Dimensional Weight Calculator
Estimate dimensional weight from package dimensions and a carrier-supplied divisor.
Parcel packing and measurement
Measure the parcel, protect the item, then check the current carrier rule.
Calculate dimensional weight, length plus girth, and box fill while keeping USPS, carrier, hazardous-material, customs, and current price rules separate.
Interactive planning
Free tools that show the method
Enter your own numbers, see the estimate, then read the assumptions before acting.
Length Plus Girth Calculator
Calculate the longest side plus twice the other two dimensions.
Box-to-Item Volume Worksheet
Compare item dimensions with inside-box dimensions in the entered orientation, then review rectangular volume before planning cushioning.
Topic library
Start with the part you need
Focused sections keep each guide close to a real task instead of collecting unrelated advice.
Boxes & MeasuringBox choice, reuse checks, dimensions, weight, fit, mailer types, and organized supplies.
Packing MethodsUSPS-grounded cushioning, stabilization, separation, common-item packing, and inside-address practices.
Labels & AddressingDomestic and international address preparation, label placement, barcode care, and customs-form orientation.
Services, Cost & TrackingComparable quotes, postal service features, postage inputs, tracking, insurance, signatures, and deadlines.
Restrictions, Returns & ProblemsMailability research, HAZMAT routing, returns, claims, address mistakes, and delivery scams.
Editorial guides
Latest practical articles
Each article includes a concrete workflow, a worked example, a checklist, limitations, and source links.
Restrictions, Returns & Problems
Can I Mail This? A Safe Research Path for Restricted Items
A practical restrictions, returns & problems guide to can i mail this? a safe research path for restricted items, with a repeatable method, worked example, checklist, limitations, and official source links.
Restrictions, Returns & Problems
Shipping Lithium Batteries: Why the Exact Scenario Matters
A practical restrictions, returns & problems guide to shipping lithium batteries — why the exact scenario matters, with a repeatable method, worked example, checklist, limitations, and official source links.
Services, Cost & Tracking
How to Compare USPS Package Services on Price, Speed, and Features
A practical services, cost & tracking guide to compare usps package services on price, speed, and features, with a repeatable method, worked example, checklist, limitations, and official source links.
Services, Cost & Tracking
Flat Rate Box vs. Your Own Box: How to Compare Current Quotes
A practical services, cost & tracking guide to flat rate box vs. your own box — how to compare current quotes, with a repeatable method, worked example, checklist, limitations, and official source links.
Labels & Addressing
How to Format a US Domestic Package Address
A practical labels & addressing guide to format a us domestic package address, with a repeatable method, worked example, checklist, limitations, and official source links.
Labels & Addressing
Where to Put an Apartment or Unit Number in a Shipping Address
A practical labels & addressing guide to where to put an apartment or unit number in a shipping address, with a repeatable method, worked example, checklist, limitations, and official source links.
Packing Methods
Cushioning Materials Explained: Fill, Wrap, and Separation
A practical packing methods guide to cushioning materials understood — fill, wrap, and separation, with a repeatable method, worked example, checklist, limitations, and official source links.
Packing Methods
How to Pack a Box Using the USPS Package Preparation Steps
A practical packing methods guide to pack a box using the usps package preparation steps, with a repeatable method, worked example, checklist, limitations, and official source links.
Boxes & Measuring
How to Choose the Right Shipping Box for an Item
A practical boxes & measuring guide to choose the right shipping box for an item, with a repeatable method, worked example, checklist, limitations, and official source links.
How we work
Useful before optimized
We show measurement math, cite USPS and federal rules where applicable, and require the chosen carrier’s current acceptance and checkout result to control.
See sources and methodologyImportant limitations
Tools provide planning estimates, not professional, medical, legal, safety, carrier, park, or manufacturer determinations. Always verify time-sensitive details with the linked official source.