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# Bandwidth and download-time calculator

How long a file takes at a given line rate — exact fractional seconds, decimal and binary unit bases kept separate, and no fake efficiency percentage.
exact BigInt fractions · wire time only — overhead is not modeled and not pretendedCalculateClearSize unitRate unit

6m 43 s + 1419777/1953125s

Exactly 403 + 1419777/1953125 seconds ( 12500000 bytes/second average at this rate).

Wire time at the stated line rate. Protocol overhead (TCP/IP/Ethernet framing), windowing, and competing traffic are NOT modeled — real transfers take longer; no fake efficiency percentage is applied.

- Decimal (SI): kB, MB, GB = powers of 1000; kbit/s, Mbit/s likewise — the units ISPs advertise.
- Binary (IEC): KiB, MiB, GiB = powers of 1024 — the units file managers show. The same number in the two bases is a different transfer; the picker states which you chose.
- Rates are bits, sizes are bytes — the factor of 8 is exact BigInt arithmetic, and fractional inputs stay exact fractions (1 MiB at 1 Mbit/s is 8.388608 s, not 8.4).
- Wire time means the line-rate ideal. TCP/IP framing, windowing, TLS handshakes, and competing traffic all add time; inventing an "efficiency" number would be lying with decimals, so the tool refuses to.
Done

Finished here in the tab. Nothing was uploaded.

exact rational arithmetic — the fraction of a second is printed, not rounded away

## Next door in Network

- [Unit converter](/converters/units)
- [Duration converter](/time/duration-converter)
[All network tools](/network)

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Canonical HTML: https://nutter.tools/network/bandwidth
Markdown version: https://nutter.tools/network/bandwidth/index.md
Plain-text version: https://nutter.tools/network/bandwidth/index.txt
Agent index: https://nutter.tools/llms.txt

