Test Configuration
Performance Metrics
Lazy Load Tester - Performance Testing Tool
Test lazy loading performance with network simulation and detailed metrics analysis
Key Features
Network Simulation
Test with 3G, 4G, 5G, and WiFi profiles
Performance Metrics
CPU, memory, and load time tracking
Timeline Analysis
Detailed loading timeline and metrics
Export Data
Download metrics as JSON for analysis
What is Lazy Load Tester?
Lazy Load Tester is a comprehensive performance testing tool that simulates lazy loading behavior with various network conditions. It provides detailed metrics on loading performance, CPU usage, and memory consumption.
How to Use
- Set the number of images to test (5-100)
- Select a network profile or create a custom one
- Click "Start Test" to begin the simulation
- Monitor the performance metrics in real-time
- Export the results for detailed analysis
Network Profiles
3G
0.4 Mbps download. Simulates slow mobile networks with high latency.
4G LTE
10 Mbps download. Typical mobile network speed with moderate latency.
5G
100 Mbps download. Fast mobile network with low latency.
WiFi
50 Mbps download. Typical home/office WiFi speeds.
Frequently Asked Questions
What is lazy loading?
Lazy loading defers loading images until they're needed, improving initial page load performance.
How does Intersection Observer work?
Intersection Observer detects when elements enter the viewport and triggers loading at that moment.
What network speeds should I test?
Test with 3G, 4G, and WiFi to understand performance across different user conditions.
What are good performance targets?
Aim for LCP < 2.5s, FID < 100ms, and CLS < 0.1 according to Core Web Vitals.
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Use ToolRelated guides
Read the how-to, then come back to this tool when you are ready to run it locally.