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Data Size Converter
Convert bytes, KB, MB, GB, TB and bits.
100% FreeRuns instantlyNo watermark
- 1Enter detailsAdd the numbers for your scenario.
- 2CalculateVootkit updates the result instantly.
- 3ReviewCheck totals, notes and breakdowns.
Private by designProcessed on your device where possible.
Works on any deviceDesktop, tablet and mobile browsers.
No installationOpen the page and start working.
Always free coreUse the free plan for everyday tasks.
How to use Data Size Converter
Vootkit updates the result instantly.
02Check totals, notes and breakdowns.
03Copy the answer into your workflow.
04Your files stay private
Your work is processed locally in your browser where possible and is never added to a Vootkit upload library.
Learn more about privacyA 1 TB drive shows up as about 931 GB in your operating system, and nothing is wrong or missing. Two different definitions of "gigabyte" are in circulation, and the gap between them widens at every step up the scale.
What Data Size Converter does
Converts storage and bandwidth units using binary multiples of 1024 — the convention operating systems use, where a kilobyte is 1024 bytes and a gigabyte is 1,073,741,824.
Also converts bits. This is the other classic confusion: internet speeds are quoted in megabits per second, file sizes in megabytes, and there are 8 bits in a byte — so a 100 Mbps line downloads at about 12.5 MB/s at best.
Exact factors, in bytes
| Kilobyte | 1024 |
|---|---|
| Megabyte | 1,048,576 — that is 1024² |
| Gigabyte | 1,073,741,824 — 1024³ |
| Terabyte | 1,099,511,627,776 — 1024⁴ |
| Bit | 0.125 — eight bits to a byte |
| Megabit | 131,072 |
| Drive manufacturers use | 1000, not 1024 — hence "missing" space |
| 1 TB advertised shows as | About 931 GB in your OS |
Detailed steps
- Enter the amount.
- Choose the units, watching bits against bytes.
- Read the result.
Worth knowing
Divide a megabit figure by 8 to get megabytes. A 100 Mbps connection tops out around 12.5 MB/s, so a 1 GB download takes at least 80 seconds even on a perfect line. Internet providers quote bits because the number is eight times bigger, and it is the single most misread figure in consumer technology.
Frequently Asked Questions
Why does my 1 TB drive show as 931 GB?
Manufacturers count a terabyte as 1,000,000,000,000 bytes; your operating system counts it as 1024⁴, which is about 1.0995 trillion. Dividing one by the other gives roughly 931. Nothing is lost — the two are just using different definitions of the same word.
Which does this tool use, 1000 or 1024?
1024, matching what your operating system reports. If you are checking against a manufacturer’s figure, expect a difference of about 7% at gigabyte scale and 10% at terabyte scale.
What is the difference between Mb and MB?
Capitalisation, and a factor of eight. Mb is megabits, used for connection speeds; MB is megabytes, used for file sizes. A 100 Mb/s line delivers at most about 12.5 MB/s.
What are KiB and MiB?
The unambiguous binary units — kibibyte and mebibyte — defined precisely to end this confusion. They mean 1024 and 1024², exactly what this tool uses for KB and MB. Adoption outside technical documentation has been slow.
Is Data Size Converter free?
Yes. The Vootkit free plan includes 5 tool runs a day. Upgrade to Vootkit Pro for unlimited daily use, an ad-free workspace and saved workflows.
Are my files uploaded?
No. Data Size Converter runs entirely in your browser — your file is processed on your own device and never sent to a server. There is nothing for us to store or delete.
Do I need to install anything?
No. Data Size Converter works in any modern browser on desktop, tablet or phone. Open the page and start.
How often can I use it? Is there a daily limit?
On the free plan you get 5 tool runs a day. When you reach the limit you'll see a prompt to upgrade, and it resets the next day. Vootkit Pro removes the cap entirely for unlimited daily use.
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