| Metric | Value |
|---|---|
| Total bytes | {{ format(total_bytes) }} |
| Raw rate (B/s) | {{ format(raw_bps) }} |
| Effective (B/s) | {{ format(eff_bps) }} |
File transfers move binary data across heterogeneous networks where throughput, congestion-control algorithms and protocol framing decide how quickly bytes leave one host and reach another. Bandwidth alone never tells the whole story because segments, acknowledgements and latency all chip away at nominal capacity, extending end-to-end duration.
This calculator converts any combination of file size, link speed and optional protocol overhead into a precise duration. It multiplies unit-normalised byte counts by overhead-adjusted bandwidth, formats the quotient in days, hours, minutes and seconds, and renders complementary tables and interactive charts via a lightweight reactive engine and charting layer.
Use it to plan backups, migration windows or media uploads without guesswork; change a single value to explore “what-if” network scenarios and immediately see their impact on completion time.
Digital links transmit discrete packets whose payload size is fixed by protocol standards and link-layer MTUs. Throughput equals raw channel capacity minus framing, retransmission and flow-control overhead. Because both size and rate are expressed in bytes, a simple ratio yields time. However, unit prefixes vary—decimal for telecommunications, binary for storage—so every value is first normalised to bytes or bytes · s-1.
The interactive charts derive from the same dataset, ensuring numerical consistency: bar columns juxtapose theoretical versus effective throughput while an area plot integrates the effective rate to produce a cumulative-bytes timeline. All computation executes client-side, avoiding server latency and protecting input confidentiality.
| Symbol | Meaning | Unit | Typical Range | Sensitivity |
|---|---|---|---|---|
| v | Numeric file size | B, KB, MB … | 10 B – 10 TB | linear |
| r | Numeric bandwidth | B/s, b/s | 1 Kbps – 400 Gbps | inverse |
| o | Protocol overhead | % | 0 – 50 | moderate |
| S | Total bytes | B | derived | n/a |
| R | Effective rate | B/s | derived | n/a |
A 1 GB (1 × 109 B) file over a 100 Mbps line with 10 % overhead:
The result rounds to 1 min 29 s.
All arithmetic uses IEEE-754 double precision; rounding errors stay below ±0.01 %. Complexity is O(1) for core maths and O(n) for timeline sampling where n = 50. The reactive layer throttles recalculations to 40 ms, balancing responsiveness with CPU usage. The tool complies with HTML5 offline capability and needs no additional API permissions.
The calculator updates instantly, so a single change shows ripple effects across every metric.
No. The tool normalises units regardless of case.
All calculations run entirely in your browser; nothing is transmitted or persisted.
Different protocols waste varying fractions of raw bandwidth; a percentage models that loss without deep packet inspection.
Enter the average observed throughput to obtain a reasonable estimate.
Use your browser’s built-in Save image or screenshot function; charts regenerate quickly if resized.