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0% = Theoretical, 10% = Ethernet/Fiber, 30%+ = Wi-Fi/LTE
Estimated Transfer Time
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About

Why does a 1 Gbps internet connection never download at 125 MB/s? The answer lies in Network Overhead. Every piece of data sent over the internet is wrapped in headers (TCP/IP), frame checks, and acknowledgments. Additionally, network congestion and protocol inefficiencies often reduce real-world throughput by 6% to 15%.

This calculator bridges the gap between marketing claims and reality. It converts your ISP's speed (measured in bits) to file storage (measured in Bytes) and subtracts a configurable overhead percentage. It's designed to give you an accurate "Time to Transfer" for large assets like 100GB game downloads or 4K video streams.

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Formulas

The formula for time (t) converts file size (S) to bits, divides by bandwidth (BW), and adjusts for overhead (O):

t = Sbytes × 8BWbps × (1 O%)

Note: 1 Byte = 8 bits. Marketing speeds are always in bits (b), while files are in Bytes (B).

Reference Data

ConnectionAdv. SpeedReal Max (approx)10GB File Time
DSL / ADSL10 Mbps1.1 MB/s~2.5 Hours
4G LTE50 Mbps5.5 MB/s~30 Mins
Wi-Fi 5 (AC)400 Mbps45 MB/s~3.7 Mins
Fiber / 1GbE1000 Mbps112 MB/s~1.5 Mins
USB 3.0 / 5GbE5000 Mbps450 MB/s~22 Secs
10GbE LAN10,000 Mbps1150 MB/s~9 Secs

Frequently Asked Questions

Capitalization matters. Mbps = Megabits per second (Speed). MBps = MegaBytes per second (Storage). Since 1 Byte = 8 bits, 100 Mbps is only 12.5 MBps.
TCP/IP headers consume about 3-5% of bandwidth. Additional factors like Ethernet framing, Wi-Fi interference, and router processing add another 5-10%. A 10% reduction provides a safe, realistic estimate for wired connections.
Yes, but Wi-Fi overhead is often much higher (30-50%) due to signal interference, distance, and half-duplex communication (it can't send and receive simultaneously like a cable).