Shipping calculators
Measure the packed parcel, check the service limits, then apply the price and delivery window from your quote. These are separate decisions; a lower dimensional weight does not itself prove a cheaper shipment.
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Weight & dimensions
Shipping cost
Delivery times
Start with the parcel, then price the service
The combined weight worksheet compares scale and dimensional weight and lets you test a smaller carton. Its presets identify the billing system being modelled. Use the size checker to calculate length plus girth and compare recorded service limits. Passing a size limit does not establish eligibility for hazardous goods, a particular destination or a negotiated price.
A threshold can change the decision
Under the USPS dimensional rule, a rectangular 12 × 12 × 12 inch parcel is exactly one cubic foot and does not incur dimensional weight. A measured 12.1 × 12 × 12 inch parcel rounds to 13 × 12 × 12 inches before testing the threshold. Its dimensional weight is 1,872 ÷ 139, rounded up to 14 lb. Compare that with actual weight. Measure bulges and packaging, not just the product. See USPS DMM 113.
Use the price you can actually buy
The cost worksheet contains dated USPS tables and a mode for your own quoted rate. The sample rate and fuel percentage are examples. Other carriers also publish rate guides; we have not integrated them as live quotations. Enter accessorial charges and check whether the quote is per parcel or per shipment. Published postage estimates are not label purchases.
The delivery planner converts a quoted business-day range into dates after handling and cut-off assumptions. It does not track a parcel or predict a customs release. The elapsed-time calculator answers the different question of how many working days passed between two dates.
Can I compare international and US carrier rules?
The weight worksheet accepts metric and imperial measurements but calculates in each preset’s specified billing units. Local tariffs and account contracts can differ; use the linked source and your service agreement.
Does a smaller box always lower postage?
No. The parcel must cross a billed weight band or remove an applicable surcharge. A dense parcel may continue to bill on actual weight after the box shrinks.
The rest of the chain
A shipment is priced in stages, and the stage you are on is rarely the only one that costs you money.