File Size Converter

Convert file sizes between all units (Bits, Bytes, KB, MB, GB, TB, PB) with binary (1024) and decimal (1000) standards. Includes visual size comparisons and instant all-unit conversion.

Free to useNo sign-up requiredUpdated Jan 2026

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About File Size Converter

The File Size Converter instantly converts file storage sizes between all common units including Bits, Bytes, Kilobytes (KB), Megabytes (MB), Gigabytes (GB), Terabytes (TB), and beyond. This tool supports both Binary (1024-based, IEC) and Decimal (1000-based, SI) standards, helping you understand why your hard drive shows less space than advertised and making accurate conversions for computing, storage, and networking applications.

Understanding File Size Units

File sizes are measured in units based on bytes. Each byte contains 8 bits and represents a single character or small piece of data. Larger units are multiples of bytes, but there are two different standards for these multiples:

Binary vs Decimal Standards

Binary (1024-based)

Used by operating systems
Based on powers of 2
1 KiB = 1,024 bytes
1 MiB = 1,048,576 bytes
IEC standard (KiB, MiB, GiB)

Decimal (1000-based)

Used by storage manufacturers
Based on powers of 10
1 KB = 1,000 bytes
1 MB = 1,000,000 bytes
SI standard (KB, MB, GB)

File Size Unit Reference Table

Unit	Abbreviation	Binary (Bytes)	Decimal (Bytes)
Bit	b	1/8	1/8
Byte	B	1	1
Kilobyte	KB / KiB	1,024	1,000
Megabyte	MB / MiB	1,048,576	1,000,000
Gigabyte	GB / GiB	1,073,741,824	1,000,000,000
Terabyte	TB / TiB	1,099,511,627,776	1,000,000,000,000
Petabyte	PB / PiB	~1.125 quadrillion	1 quadrillion
Exabyte	EB / EiB	~1.152 quintillion	1 quintillion

How to Use the File Size Converter

Enter a value: Type the file size number you want to convert in the input field. Use the quick presets for common file sizes.
Select the source unit: Choose the unit of your input value (Bits, Bytes, KB, MB, GB, TB, PB, or EB).
Choose the standard: Select Binary (1024) for OS/computing or Decimal (1000) for storage/networking.
Click Convert: View all conversions instantly. Click any result to copy it to your clipboard.

Why Does My Hard Drive Show Less Space?

This is one of the most common questions about file sizes. When you buy a "500 GB" hard drive, it contains 500,000,000,000 bytes (decimal). However, your operating system displays sizes in binary, so it shows approximately 465 GiB. This 7% difference becomes more noticeable with larger drives - a "1 TB" drive shows as about 931 GiB.

Common File Size Reference

Plain text email: 1-5 KB
Word document (1 page): 20-30 KB
MP3 song (3 minutes): 3-4 MB
Smartphone photo: 2-5 MB
DSLR photo (RAW): 20-50 MB
HD video (1 hour, 1080p): 3-5 GB
4K video (1 hour): 15-25 GB
Modern video game: 50-150 GB

Bits vs Bytes in Internet Speed

Internet speeds are usually measured in bits (Mbps - megabits per second), while file sizes are in bytes. To convert your download speed to file transfer rate, divide by 8. A 100 Mbps connection downloads at approximately 12.5 MB/s maximum speed.

Frequently Asked Questions

What is the difference between KB and KiB?

KB (Kilobyte) uses the decimal standard where 1 KB = 1,000 bytes. KiB (Kibibyte) uses the binary standard where 1 KiB = 1,024 bytes. Storage manufacturers typically use decimal (KB, MB, GB) while operating systems often use binary (KiB, MiB, GiB). This difference explains why a "500 GB" hard drive shows as "465 GB" in your computer.

Why does my hard drive show less space than advertised?

Hard drive manufacturers use decimal measurements (1 GB = 1,000,000,000 bytes) while operating systems use binary measurements (1 GiB = 1,073,741,824 bytes). A 1 TB drive (1,000,000,000,000 bytes) displays as approximately 931 GiB in your operating system. This 7% difference increases with larger drives.

How many bytes are in a megabyte?

In decimal (SI) standard: 1 MB = 1,000,000 bytes (used by storage manufacturers). In binary (IEC) standard: 1 MiB = 1,048,576 bytes (used by operating systems). Most people casually use "megabyte" to mean either, but for precise conversions, knowing which standard matters.

What is the largest file size unit?

Common large units include Exabytes (EB), Zettabytes (ZB), and Yottabytes (YB). 1 Exabyte = 1,000 Petabytes = 1 billion Gigabytes. As of 2024, global internet traffic is measured in Exabytes per month, and total world data is estimated at around 120 Zettabytes.

How do I convert bits to bytes?

Divide by 8. There are 8 bits in 1 byte. For example, 100 Mbps (megabits per second) internet equals 12.5 MB/s (megabytes per second) download speed. This is why your 100 Mbps connection downloads at around 12.5 MB per second maximum.

Additional Resources

Reference this content, page, or tool as:

"File Size Converter" at https://MiniWebtool.com/file-size-converter/ from MiniWebtool, https://MiniWebtool.com/

by miniwebtool team. Updated: Jan 27, 2026

Developer API available: Run this tool from your app, automation, or agent with one JSON HTTP request. View API docs