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Data Size Converter Tool

Enter a value and unit to instantly convert between bits, bytes, KB, MB, GB, TB, and PB. Toggle between decimal (SI) and binary bases.

Last updated: 2026/10/16 Developer Feedback & bug reports
Input
Conversion Results
Bit (bit) -
Byte (B) -
KB -
MB -
GB -
TB -
PB -

How to Use

1

Enter a Value and Unit

Type the number you want to convert and choose its unit (bit, byte, KB, MB, GB, etc.).

2

Choose the Base

Switch between decimal (SI: KB/MB) and binary (KiB/MiB) to change the displayed units and the calculation.

3

View and Copy Results

All units are converted instantly. Use the copy button on each row to copy the value you need.

About Data Size Conversion

This tool converts between data size units such as bits, bytes, kilobytes (KB), megabytes (MB), gigabytes (GB), terabytes (TB), and petabytes (PB). Because storage and network calculations mix SI prefixes (KB = 1000) with binary prefixes (KiB = 1024), both systems are supported. All calculations run entirely in your browser.

Features

  • Real-time ConversionEvery unit is converted instantly as you type.
  • SI / Binary ToggleSwitch between decimal (KB) and binary (KiB) with a single tap.
  • Wide Unit CoverageConverts bit and byte through KB, MB, GB, TB, and PB at once.
  • Privacy ProtectedAll processing happens in your browser. No data is sent to servers.

Use Cases

  • Convert storage capacity and file sizes
  • Check network speed and bandwidth (bps vs Bps)
  • Estimate cloud costs and data transfer volume
  • Compare OS (binary) vs manufacturer (decimal) sizes
  • Calculate buffer sizes in programming

FAQ

What is the difference between KB and KiB?
KB (kilobyte) is an SI prefix where 1 KB = 1000 bytes, while KiB (kibibyte) is a binary prefix where 1 KiB = 1024 bytes. Drive manufacturers usually use decimal (KB), while operating systems often report file sizes in binary (KiB), so the same number can represent different actual capacities. This tool lets you check both by switching the base.
How do bits and bytes differ?
1 byte equals 8 bits. Network speed is usually measured in "bps" (bits per second), while file sizes are measured in bytes, which is a common source of confusion. For example, a 100 Mbps connection corresponds to roughly 12.5 MB (megabytes) per second of download in theory.
Why do the OS and manufacturer show different capacities?
Storage manufacturers label capacity using decimal units (1 GB = 1,000,000,000 bytes), while many operating systems calculate in binary (showing 1 GiB as 1 GB). As a result, a "500 GB" drive is shown as about 465 GB (GiB) by the OS. You can confirm the difference by switching the base.
Can I convert decimals and very large numbers?
Yes. The tool supports decimals such as 0.5 GB as well as petabyte (PB) scale numbers. Extremely large or small values may be shown in exponential notation for readability.
Is my data sent to a server?
No. All conversions run entirely in your browser using JavaScript, and the values you enter are never sent to or stored on any server. You can use the tool with complete peace of mind.

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Related Guides

Data Size Units Explained: KB, MB, GB and the 1000 vs 1024 Difference Learn data size units from the ground up: the relationship between bits and bytes, the meaning of KB, MB, and GB, the difference between SI prefixes (1000) and binary prefixes like KiB and MiB (1024), why storage and OS figures differ, how it differs from bps speed, and rough size references. Network Speed Basics: bps vs Byte/s, Mbps, Real Speed & Download Time Learn network speed basics in plain terms: the difference between bps (bits per second) and Byte/s, how to read Mbps and Gbps, why real-world speed is slower than advertised, and how to estimate download time from a file size in GB.