CalcaTools

Bits Calculator | Convert bits, bytes & common data units

Convert data sizes between bits, bytes and every decimal and binary multiple — kilobits to terabytes, Kib to TiB — with the 1024-versus-1000 difference shown. Understand why a 1 TB drive shows 931 GB and convert network speeds, storage and files with the exact factors applied.

Last updated: June 2026 · Free · No sign-up required

Results

Enter values above and click Calculate to see your result instantly.

What is the Bits Calculator?

A data-size converter that moves between bits, bytes and every common multiple — kilobits, kilobytes, MB, GB, TB and the binary units KiB, MiB and GiB. It also explains the classic mystery: a “1 TB” drive is 931 GiB, because drive makers count powers of 1,000 while your OS counts powers of 1,024.

How to use the Bits Calculator

  1. Enter the data size.
  2. Pick its unit (bits, bytes, KB, MB, GB, TB, KiB, MiB, GiB).
  3. Read the value in every other unit instantly.

Quick reference

UnitEquals
1 byte8 bits
1 KB (kilobyte)1,000 bytes
1 KiB (kibibyte)1,024 bytes
1 MB1,000,000 bytes
1 GB8,000,000,000 bits
1 TB931.32 GiB

info Bits Calculator

Free converters calculator — enter your numbers and get an instant, accurate result.

info Private by design

Everything runs locally in your browser. No uploads, no accounts, no tracking.

info Works everywhere

Fully responsive and mobile-friendly — calculate on any device, any time.

info Educational

Includes the formula and step-by-step explanation so you understand the math, not just the answer.

Interpretation guide

ContextWhich unit is meant
Internet speed (100 Mbps)Megabits per second — divide by 8 for MB/s
Drive capacity on the boxDecimal GB/TB (powers of 1,000)
Capacity Windows reportsBinary GiB shown as 'GB' (powers of 1,024)
RAMTrue binary — 16 GB RAM is 16 GiB

lightbulb Worked example

Let's say you are using the Bits Calculator. Converts data sizes between bits, bytes and every decimal and binary multiple from kilobits to terabytes. Enter the values that match your situation into the input fields and press calculate — using realistic numbers makes the result directly useful for you.

Result: The calculator instantly applies the formula bits = value × unit factor; 1 byte = 8 bits; KB/MB/GB use ×1,000 steps, KiB/MiB/GiB use ×1,024 steps and returns the result with appropriate precision.

What this means: Read the result in the context of what you are measuring. The step-by-step breakdown lets you confirm the math and understand which input most affects the outcome.

Formula & methodology

Formula: bits = value × unit factor; 1 byte = 8 bits; KB/MB/GB use ×1,000 steps, KiB/MiB/GiB use ×1,024 steps

The Bits Calculator is built on a well-established calculation method. It uses the formula bits = value × unit factor; 1 byte = 8 bits; KB/MB/GB use ×1,000 steps, KiB/MiB/GiB use ×1,024 steps to turn your inputs into a reliable result. Converts data sizes between bits, bytes and every decimal and binary multiple from kilobits to terabytes. The steps are shown on the page so you can follow the reasoning from input to output.

  1. The input is converted to bits (1 byte = 8 bits; decimal prefixes step ×1,000, binary prefixes ×1,024).
  2. The bit total is divided by each target unit's factor.

Worked example: a '1 TB' drive is 8 × 10¹² bits = 10¹² bytes, which is 10¹² ÷ 1,024³ = 931.32 GiB — that's the whole mystery of the 'missing' 69 GB. And a 100 Mbps connection moves 100 ÷ 8 = 12.5 MB/s at best.

Authoritative source: U.S. National Institute of Standards and Technology

Frequently asked questions

How many bits are in a byte?
The Bits Calculator is free, private, and accurate: it runs entirely in your browser (no uploads, no accounts), applies the standard calculation, and explains each step so you can verify the result. Converts data sizes between bits, bytes and every decimal and binary multiple from kilobits to terabytes. There is no limit on usage, and it works on any device.
Why does my 1 TB drive only show 931 GB?
Drive manufacturers use DECIMAL units — 1 TB = 1,000 GB = 1,000,000,000,000 bytes — while operating systems display BINARY units: 1 TiB = 1,024 GiB = 1,099,511,627,776 bytes. A '1 TB' drive holds 10¹² bytes, which is 931 GiB. The difference (the missing 69 GB) is not lost space, just two different unit systems. The calculator shows both.
What is the difference between Mbps and MB/s?
Mbps is megabits per second (network speed, lowercase b), and MB/s is megabytes per second (file transfer, uppercase B). One byte = 8 bits, so 100 Mbps = 12.5 MB/s. The calculator converts between them — divide Mbps by 8 for MB/s. This is the most common unit confusion in networking and downloads.
What is a kibibyte (KiB)?
A kibibyte is 1,024 bytes — the binary unit introduced to end the ambiguity where 'kilobyte' meant either 1,000 or 1,024 bytes. KiB, MiB, and GiB use powers of 1024, while KB, MB, and GB officially mean powers of 1000 (decimal). Operating systems traditionally use binary units but label them KB/MB/GB, which is why the numbers look different from drive packaging.
How many bytes is a gigabyte?
In the decimal system, 1 GB = 1,000,000,000 bytes (10⁹); in the binary system, 1 GiB = 1,073,741,824 bytes (2³⁰). The 7.4% difference between them is the source of the famous 'missing space' on drives. The calculator converts between GB and GiB explicitly so you always know which count you are looking at.
What does the Bits Calculator do?
Converts data sizes between bits, bytes and every decimal and binary multiple from kilobits to terabytes. The calculator takes your inputs, applies the standard calculation, and returns a clear result so you can make an informed decision without doing the math by hand.
What formula does the Bits Calculator use?
The Bits Calculator applies the standard formula: bits = value × unit factor; 1 byte = 8 bits; KB/MB/GB use ×1,000 steps, KiB/MiB/GiB use ×1,024 steps. The tool walks through each step of the calculation so you can verify the numbers yourself.
Is the Bits Calculator free and private?
Yes — the Bits Calculator. There is no sign-up, no paywall, no trial, and no limit on how many calculations you can run. CalcaTools covers its costs with non-intrusive display advertising, so the calculator itself never asks for payment or restricts any feature.
How accurate is the Bits Calculator?
The Bits Calculator applies the standard formula: bits = value × unit factor; 1 byte = 8 bits; KB/MB/GB use ×1,000 steps, KiB/MiB/GiB use ×1,024 steps. It is tested against published worked examples before launch and uses native double-precision arithmetic, so results are accurate to typical precision for the values you enter — with no intermediate rounding that could distort the answer.

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