Data Storage Converter
Convert storage sizes between bits, bytes, KB, MB, GB, TB and beyond using binary units, with clear decimal versus binary guidance.
Data Storage Converter — input your values
What does this conversion calculator do?
The data storage converter works with binary units, where each step is 1,024 times the previous one: 1 KB = 1,024 bytes, 1 MB = 1,048,576 bytes, and so on up to exabytes. It also converts between bits and bytes.
This is the definition used by operating systems when displaying file sizes. Note the well-known confusion: storage vendors often label drives with decimal values (1 MB = 1,000,000 bytes), which is why a 1 TB drive shows as roughly 931 GB on your computer.
If you see SI-style labels such as KiB or MiB, those are the unambiguous binary units; KB and MB in this converter follow the widespread binary convention.
Formula and variables
Binary units: 1 KB = 1,024 B, 1 MB = 1,048,576 B, 1 GB = 1,073,741,824 B. Disk vendors may use decimal values of 1,000 instead.
| Symbol | Meaning |
|---|---|
| factor(from) | How many bytes one 'from' unit equals (power of 1,024) |
| factor(to) | How many bytes one 'to' unit equals (power of 1,024) |
Worked example
Convert 1 gigabyte into megabytes.
- 1 GB = 1,024 MB because each binary step is 1,024.
Answer: 1 GB = 1,024 MB (binary).
Tips and common mistakes
Tips
- As a rule of thumb, divide the labeled drive size by 1.024³ to estimate usable space: a 1 TB drive shows about 931 GB in your operating system.
- Network speeds are quoted in bits per second (Mbps), while downloads are shown in bytes per second (MB/s) — divide Mbps by 8 for MB/s.
- If the label says Ki, Mi, Gi or Ti, it is the strict binary unit; plain K, M, G can be ambiguous between 1,024 and 1,000.
- For approximate mental math, treating 1 GB as 1,000 MB is fine for estimates but wrong by about 2.4%.
Common mistakes to avoid
- Assuming 1 KB = 1,000 bytes when your operating system reports 1,024.
- Mixing up megabits and megabytes — a 100 Mbps connection transfers at most 12.5 MB/s.
- Expecting a drive labeled 1 TB to show 1,000,000,000,000 bytes as 1 TB in Windows — it shows roughly 931 GB because of the binary convention.
Data Storage Converter — frequently asked questions
How many MB are in a GB?
In binary units, 1 GB = 1,024 MB. In decimal terms, 1 GB = 1,000 MB — the source of most storage-size confusion.
Why does a 1 TB drive only show about 931 GB?
Drive makers label capacity in decimal units (1 TB = 1,000,000,000,000 bytes), while operating systems display binary units (1 TB = 1,099,511,627,776 bytes). The difference is the missing 69 GB.
What is the difference between a bit and a byte?
A bit is a single binary digit (0 or 1); a byte is 8 bits. File sizes use bytes, while network speeds use bits per second.
What do KiB, MiB and GiB mean?
They are the unambiguous binary prefixes adopted by the IEC: 1 KiB = 1,024 bytes, 1 MiB = 1,048,576 bytes. Use them when you want to avoid the KB-versus-1,000 ambiguity.
How many bytes are in a megabyte?
In binary convention, 1,048,576 bytes (1,024 × 1,024). In the decimal convention used by some vendors, 1,000,000 bytes.
How do I convert Mbps to MB/s?
Divide by 8. A 100 Mbps connection transfers up to 12.5 MB/s, and an 8 Mbps connection about 1 MB/s.