𝗦 𝗔 𝗜 𝗭 𝗨 ︲ The real weight of your dependencies. Size is a feature, measure it.

Saizu is a blazingly fast npm package analyzer built with Bun and Hono — no Node.js, no bloat, no compromises. The entire server runs as a single lightweight process with zero unnecessary dependencies.

What it does

Paste any npm package name and Saizu will instantly tell you everything you need to know before adding it to your project:

• Gzip size and install size — the real numbers, not estimates
• File count and type breakdown — see exactly what you're shipping (.js, .d.ts, .mjs, and more) visualized as an interactive distribution bar
• Dependencies — the full list, each one clickable to inspect recursively
• Download time — calculated across 4G, Wi-Fi and Gbit so you know the real-world impact
• Module format — ESM, CommonJS, and TypeScript types availability at a glance
• License — detected directly from the package manifest
• GitHub Badges — copy-paste ready in both Markdown and HTML format, served instantly with no external service latency

Need to choose between two packages? The Compare mode puts them side by side with a detailed diff of every metric so you can make an informed decision.

Why Saizu

Saizu installs the package in an isolated temp directory, measures it, and discards it. The result is cached in-memory for subsequent requests.

No database. No external services. No persistence layer. Just a single process, a temp folder, and an in-memory cache. The whole analysis takes a few seconds and works on any package, any version, any scope.

REST API

Saizu provides a public JSON REST API to consume package metrics programmatically.

• Base URL: https://saizu.dev/api/v1
• Rate Limit: 30 requests per minute per IP.
• CORS: Enabled for all origins.

Endpoints

# 1. Analyze a package
curl "https://saizu.dev/api/v1/package/react"

# 2. Analyze a specific version
curl "https://saizu.dev/api/v1/package/react?version=18.2.0"

# 3. Analyze a scoped package (URL encoded slash or wildcard)
curl "https://saizu.dev/api/v1/package/@tanstack%2Freact-query"
# or
curl "https://saizu.dev/api/v1/package/@tanstack/react-query"

# 4. Analyze a GitHub repo (pre-publish)
curl "https://saizu.dev/api/v1/repo/facebook/react"

# 5. Analyze a GitHub repo with branch and subpath (Monorepo)
curl "https://saizu.dev/api/v1/repo/TanStack/query?branch=v4&subpath=packages/react-query"

# 6. Compare two packages (npm vs npm)
curl "https://saizu.dev/api/v1/compare?a=axios&b=ky"

# 7. Compare npm package vs GitHub repo
curl "https://saizu.dev/api/v1/compare?a=axios&b=github:axios/axios"

# 8. Health check
curl "https://saizu.dev/api/v1/health"

# 9. API Reference
curl "https://saizu.dev/api/v1/"

{
  "name": "@tanstack/react-query",
  "version": "5.90.21",
  "description": "Hooks for managing, caching and syncing asynchronous and remote data in React",
  "license": "MIT",
  "author": "tanstack",
  "gzipSize": 228158,
  "installSize": 734321,
  "fileCount": 325,
  "fileTypes": {
    "md": 4462,
    "other": 1079,
    "json": 4367,
    "tsx": 7511,
    "ts": 54459,
    "cjs": 175377,
    "cts": 70362,
    "map": 297586,
    "js": 48826,
    "dts": 70292
  },
  "dependencies": [
    "@tanstack/query-core",
    "react"
  ],
  "dependencyCount": 2,
  "hasESM": true,
  "hasCJS": true,
  "hasTypes": true,
  "downloadTime": {
    "4g": 31,
    "wifi": 11,
    "gbit": 2
  }
}

Note: the API returns all sizes in pure bytes and download times in milliseconds.

saizu-fast-preview.mp4

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