Network Information & Adaptive Loading Tester
The Network Information API (navigator.connection) reveals the user's
effective connection type, bandwidth, and data-saver preference — perfect for building
adaptive, data-saving experiences. Read your live network state, get loading
recommendations, and generate test mocks.
Tool interface
📶 Live Network State
Reads navigator.connection and updates on change.
🧪 Test Mock Generator
Generate a navigator.connection mock for your unit tests (Jest / Vitest).
Introduction
Billions of users are on slow or metered connections. The Network Information API lets you adapt your experience to their reality — but it's easy to overlook. This tester shows you exactly what your browser reports and helps you build and test adaptive loading logic.
How It Works
- Reads
navigator.connectionfor effectiveType, downlink, rtt, and saveData. - Listens for the
changeevent to reflect network shifts in real time. - Generates adaptive-loading recommendations based on connection quality.
- Produces a copy-ready mock for Jest/Vitest test suites.
Privacy
Network data is read and rendered locally in your browser. Nothing is transmitted. No API calls, no tracking.
Limitations
- The Network Information API is Chromium-only; Safari and Firefox return nothing.
- Values are estimates, not precise measurements.
- Some properties (like
type) may be unavailable or restricted.
FAQ
Why is everything "unknown"?
You're likely on Safari or Firefox, which don't implement the Network Information API. Feature-detect and fall back in your code.
Is my network data uploaded?
No. Everything is read locally in your browser. Nothing is transmitted.