npm bundle size cost API

Returns an npm package's minified + gzipped byte size, dependency count, tree-shakeable and side-effect-free flags, a derived weight class, and estimated download time on slow 3G / 4G — normalized from Bundlephobia. The value-add is the derived weight classification and download-time estimate over the raw blob. Answers 'how big is this npm package', 'gzip size of lodash', 'is this package tree-shakeable', 'is this dependency heavy'.

Price$0.01per request

MethodPOST

Route/v1/dev/bundle-size

StatusLive

MIME typeapplication/json

Rate limit60/minute

Cache3600s public

devbundlesizenpmbundlephobiagziptree-shakingweight

API URLhttps://x402.hexl.dev/v1/dev/bundle-size

Integration docs

Example request

{
  "package": "react",
  "version": "18.2.0"
}

Example response

{
  "name": "react",
  "version": "18.2.0",
  "minifiedBytes": 6453,
  "gzippedBytes": 2823,
  "minifiedKB": 6.3,
  "gzippedKB": 2.76,
  "dependencyCount": 1,
  "treeShakeable": false,
  "sideEffectFree": false,
  "weightClass": "tiny",
  "downloadTime": {
    "slow3gMs": 55,
    "fast4gMs": 3
  },
  "repository": "https://github.com/facebook/react"
}

Input schema

{
  "type": "object",
  "required": [
    "package"
  ],
  "properties": {
    "package": {
      "type": "string",
      "examples": [
        "react",
        "lodash"
      ]
    },
    "version": {
      "type": "string",
      "examples": [
        "18.2.0"
      ]
    }
  }
}

Output schema

{
  "type": "object",
  "additionalProperties": true
}