Sizes & Tools
Use size guides and calculators to reduce guesswork before buying boxes, mailers, labels, and scales.
Package size and supply-cost calculators
These tools are designed for early planning. They do not replace a carrier quote, service guide, or packaging test.
Dimensional Weight Calculator
Compare package volume with actual weight using an adjustable DIM divisor.
Length + Girth Calculator
Calculate girth and combined package length + girth in inches or centimetres.
Box Size Chooser
Add a protection allowance around a product and estimate a useful inside box size.
Mailer Size Chooser
Estimate usable mailer dimensions from a product’s length, width and thickness.
Monthly Shipping Supply Cost Estimator
Translate per-order packaging consumables into a monthly planning cost.
Measure the finished package
Carrier measurements generally apply to the parcel after it is packed. Product dimensions alone are not enough because cushioning, box walls, bulges and closures can change the outside size.
Keep size cost and supply cost separate
The cheapest box is not necessarily the cheapest shipment. A slightly more expensive right-sized carton may reduce void fill and dimensional-weight exposure. Use the tools together rather than optimizing one number in isolation.