Data Rate Converter

Turn a bandwidth figure into the unit you actually wanted — megabits into megabytes, GiB/s into Gbit/s.

Runs on your deviceConvertersWorkingNo account needed

What this tool does

Data Rate Converter holds fifteen throughput units on one scale — bit/s through Tbit/s, B/s through TB/s, and the binary Kibit/s, Mibit/s, KiB/s, MiB/s and GiB/s — and routes every line through a single base of bits per second. A line reads as a value, an optional unit and an optional target, so "25 MB/s to Mbit/s" is a complete instruction on its own, while a bare "100" falls back to the From and To dropdowns. Paste a column of figures and each line is converted in turn.

The conversion most people come for is bits to bytes. Network gear, broadband packages and interface specifications are quoted in bits per second; file managers, backup tools and download progress bars count bytes. Eight bits to the byte is the whole of the arithmetic, which is why a 100 Mbit/s connection tops out at 12.5 MB/s and a 6 Gbit/s link at 750 MB/s. Prefixes are the second half of the job: kB/s, MB/s and GB/s are 1000-based here, KiB/s, MiB/s and GiB/s are 1024-based, and both families sit in the same list so you can cross between them.

Two-letter shorthand is where this can bite, and it is worth knowing before you trust a line. A typed unit is matched case-sensitively against the printed symbol first and only then case-insensitively against the unit names and their aliases, so MB/s, Mb/s and mb/s all land on megabytes per second, while kb/s, KB/s and Kb/s all land on kilobits — only the exact spelling kB/s reads as kilobytes. The kilo row is the odd one out: gb/s and tb/s follow mb/s into bytes, so the same shorthand does not mean the same thing at every prefix. Mbps, and even MBps, come out as megabits. When a figure matters, write Mbit/s or MB/s in full, or type the number alone and choose the units from the dropdowns, where every label names the unit in words.

The arithmetic is exact and nothing beyond it is modelled. A 100 Mbit/s line does not hand you 12.5 MB/s of file: Ethernet framing, IP and TCP headers, retransmissions and the coding on the physical link all take a share, and a serial link that wraps each byte in start and stop bits spends ten bits per byte rather than eight. This converts the number you type. It does not measure your connection, and it will not work out how long a transfer takes — divide the size by the rate for that, with Storage Size Calculator alongside if the size needs converting too. The work happens in your browser, so nothing is uploaded and the page still converts with the network off.

How to use it

  1. Type the rate. One value per line. Thousands separators, exponent notation such as 1e3, and simple fractions like 1/2 are all accepted, so figures pasted out of a spreadsheet or a datasheet go straight in.
  2. Name the units, or leave them to the dropdowns. From and To list all fifteen units by name and symbol. A unit typed after the number replaces the From setting for that line only, and "to", "as", "into" or an arrow introduces the target that replaces To: "1 GB/s to Gbit/s".
  3. Switch To to All units (table). One rate is then expanded into every unit at once — decimal and binary, bits and bytes — which is the quickest way to see where a download speed sits across the whole scale.
  4. Set the precision. Automatic keeps up to ten significant digits and falls back to exponential form for very small results: 1 bit/s comes out as 1.25e-7 MB/s. The fixed menu jumps 0, 1, 2, 3, 4, 6, 8 decimals — there is no five- or seven-decimal entry — and a fixed setting rounds the figure you typed as well as the answer, so a column lines up on both sides.

Processing & privacy

Runs on your device. Your file is processed directly in this browser.

Common use cases

Checking what a broadband package really gives you

A 500 Mbit/s line is 62.5 MB/s at the absolute ceiling, before any protocol overhead — which is the number worth comparing against what the download manager reports.

Reading a hardware specification

Drives, buses and NICs are advertised in Gbit/s while benchmarks report MB/s or MiB/s. Converting both to one unit is what makes the two figures comparable.

Sizing a backup or upload window

Convert the uplink into MB/s first, then divide the archive size by it, so the estimate is in the same units as the file you are about to send.

Reconciling a monitoring graph with a transfer log

Interface counters plot bit/s, rsync and browsers print MiB/s. One conversion tells you whether the two are describing the same traffic or a real discrepancy.

Questions

Why is 100 Mbps only 12.5 MB/s?
Because a byte is eight bits. The connection is sold in megabits per second and the download is counted in megabytes per second, so the figure divides by eight before anything else is taken off it.
Should I type Mb/s or Mbit/s?
Mbit/s, or Mbps, when you mean megabits. Mb/s and mb/s are both read as megabytes per second here, so the shorthand that looks like megabits is not treated as such. The dropdowns are unambiguous where a typed unit is not.
Does it use 1000 or 1024?
Both, as separate units. kB/s, MB/s, GB/s and TB/s step by 1000; KiB/s, MiB/s and GiB/s step by 1024, and Kibit/s and Mibit/s do the same for bits. The binary set stops there — there is no gibibit or tebibyte entry to pick.
Will the converted number match my actual transfer speed?
No, and it is not meant to. Framing, headers and retransmissions come out of the advertised rate, so the converted figure is the ceiling rather than the throughput you will observe.
Can it tell me how long a 4 GB file will take?
Not directly — it converts rates, not durations. Convert the rate to bytes per second, then divide the file size by it; Storage Size Calculator handles the size side if that needs converting as well.
Do the rates I type go anywhere?
No. The unit tables and the parser are part of the page, so conversion happens in this browser tab and the numbers you type are not transmitted or stored. It keeps working offline.

Related tools