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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.

About this tool

Estimate how long a file takes to transfer at a given connection speed — correctly handling bits vs bytes (Mbps vs MB/s) and SI vs binary size units Bandwidth Calculator runs in the browser on DevTools. There is no signup, and your input stays on this device unless the tool explicitly performs a live network lookup.

What this tool does not do

  • Bandwidth Calculator is a free in-browser utility, not a hosted API. It does not keep server-side history and is not a substitute for production verification in your own stack.

How do I use this tool?

  1. How do I use Bandwidth Calculator?

    Open Bandwidth Calculator, enter or paste your input, and copy the result. The page works without an account.

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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