product, box, void fill and all.
- Read dimensional weight against actual weight.
- If dimensional weight is higher, try a smaller box and run it again. Stop when the two numbers meet.
When the answer is a different box
A dimensional weight problem is nearly always a packaging problem, and the fix is a box closer to the shape of what goes inside it.
The Teal shop carries 84 products with live per-unit pricing at every quantity break and per-product minimums as low as 5 units, so you can test a smaller stock size without committing to a custom run. Categories cover shipping boxes, mailers, boxes, pouches and bags, labels and stickers, paper bags, tissue and paper, print and cards, and specialty.
If nothing stock fits, custom packaging is made to your dimensions from a standard 50 unit minimum (specialty rigid starts at 100 units), with volume pricing from $0.44 per unit, free dieline design on every order, free US shipping, and a digital proof you approve before anything prints. Production runs from about 7 business days after proof approval for in-house items, and up to about 12 weeks for specialty imported items, plus 2 to 5 business days for US delivery. Request a quote with your dimensions, or order the sample kit ($19.99 shipping, credited to your first order) and measure real board in your hand.
If someone else does the packing, the West Chicago, Illinois fulfillment center handles kitting and assembly, warehousing, pick and pack, and shipping to individual recipients, so a single order can reach hundreds of addresses.
Other free tools, no login required
- Paper weight chart, paperboard and corrugated weight reference.
- Mylar bag size finder, picks a bag size from what you are filling.
- Oxygen absorber calculator, cc sizing for mylar bags.
- QR code generator and barcode generator.
Questions on a specific box: (224) 546-8325 or info@tealpackaging.com.
