Test your real-world international internet speed with production-grade performance

🚀 Try it live • 🌍 Africa-Optimized • 📚 Learn More

SpeedCheck measures your real-world international connectivity with a distributed global architecture:

• ⚡ Real-time Testing - Live gauge with download, upload, latency & jitter using Web Workers
• 📊 Variance Graph - Real-time speed visualization with bufferbloat detection (stability analysis)
• 🎯 Measurement Quality - Confidence scoring (0-100%) with detailed quality indicators
• 🧪 Physics-Aware Analysis - Educational context explaining latency, jitter, and speed results based on distance and routing
• 📊 Transparent Metrics - Sample counts, outlier detection, measurement methodology visible
• 🌍 Geographic Context - Distance calculation, network type detection, server location display
• 📈 History & Statistics - Local storage with averages, trends, and test count (privacy-focused)
• 🛠️ PWA Support - Add to home screen for app-like experience with background sync
• 🔒 Zero Dependencies - Pure vanilla JavaScript, fast loading, secure by design
• 📚 Comprehensive Audit - Built-in monitoring system for performance & security validation
• 🎓 Educational Content - Learn page explaining internet concepts and performance metrics
• ♿ Accessibility - Screen reader support, ARIA labels, keyboard navigation
• 🔬 Scientific Accuracy - TCP slow start compensation with statistical outlier removal (MAD)
• 💎 Visual Polish - Smooth animations, loading skeletons, button interactions, tabular numbers
• 🌐 Dual Deployment - Europe (Railway) + Africa (Cloudflare) for optimized global access
• 🛡️ Production Security - HSTS, CSP, security headers, X-Powered-By removal, helmet.js protection

• Europe/Asia/Americas: speed-test.up.railway.app
• Africa Optimized: speed-test-ahc.pages.dev

# Comprehensive health check (11 test phases)
./audit.sh

# Clone repository
git clone https://github.com/ny-collins/internet_speed_test.git
cd internet_speed_test

# Install dependencies
cd backend && npm install
cd ../frontend && npm install

# Run locally
cd backend && npm run dev  # API server on :3000
cd ../frontend && npm start  # Frontend on :8080

⚠️ Important: Test against live deployments for accurate results. Local testing shows unrealistic speeds.

SpeedCheck uses a production-grade distributed architecture with Web Workers for optimal performance:

• Frontend: Pure HTML/CSS/JS with Web Workers for heavy computation
• Backend: Node.js + Express API with pre-generated buffers for CPU efficiency
• Deployment: Railway (EU West) + Cloudflare Pages (Africa regional)
• Audit System: Comprehensive 11-phase monitoring and health checks

• 🧵 Web Workers: Heavy stream processing off main thread prevents UI blocking
• ⚡ Progressive Enhancement: Device-aware update intervals (50-200ms)
• 🧠 Memory Management: Pre-allocated buffers prevent GC pauses during tests
• 🎯 Idle Task Scheduling: Non-critical monitoring during browser idle periods
• 🔄 Request Caching: 24-hour CORS preflight caching for instant repeated tests

┌─────────────────┐    ┌─────────────────┐
│   Nairobi       │    │   Amsterdam     │
│   (Cloudflare)  │◄──►│   (Railway)     │
│   Frontend      │    │   Backend       │
│   14ms latency  │    │   180ms latency │
└─────────────────┘    └─────────────────┘
         ▲                       ▲
         │ 3x faster for         │ Global users
         │ African users         │

SpeedCheck includes a comprehensive 11-phase audit system for production monitoring:

./audit.sh  # Run complete system health check

Audit Coverage:

