File Size Converter – Convert Bytes KB MB GB TB Free Online

File Size Converter - Convert Bytes KB MB GB TB Free Online | MIFTU

💾 File Size Converter

Convert between Bytes, KB, MB, GB, TB, PB instantly!

✨ Free • Binary (1024) • Decimal (1000) • Real-Time • Accurate

💾 Complete File Size Converter Guide

What is a File Size Converter?

A file size converter is an essential tool that converts digital storage units between different measurements like Bytes, Kilobytes (KB), Megabytes (MB), Gigabytes (GB), Terabytes (TB), and Petabytes (PB). Understanding file sizes is crucial for storage management, file transfers, bandwidth calculations, and system specifications. The converter handles two different measurement systems: Binary (base-1024) used by operating systems and Decimal (base-1000) used by storage manufacturers.

Binary vs Decimal Systems Explained

Binary System (Base-1024) - Computer Science Standard:

  • 1 KB (Kibibyte/KiB) = 1,024 Bytes
  • 1 MB (Mebibyte/MiB) = 1,024 KB = 1,048,576 Bytes
  • 1 GB (Gibibyte/GiB) = 1,024 MB = 1,073,741,824 Bytes
  • 1 TB (Tebibyte/TiB) = 1,024 GB = 1,099,511,627,776 Bytes
  • 1 PB (Pebibyte/PiB) = 1,024 TB = 1,125,899,906,842,624 Bytes
Binary Example (1024-based):
1 GB = 1,024 MB
1,024 MB = 1,024 × 1,024 KB = 1,048,576 KB
1,048,576 KB = 1,048,576 × 1,024 Bytes = 1,073,741,824 Bytes

Why Binary (1024)?

  • Power of 2: Computers use binary (base-2) internally, so 2^10 = 1,024
  • Memory Architecture: RAM is addressed in powers of 2 for efficiency
  • Operating Systems: Windows, macOS, Linux use 1024-based calculations
  • Technical Accuracy: Reflects how computers actually store data
  • Historical Standard: Used since the beginning of computing

Decimal System (Base-1000) - SI Standard:

  • 1 KB (Kilobyte) = 1,000 Bytes
  • 1 MB (Megabyte) = 1,000 KB = 1,000,000 Bytes
  • 1 GB (Gigabyte) = 1,000 MB = 1,000,000,000 Bytes
  • 1 TB (Terabyte) = 1,000 GB = 1,000,000,000,000 Bytes
  • 1 PB (Petabyte) = 1,000 TB = 1,000,000,000,000,000 Bytes
Decimal Example (1000-based):
1 GB = 1,000 MB
1,000 MB = 1,000 × 1,000 KB = 1,000,000 KB
1,000,000 KB = 1,000,000 × 1,000 Bytes = 1,000,000,000 Bytes

Why Decimal (1000)?

  • SI Standard: Follows International System of Units (kilometer, kilogram, etc.)
  • Marketing: Storage manufacturers use 1000 to advertise larger capacities
  • Easier Math: Simpler calculations (1000 vs 1024)
  • Universal Consistency: Matches metric prefixes (kilo, mega, giga)
  • Modern Trend: Increasingly adopted for standardization

Why Your Hard Drive Looks Smaller Than Advertised

⚠️ The Storage Paradox
You buy a "1 TB" hard drive, but Windows shows only 931 GB. Are you being scammed? No—it's the binary vs decimal difference!

The Math Behind It:

  • Advertised: 1 TB = 1,000,000,000,000 Bytes (decimal)
  • Windows Calculates: 1,000,000,000,000 ÷ 1024 ÷ 1024 ÷ 1024 = 931.32 GB (binary)
  • Difference: ~7% "missing" capacity (it's not actually missing!)
  • Legal: Both measurements are correct, just different standards
Real-World Example:
You buy: 500 GB External Hard Drive (decimal)
Manufacturer: 500 × 1,000,000,000 = 500,000,000,000 Bytes
Windows shows: 500,000,000,000 ÷ 1,073,741,824 = 465.66 GB (binary)
Result: Windows shows 465.66 GB, not 500 GB
Both are correct! Just different measurement systems.

Complete Conversion Tables

Binary System (1024-based) - What Your OS Uses:

Unit Abbreviation In Bytes Calculation
Byte B 1 Base unit
Kilobyte KB 1,024 2^10
Megabyte MB 1,048,576 2^20 (1,024²)
Gigabyte GB 1,073,741,824 2^30 (1,024³)
Terabyte TB 1,099,511,627,776 2^40 (1,024⁴)
Petabyte PB 1,125,899,906,842,624 2^50 (1,024⁵)

Decimal System (1000-based) - What Manufacturers Use:

Unit Abbreviation In Bytes Calculation
Byte B 1 Base unit
Kilobyte KB 1,000 10^3
Megabyte MB 1,000,000 10^6 (1,000²)
Gigabyte GB 1,000,000,000 10^9 (1,000³)
Terabyte TB 1,000,000,000,000 10^12 (1,000⁴)
Petabyte PB 1,000,000,000,000,000 10^15 (1,000⁵)

