@packrift/dim-weight-calculator

Small dependency-free JavaScript utilities for dimensional weight and billable shipping weight calculations.

Use this package when a checkout extension, warehouse script, rate-shopping tool, or AI agent needs to calculate dimensional weight without pulling in a carrier SDK.

Packrift also hosts no-code versions of these workflows:

• Dimensional weight calculator: https://packrift.com/pages/dimensional-weight-calculator
• Free dimensional weight calculator widget: https://packrift.com/pages/free-dimensional-weight-calculator-widget

Install

npm install @packrift/dim-weight-calculator

Usage

import {
  calculateBillableWeight,
  calculateDimensionalWeight,
  compareDimensionalDivisors,
  parseCartonSize
} from "@packrift/dim-weight-calculator";

const dimensions = parseCartonSize("16 x 12 x 8");

const dimensionalWeight = calculateDimensionalWeight({
  ...dimensions,
  divisor: 139
});

const billable = calculateBillableWeight({
  actualWeight: 9.4,
  dimensions,
  divisor: 139
});

const comparison = compareDimensionalDivisors(dimensions, {
  parcel139: 139,
  parcel166: 166
});

console.log({ dimensionalWeight, billable, comparison });

API

calculateDimensionalWeight(options)

Calculates dimensional weight from package dimensions.

calculateDimensionalWeight({
  length: 16,
  width: 12,
  height: 8,
  divisor: 139,
  round: "ceil"
});

Options:

• length, width, height: positive numbers.
• divisor: positive number. Defaults to 139, a common parcel divisor.
• round: one of "ceil", "floor", "round", or "none". Defaults to "ceil".
• precision: decimal places used with "round". Defaults to 2.

calculateBillableWeight(options)

Returns rounded actual weight, dimensional weight, billable weight, and whether actual or dimensional weight wins.

calculateBillableWeight({
  actualWeight: 9.4,
  dimensions: { length: 16, width: 12, height: 8 },
  divisor: 139
});

compareDimensionalDivisors(dimensions, divisors)

Calculates dimensional weight across multiple divisors and returns results from heaviest to lightest.

compareDimensionalDivisors(
  { length: 16, width: 12, height: 8 },
  { parcel139: 139, parcel166: 166 }
);

parseCartonSize(size)

Parses common carton strings such as "16x12x8" or "16 x 12 x 8" into { length, width, height }.

cubicVolume(dimensions)

Returns length * width * height after validating the dimensions.

normalizeDimensions(dimensions)

Returns a clean numeric { length, width, height } object and throws for invalid values.

Common Divisors

The package exports COMMON_DIM_DIVISORS for convenience:

{
  parcel139: 139,
  parcel166: 166,
  metric5000: 5000,
  metric6000: 6000
}

Always confirm the divisor, rounding rules, and units required by your carrier, contract, or marketplace.

GitHub Pages

docs/index.html contains a static calculator/demo page suitable for GitHub Pages.

Guides

• Carrier divisor reference

License

MIT