Guess the Speed

Why this exists

Speed test nights on the living-room TV became our family game night, with everyone shouting a guess before I press go. My kids get it right every time, and Dad loses on purpose. I started out in performance testing, moved into development, and turned that ritual into a game other families can play; here is the story.

How a round works

1. Add players and choose a face for each one.
2. Everyone locks a secret download and upload guess.
3. Run a real speed test against Cloudflare's network.
4. Compare guesses with the result and score the closest players.

Features

Scoring

Rule	How it works
Place points	First place earns 3 points, second place 2, and third place 1.
Spot-on bonus	Earn +1 point for each download or upload guess within 5% of its measured speed.
50% cutoff	An average miss over 50% earns no place points; the next closest eligible guess moves up.
Ties	Shared points are the default; the alternate tie-break compares download miss, then upload miss.
Rounds	Three rounds by default, with set-length and endless options.

Privacy by design

• Single-screen game settings, player names, and scores stay in this browser's local storage.
• Room names, faces, guesses, and scores are deleted after six hours without activity.
• The play counter stores totals only. Cloudflare Web Analytics is cookieless.
• Sharing uses your device's share sheet or clipboard.
• The speed test runs in your browser against Cloudflare's network.

Read the privacy page.

Guides on the site

• Family game night ideas that use your Wi-Fi
• How does the real speed test work?
• How Much Internet Speed Do I Need?
• How do you play Guess the Speed?
• Internet speed 101
• Internet speed lesson for kids: a 30-minute classroom activity
• Mbps to MB/s Converter
• The speed test guessing game
• What Is a Good Internet Speed in 2026?

How it's built

• Astro and TypeScript serve the static site on Cloudflare Workers.
• @cloudflare/speedtest measures the connection in the browser.
• GameRoom Durable Object manages multiplayer rooms with WebSocket hibernation; PlayStats keeps the aggregate play counter.
• Game and scoring rules live in src/lib and are covered by Vitest.

src/
  lib/       game, scoring, room, and speed-test logic
  pages/     the game, guides, story, and privacy page
  scripts/   browser interactions
  styles/    themes and responsive layout
worker/      GameRoom and PlayStats Durable Objects
public/      icons and static assets

Local development

npm install
npm run dev

Use the Worker locally to exercise rooms and play stats:

npm run dev:worker

Useful commands:

npm run check
npm test
npm run format
npm run format:check
npm run build
npm run preview

For a short simulated speed test, append ?mock=1. Use ?dev=1 to open Dev diagnostics or ?tv=1 to use the TV layout.

Deploy

Deploy with Cloudflare Workers Builds. wrangler.jsonc runs npm run build before npx wrangler deploy and uploads dist as static assets, so the dashboard build command can stay empty. Durable Object migrations for GameRoom and PlayStats run as part of the deploy.

To enable optional Cloudflare Web Analytics, configure PUBLIC_CF_BEACON_TOKEN in the Cloudflare build environment. Without the token, the analytics beacon is not included.