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Free network tool
Bandwidth calculator
Transfer time with protocol overhead, and the bandwidth-delay product that caps TCP throughput. Runs entirely in your browser — no project or account is required.
Input
Transfer size
Link rate
Protocol overhead (%)~5% is typical for bulk TCP over Ethernet.
Round-trip time (ms)Used for the bandwidth-delay product.
Transfer time14m 2sWith overhead
Theoretical800.0sNo overhead
Effective rate950 Mbps
Bandwidth-delay product
Data in flight on the link. A TCP window smaller than this caps throughput no matter how much bandwidth there is.
- In flight
- 4882.8 KB
- Bytes
- 5,000,000
Exceeds the 64 KB TCP window limit — window scaling (RFC 7323) is required to fill this link.