tokenowl

A small, dependency-free utility for calculating LLM token usage costs from per-million-token pricing.

Installation

npm install tokenowl

Usage

import { calculateTokenCost } from "tokenowl";

const cost = calculateTokenCost(
  {
    inputTokens: 250_000,
    outputTokens: 100_000,
  },
  {
    inputUsdPerMillion: 3,
    outputUsdPerMillion: 15,
  },
);

console.log(cost);
// {
//   inputCostUsd: 0.75,
//   outputCostUsd: 1.5,
//   totalCostUsd: 2.25
// }

API

calculateTokenCost(usage, pricing)

usage requires non-negative safe integers:

• inputTokens
• outputTokens

pricing requires non-negative finite numbers:

• inputUsdPerMillion
• outputUsdPerMillion

The function returns inputCostUsd, outputCostUsd, and totalCostUsd. Invalid values throw a TypeError.

Status

TokenOwl is in early development. The API may change before version 1.0.0.

License

MIT