Convert MB/s to Mbps – Bandwidth Converter
This converter translates data transfer rates expressed in megabytes per second (MB/s) to megabits per second (Mbps). It explicitly handles the two common interpretations of "mega"—the SI decimal prefix (10^6) and the binary prefix (MiB = 2^20 bytes)—so you get accurate, actionable values for measurement, planning, or reporting.
Network equipment, speed tests, and storage tools may report rates using different definitions. By default this converter uses the SI mega (1 MB = 1,000,000 bytes) unless you specify binary (MiB) considerations; see the methodology and examples for the alternate calculation.
Practical guidance is provided on measurement limits, protocol overhead, and regulatory context so you can interpret converted values correctly when comparing advertised ISP speeds, benchmarking links, or sizing transfers.
Interactive Converter
Convert between megabyte per second and megabit per second with precision rounding.
Quick reference table
| Megabyte per Second | Megabit per Second |
|---|---|
| 1 MB/s | 1 Mbps |
| 5 MB/s | 5 Mbps |
| 10 MB/s | 10 Mbps |
| 25 MB/s | 25 Mbps |
| 50 MB/s | 50 Mbps |
| 100 MB/s | 100 Mbps |
Methodology
Base relationship: 1 byte = 8 bits. Converting MB/s to Mbps therefore starts by multiplying bytes per second by 8 to get bits per second, then applying the appropriate mega (10^6) scale.
Two common definitions matter: the SI (decimal) megabyte where 1 MB = 1,000,000 bytes, and the binary mebibyte where 1 MiB = 1,048,576 bytes. Use the decimal route for ISP advertising and most networking contexts; use binary when working with operating-system or file-size tools that report MiB.
Measurement caveats: observed throughput will usually be lower than raw line rate because of protocol overhead (Ethernet/IP/TCP headers, encapsulation, encryption), queueing, and measurement tool limitations. For regulatory and consumer-facing comparisons, refer to government broadband measurement guidance and NIST unit definitions.
Worked examples
Decimal example: 1.0 MB/s → 1.0 × 8 = 8.0 Mbps.
Binary example: 1.0 MiB/s → 1.0 × 8.388608 = 8.388608 Mbps.
Practical example: A 50 MB/s file transfer (reported by some file managers) corresponds to ~400 Mbps using decimal units (50 × 8 = 400 Mbps). If that 50 value were MiB/s, the equivalent would be ~419.4304 Mbps (50 × 8.388608).
Further resources
Expert Q&A
What is the simple rule of thumb to convert MB/s to Mbps?
Multiply MB/s by 8 when MB uses the decimal mega (1 MB = 1,000,000 bytes). That yields megabits per second (Mbps).
Why do some tools show slightly different numbers for the same transfer?
Differences come from whether the tool reports decimal MB (10^6 bytes) or binary MiB (2^20 bytes), from protocol and transport overhead (headers, retransmits, encryption), and from measurement methodology (averaging window, sampling).
Which definition should I use when comparing my ISP speed?
Use the decimal (SI) definition—ISPs and most regulatory guidance report speeds in decimal units (megabits where 1 Mbps = 1,000,000 bits). See FCC and NTIA guidance for consumer broadband measurement practices.
How should I handle protocol overhead and real-world throughput?
Expect usable throughput to be lower than raw converted values. Account for ~2–10% overhead for headers in simple cases and substantially more when using tunneling, VPNs, or encryption. For capacity planning, add margin and validate with controlled tests using iperf or similar tools.
How precise are these conversions and how should I round?
Use at least 3–4 significant digits when converting for engineering work. For consumer-facing displays, round to 1–2 decimal places. Document whether values use SI or binary prefixes to avoid ambiguity.
What is the exact numeric factor for MiB to Mbps?
1 MiB/s = 1,048,576 bytes/s × 8 = 8,388,608 bits/s, which equals 8.388608 Mbps when 1 Mbps = 1,000,000 bits.
Where can I find authoritative references for unit prefixes and measurement guidance?
Refer to NIST for SI and prefix definitions and to government broadband measurement guides for consumer-facing testing practices. These sources explain the unit conventions and recommended measurement approaches.
Sources & citations
- NIST Guide to the SI (Special Publication 811) — https://www.nist.gov/pml/special-publication-811
- NIST Reference: Metric Prefixes and Unit Conversions — https://physics.nist.gov/cuu/Units/prefixes.html
- NTIA blog: What Does Mbps Mean? — https://www.ntia.doc.gov/blog/2020/what-does-mbps-mean
- FCC: Broadband Speed Tests and Consumer Guidance — https://www.fcc.gov/consumers/guides/broadband-speed-tests
- MIT OpenCourseWare — Computer Networks (reference material on throughput and overhead) — https://ocw.mit.edu/courses/6-829-computer-networks-fall-2002/