Download Speed Test
Measure download throughput by streaming a test payload from this website and watch the live rate and progress.
Test interface
Your browser may ask for permission after you press Start.How to use this tool
- Choose a payload size that matches your connection and data allowance.
- Click Start download test and leave the tab in the foreground.
- Watch the live Mbps value and progress bar as data arrives.
- Read the final average and repeat the test to check consistency.
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Technical explanation
The browser fetches a generated binary stream from the same-origin test endpoint and counts bytes as they arrive. Throughput is calculated from the transferred bits divided by the measured transfer time, excluding the initial connection setup where possible.
This measures the path between your browser and this server, not your full broadband capacity. Server bandwidth, CDN caching, Wi-Fi, TCP ramp-up, and other traffic all affect the result. It is an estimate, not a line-certification test.
Troubleshooting
The test fails immediately
Reload the page and check your connection. Some networks block large downloads or require a proxy.
Speed is much lower than my plan
The server or route may be the bottleneck. Close other transfers and try a wired connection.
Speed starts low then rises
TCP slow start and connection setup commonly reduce the first second. The final average is more representative.
The test uses too much data
Choose a smaller payload. On metered connections, avoid repeated large runs.
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Frequently asked questions
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