We built something small that we hope might be useful to others who ship packages.
At Baraka, we reuse cartons whenever possible. It's better for the planet, and honestly, it just makes sense.But reusing boxes means we're constantly trying to figure out which USPS cubic tier a particular carton fits into – and doing that math over and over gets old pretty fast.
So we made a simple calculator for ourselves. You enter your box dimensions in inches (length, width, and height), and it instantly tells you whether your package qualifies for USPS Ground Advantage Cubic pricing and which Priority Mail Cubic tier it falls into.
We figured if it's helpful to us, maybe it'll be helpful to someone else too.
What the calculator does
- Calculates cubic feet from your box dimensions
- Shows if your package qualifies for Ground Advantage Cubic (under 0.5 cubic feet)
- Identifies the correct Priority Mail Cubic tier (0.1 through 0.5)
- Works with any box dimensions – new boxes, reused boxes, whatever you've got
It's free to use, no sign-up required. You can find it in our website footer or go directly here:bit.ly/RRR-USPS.
To everyone in our community who saves and reuses boxes, who thinks twice before tossing packaging, who makes that small extra effort to reduce waste – thank you. These choices add up. Our collective environmental footprint gets a little lighter every time we choose to reuse instead of replace.
We're grateful to be part of a network of customers, partners, and fellow small businesses who care about these things.
If you find the calculator useful, we'd love to hear from you.
Frequently Asked Questions
How can I find the USPS tier size of a carton I want to reuse?
Measure the length, width, and height of your box in inches, then enter those dimensions into our free Cubic Tier Calculator. It will instantly tell you which USPS cubic tier your box qualifies for.
How do I calculate USPS cubic tier?
Multiply your box's length × width × height (in inches) to get cubic inches. Divide by 1,728 to get cubic feet. USPS assigns tiers in 0.1 increments from 0.1 to 1.0 cubic feet. Our calculator does all this math for you automatically.
What cubic tier is my package?
Enter your box dimensions into our free calculator to find out instantly. The calculator shows both your cubic tier and whether you qualify for Priority Mail Cubic or Ground Advantage Cubic pricing.
How do I find Priority Mail cubic tier from box dimensions?
Priority Mail Cubic pricing is available for tiers 0.1 through 0.5 (up to 864 cubic inches). Measure your box, enter the dimensions into our calculator, and it will tell you if your package qualifies for Priority Mail Cubic and which tier it falls into.
What is USPS Ground Advantage cubic pricing?
Ground Advantage Cubic is available for all tiers from 0.1 to 1.0 (up to 1,728 cubic inches). It's often more economical than weight-based pricing for dense, heavy items in small boxes. Maximum weight is 20 lbs and no single dimension can exceed 18 inches.
What size box for cubic tier 0.3?
Tier 0.3 covers packages up to 518 cubic inches. Example box sizes that fit tier 0.3: 10" × 8" × 6" (480 cu in), 9" × 9" × 6" (486 cu in), or 12" × 7" × 6" (504 cu in). Use our calculator to check any box dimensions.
Is there a free USPS shipping tier calculator?
Yes! We built a free calculator at bit.ly/RRR-USPS – no sign-up required. It calculates both Ground Advantage and Priority Mail cubic tiers from any box dimensions.
Scan to Open
Point your phone’s camera at this QR code to open the calculator instantly.