• ✅ Geographical Latency - User perspective performance
• ✅ Infrastructure Forensics - Cloudflare location verification
• ✅ Backend Handshake Analysis - Connection overhead measurement
• ✅ Security & CORS Compliance - Access control validation
• ✅ Cache Optimization - Preflight caching verification
• ✅ Performance Deep Dive - Response consistency & cold starts
• ✅ Security Headers & SSL - Certificate & header validation (HSTS, CSP, X-Frame-Options)
• ✅ Network & Protocol Tests - IPv6, HTTP/2, compression
• ✅ Load & Stress Testing - Concurrent requests & rate limiting
• ✅ Error Handling & Edge Cases - Robustness validation
• ✅ Frontend Specific Tests - SEO, caching, page optimization

• 🧪 Physics-Aware Analysis - Educational explanations replacing subjective quality badges (speed-of-light calculations, routing context)
• 🎨 UI Refinements - 45:55 split ratio, secondary metrics layout (compact ping/jitter), transparent gauge styling
• 📊 Complete Graph History - Removed 50-sample limit, all data shown with horizontal compression
• 🐛 Critical Fixes - JavaScript selectors updated for secondary metrics, eslint compliance achieved
• 💎 Gauge Sizing - Increased to 360px for better visual impact, resolved CSS conflicts

• 🎨 Desktop UI Overhaul - Two-column layout with sticky gauge and hierarchical results matrix
• 📊 Real-time Variance Graph - Canvas-based speed visualization with bufferbloat detection (stability <10% excellent, >30% poor)
• 📖 Interactive Accordion Footer - 6 expandable sections for methodology, privacy, and educational content
• 🎯 Enhanced Start Button - 360px circular gradient design with pulse animation
• ⚡ Real-time Data Collection - Rolling buffer at 100ms intervals for smooth graph updates

• 🔬 Scientific Measurement Accuracy - TCP slow start compensation with byte tracking for professional-grade results
• 📈 Bufferbloat Detection - Loaded latency measurement during active transfers for network quality analysis
• ⚡ Enhanced Responsiveness - Asynchronous completion handling prevents UI freezing during test results
• 🐛 Critical Bug Fixes - Race condition resolution, cancellation logic fix, ES module integration

• 🚀 Production-Grade Architecture - Web Workers implementation for smooth 60fps UI during speed tests
• 📊 Comprehensive Audit System - 11-phase automated monitoring and health checks
• 🌍 Geographic Optimization - Dual deployment: Europe (Railway) + Africa (Cloudflare)

• ⚡ Performance Optimizations - Progressive enhancement, idle task scheduling, frame monitoring
• 🛡️ Security Improvements - PWA update banner security fix
• 🔧 Critical Bug Fixes - Module imports, speed calculations, sparkline rendering

Measurement Quality Visibility

• Confidence scoring (0-100%) for all test types (download/upload/latency)
• Color-coded indicators: High (≥85%), Medium (70-84%), Low (50-69%), Very Low (<50%)
• Detailed modals with sample counts, outlier info, and methodology
• 5-factor confidence calculation for speed tests, 3-factor for latency

Geographic Context

• Real-time distance calculation to Amsterdam server
• Network type detection (WiFi, 4G, etc.) via Network Information API
• Test context panel with server location, distance, connection, timestamp
• Geolocation integration with Great Circle distance formula

Local History & Statistics

• localStorage-based history (50 test limit)
• Privacy notice: "History stored locally on this device only"
• Aggregate statistics: average download/upload/latency, test count
• Chart visualization with export/clear functionality

Learn Page Integration

• Tooltip helper functions for contextual education
• Smooth navigation from results to learning content
• Enhanced accessibility and mobile responsiveness

Visual Polish

• Tabular numerals for consistent number display
• Smooth number counting animations with easing
• Button ripple effects and micro-interactions
• Loading skeletons with shimmer animations
• Professional tooltip system with positioning
• Pulse animations for loading states

See DEPLOYMENT_CHECKLIST.md for complete implementation details.

MIT License - see LICENSE for details.

• Architecture - System architecture, test flow, and API reference
• Design - Design decisions and technical rationale
• Deployment - Deployment guide and environment configuration
• Security - Security architecture and audit results
• Changelog - Version history and release notes