Data Transfer Calculator
Find transfer time, required nominal speed or data size. Distinguish bits, bytes, decimal and binary units and include an explicit effective-throughput percentage.
YOUR CALCULATION
Result
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Calculation steps
Work through one step at a time or reveal the complete calculation. The steps use your current inputs.
How to calculate
Convert the entered size to bits and the nominal speed to bits per second. Multiply nominal speed by the entered efficiency, then divide size by that effective speed. Rearrange the same relationship when solving speed or data size.
effective rate = nominal rate × efficiency/100; time = size/effective rate; nominal rate = size/(time × efficiency/100)
Worked example
8 GB is 64,000,000,000 bits. At 100 Mbit/s and 80% effective throughput, the effective speed is 80,000,000 bit/s and the transfer takes 800 s = 13 min 20 s. At 100% it would take 640 s.
Assumptions and input details
One byte is 8 bits. Decimal prefixes use powers of 1,000; binary prefixes such as MiB and GiB use powers of 1,024. The efficiency is your assumption, not an automatic speed test. Times assume a constant sustained rate and omit setup delays, retries and pauses. No file is read or uploaded; only the entered size is used.
References: NIST: binary prefixes and bits/bytes
Unit definitions
Unit selection is independent of language. Each selector contains only units for its physical quantity. Calculations use defined base units internally.
One byte is eight bits. Decimal prefixes (k, M, G, T, P, E) use powers of 1000. Binary prefixes (Ki, Mi, Gi, Ti, Pi, Ei) use powers of 1024. Transfer rates are per second.
Using this calculator
Can I enter my own problem?
Yes. Replace the example values with your own inputs. The result, calculation steps, tables and applicable diagrams update from those inputs. Blank or invalid values clear the result; example values are never silently substituted for missing inputs.
Are the results exact?
Results use floating-point arithmetic and displayed rounding. Read the formula, assumptions and any stated data precision before interpreting the result.
Is my input uploaded?
The calculation runs in your browser. No account, file upload or external AI service is required. Inputs are not saved between page reloads.
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