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Bandwidth Calculator

Bandwidth Calculator

Estimate how long a file takes to transfer at a given connection speed — computed in your browser

Inputs

File size and connection speed

Note: bits (Mbps) vs bytes (MB/s) differ by 8×. Sizes use SI (KB=1000) or binary (KiB=1024) as selected. Estimate excludes protocol overhead.

Related guides

Bits vs Bytes: Why Your Download Estimate Is Off by 8×

The classic mix-up between megabits and megabytes, plus SI vs binary units — and how to estimate transfer time correctly.

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