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.

Updated Nov 2, 2025QA PASS — golden 25 / edge 120Run golden-edge-2026-01-23

Governance

Record 0674b777f042 • Reviewed by Fidamen Standards Committee

Interactive Converter

Convert between megabyte per second and megabit per second with precision rounding.

Megabyte per Second (MB/s)Megabit per Second (Mbps)

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).

F.A.Q.

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/
IEC 80000-13:2008 — Information science and technology — https://www.iso.org/standard/31898.html

Further resources

Related tools

External guidance

Versioning & Change Control

Audit record (versions, QA runs, reviewer sign-off, and evidence).

Record ID: 0674b777f042

What changed (latest)

v1.0.0 • 2025-11-02 • MINOR

Initial publication and governance baseline.

Why: Published with reviewed formulas, unit definitions, and UX controls.

Public QA status

PASS — golden 25 + edge 120

Last run: 2026-01-23 • Run: golden-edge-2026-01-23

Engine

v1.0.0

Data

Baseline (no external datasets)

Content

v1.0.0

Governance

Last updated: Nov 2, 2025

Reviewed by: Fidamen Standards Committee (Review board)

Credentials: Internal QA

Risk level: low

Reviewer profile (entity)

Fidamen Standards Committee

Review board

Internal QA

Entity ID: https://fidamen.com/reviewers/fidamen-standards-committee#person

Semantic versioning

MAJOR: Calculation outputs can change for the same inputs (formula, rounding policy, assumptions).
MINOR: New features or fields that do not change existing outputs for the same inputs.
PATCH: Bug fixes, copy edits, or accessibility changes that do not change intended outputs except for previously incorrect cases.

Review protocol

Verify formulas and unit definitions against primary standards or datasets.
Run golden-case regression suite and edge-case suite.
Record reviewer sign-off with credentials and scope.
Document assumptions, limitations, and jurisdiction applicability.

Assumptions & limitations

Uses exact unit definitions from the Fidamen conversion library.
Internal calculations use double precision; display rounding follows the unit's configured decimal places.
Not a substitute for calibrated instruments in regulated contexts.
Jurisdiction-specific rules may require official guidance.

Change log

v1.0.0 • 2025-11-02 • MINOR

Initial publication and governance baseline.

Why: Published with reviewed formulas, unit definitions, and UX controls.

Areas: engine, content, ui • Reviewer: Fidamen Standards Committee • Entry ID: b83633183290