💾 Data Storage Converter
By ToolNimba Editorial Team · Updated 2026-06-19
Decimal units (SI)
1 KB = 1000 bytes. Used by drive makers, networks, and most marketing.
Binary units (IEC)
1 KiB = 1024 bytes. How operating systems usually count memory and files.
Type a number in any box and every other unit updates instantly.
This data storage converter turns any digital storage figure into bits, bytes, kilobytes, megabytes, gigabytes, terabytes, and petabytes. Type a number into any field and every other unit updates instantly. It uses decimal (SI) units by default, where 1 KB = 1000 bytes, and also shows binary (IEC) units such as KiB and MiB, where 1 KiB = 1024 bytes, so you can match whichever system your device or software reports.
What is the Data Storage Converter?
Digital storage is measured in bits and bytes. A bit is a single binary digit, a 0 or a 1. Eight bits make one byte, which is the smallest unit that typically stores one character of text. Everything larger is just a multiple of the byte, but there are two competing ways to count those multiples, and that is the source of most confusion when you convert storage units.
The decimal or SI system uses powers of 1000: 1 KB is 1000 bytes, 1 MB is 1000 KB, 1 GB is 1000 MB, and so on. This is what hard drive and SSD manufacturers use, what network speeds are quoted in, and what most marketing material means. The binary or IEC system uses powers of 1024 and proper names ending in "bi": 1 KiB is 1024 bytes, 1 MiB is 1024 KiB, 1 GiB is 1024 MiB. Operating systems such as Windows often display file and memory sizes using 1024 multiples while still labelling them KB, MB, or GB, which is why a 1 TB drive shows as roughly 931 GB in your file manager.
This converter keeps the two systems separate and clearly labelled. The decimal section answers questions like "how many MB are in a GB" using the round 1000-based numbers most people expect, while the binary section gives the exact 1024-based values your computer is really working with. Converting through a single base unit (the byte) keeps every result consistent no matter which box you type into.
When to use it
- Checking how many MB are in a GB when planning a phone or cloud storage plan.
- Working out why a 1 TB drive shows up as about 931 GB in Windows.
- Converting a file size from bytes to KB or MB for a quick sanity check.
- Estimating how many photos or songs fit on a card of a given capacity.
How to use the Data Storage Converter
- Find the unit you already know in the decimal (SI) or binary (IEC) section.
- Type your number into that box.
- Read the converted value from every other unit, updated instantly.
- Use the decimal section for drive and network figures, and the binary section for what your operating system reports.
Formula & method
Worked examples
Convert 2 GB to MB (decimal).
- 1 GB = 1000 MB
- 2 GB = 2 × 1000 MB
Result: 2 GB = 2000 MB
Convert 500,000 bytes to KB (decimal).
- 1 KB = 1000 bytes
- 500,000 ÷ 1000 = 500
Result: 500,000 bytes = 500 KB
See why a 1 TB drive reads as about 931 GB in your OS.
- 1 TB (decimal) = 1,000,000,000,000 bytes
- The OS divides by 1024 three times: 1,000,000,000,000 ÷ 1024³
- 1024³ = 1,073,741,824
- 1,000,000,000,000 ÷ 1,073,741,824 ≈ 931.32
Result: A 1 TB drive shows as about 931.32 GiB (labelled GB) in the OS.
Decimal (SI) versus binary (IEC) units in bytes
| Decimal unit | Bytes | Binary unit | Bytes |
|---|---|---|---|
| 1 KB | 1,000 | 1 KiB | 1,024 |
| 1 MB | 1,000,000 | 1 MiB | 1,048,576 |
| 1 GB | 1,000,000,000 | 1 GiB | 1,073,741,824 |
| 1 TB | 1,000,000,000,000 | 1 TiB | 1,099,511,627,776 |
Common decimal conversions
| From | Equals |
|---|---|
| 1 byte | 8 bits |
| 1 KB | 1000 bytes |
| 1 MB | 1000 KB (1,000,000 bytes) |
| 1 GB | 1000 MB (1,000,000 KB) |
| 1 TB | 1000 GB (1,000,000 MB) |
| 1 PB | 1000 TB (1,000,000 GB) |
Common mistakes to avoid
- Mixing up bits and bytes. A byte is 8 bits. Internet speeds are usually in megabits per second (Mbps) while file sizes are in megabytes (MB). A 100 Mbps connection moves about 12.5 MB per second, not 100 MB, because you divide the bit figure by 8.
- Expecting a 1 TB drive to hold a full 1 TB as the OS counts it. Makers use decimal (1 TB = 1,000,000,000,000 bytes), but Windows divides by 1024 and still writes "GB". The same drive then reads as roughly 931 GB, so no space is missing, it is just counted differently.
- Assuming KB always means 1024 bytes. In decimal (SI) usage 1 KB = 1000 bytes. The 1024-byte unit has its own correct name, the kibibyte (KiB). Picking the wrong base introduces about a 2.4% error per step, which compounds at larger sizes.
Glossary
- Bit
- The smallest unit of digital data, a single binary digit that is either 0 or 1.
- Byte
- A group of 8 bits. The basic unit for measuring file and storage size.
- Decimal (SI) units
- Units based on powers of 1000, such as KB, MB, and GB. Used by storage makers and networks.
- Binary (IEC) units
- Units based on powers of 1024, with names like KiB, MiB, and GiB, used to count exact memory sizes.
- Mbps
- Megabits per second, a measure of data transfer speed. Divide by 8 to get megabytes per second.
Frequently asked questions
How many MB are in a GB?
In decimal (SI) units there are 1000 MB in 1 GB, which is the figure most people and storage makers use. In binary (IEC) units, 1 GiB equals 1024 MiB.
How do I convert bytes to KB?
Divide the number of bytes by 1000 for decimal KB, so 500,000 bytes is 500 KB. If you need the binary kibibyte (KiB) your OS may use, divide by 1024 instead.
How many MB are in a GB on my computer versus on a drive label?
A drive label uses decimal units, so 1 GB = 1000 MB. Many operating systems count in 1024s while still writing "GB", so the same data can appear slightly smaller on screen.
Why does my 1 TB hard drive show as 931 GB?
The maker sells it as 1 TB = 1,000,000,000,000 bytes (decimal). Your OS divides by 1024 three times and still labels it GB, giving about 931 GiB. No space is lost, it is just a different counting system.
What is the difference between a bit and a byte?
A bit is a single 0 or 1, the smallest unit of data. A byte is 8 bits. File sizes are quoted in bytes (KB, MB, GB) while connection speeds are usually quoted in bits (Mbps).
What is the difference between KB and KiB?
KB (kilobyte) in the SI system is 1000 bytes. KiB (kibibyte) in the IEC system is 1024 bytes. The same logic applies to MB versus MiB and GB versus GiB.