IEC Standard Naming (KiB, MiB, GiB)

To resolve the binary vs decimal confusion, the International Electrotechnical Commission (IEC) introduced new names for binary units:

Binary Unit IEC Name Symbol Value (Bytes)
Kilobyte (binary) Kibibyte KiB 1,024
Megabyte (binary) Mebibyte MiB 1,048,576
Gigabyte (binary) Gibibyte GiB 1,073,741,824
Terabyte (binary) Tebibyte TiB 1,099,511,627,776
Petabyte (binary) Pebibyte PiB 1,125,899,906,842,624

IEC Standard Adoption:

  • Linux: Some distributions use KiB, MiB, GiB
  • macOS: Switched to decimal (GB = 1,000 MB) in recent versions
  • Windows: Still uses binary but labels it as KB, MB, GB (not KiB, MiB, GiB)
  • Technical Documentation: Increasingly using IEC standard for clarity

Common File Sizes Reference

Item Typical Size In Different Units
Text Character (ASCII) 1 Byte 8 bits
Email (text only) 5-50 KB 5,000-50,000 Bytes
Word Document (10 pages) 50-200 KB 0.05-0.2 MB
High-Quality Photo 2-10 MB 2,000-10,000 KB
MP3 Song (3 minutes) 3-5 MB 3,000-5,000 KB
FLAC Song (3 minutes) 25-35 MB 0.025-0.035 GB
HD Video (1 hour) 2-4 GB 2,000-4,000 MB
4K Video (1 hour) 8-15 GB 8,000-15,000 MB
DVD Movie 4.7 GB 4,700 MB
Blu-ray Movie 25-50 GB 0.025-0.05 TB
PC Game (Modern) 50-150 GB 50,000-150,000 MB
Operating System 20-30 GB 20,000-30,000 MB

Data Transfer Speed vs File Size

Understanding how long it takes to transfer files at different speeds:

Connection Speed 1 GB Transfer Time 10 GB Transfer Time
USB 2.0 480 Mbps (60 MB/s) 17 seconds 2.8 minutes
USB 3.0 5 Gbps (625 MB/s) 1.6 seconds 16 seconds
USB 3.1/3.2 10 Gbps (1.25 GB/s) 0.8 seconds 8 seconds
Gigabit Ethernet 1 Gbps (125 MB/s) 8 seconds 1.3 minutes
WiFi 6 (802.11ax) 9.6 Gbps (1.2 GB/s) 0.8 seconds 8.3 seconds
SATA SSD 6 Gbps (600 MB/s) 1.7 seconds 17 seconds
NVMe SSD 32 Gbps (4 GB/s) 0.25 seconds 2.5 seconds
Internet (100 Mbps) 100 Mbps (12.5 MB/s) 1.4 minutes 13.7 minutes
Internet (1 Gbps Fiber) 1 Gbps (125 MB/s) 8 seconds 1.3 minutes

Storage Capacity Examples

What Can You Store?
16 GB USB Drive (binary):
- 4,000 high-quality photos (4 MB each)
- 3,200 MP3 songs (5 MB each)
- 4 HD movies (4 GB each)
- 8,000 Word documents (2 MB each)

1 TB External Hard Drive (binary):
- 250,000 photos
- 200,000 MP3 songs
- 250 HD movies
- 20 modern PC games (50 GB each)

256 GB iPhone Storage:
- 64,000 photos
- 51,200 songs
- 64 HD movies
- 100+ apps + system files

Conversion Formulas

Binary System (1024):

  • Bytes to KB: Divide by 1,024
  • KB to MB: Divide by 1,024
  • MB to GB: Divide by 1,024
  • GB to TB: Divide by 1,024
  • TB to PB: Divide by 1,024
Binary Conversion Example:
Convert 5,242,880 Bytes to MB:
5,242,880 ÷ 1,024 = 5,120 KB
5,120 ÷ 1,024 = 5 MB

Or directly: 5,242,880 ÷ (1,024 × 1,024) = 5 MB

Decimal System (1000):

  • Bytes to KB: Divide by 1,000
  • KB to MB: Divide by 1,000
  • MB to GB: Divide by 1,000
  • GB to TB: Divide by 1,000
  • TB to PB: Divide by 1,000
Decimal Conversion Example:
Convert 5,000,000 Bytes to MB:
5,000,000 ÷ 1,000 = 5,000 KB
5,000 ÷ 1,000 = 5 MB

Or directly: 5,000,000 ÷ (1,000 × 1,000) = 5 MB

Frequently Asked Questions

Q: Why does my 500 GB hard drive show only 465 GB in Windows?
A: Manufacturers use decimal (1 GB = 1,000,000,000 bytes) while Windows uses binary (1 GB = 1,073,741,824 bytes). Your drive has 500,000,000,000 bytes, which Windows calculates as 465.66 GB. You're not losing storage—it's just different measurement systems. Additionally, some space is used for file system overhead and formatting.

Q: Which system should I use—binary or decimal?
A: Use binary (1024) for: OS calculations, RAM specifications, technical documentation, file system analysis. Use decimal (1000) for: Storage device specifications (matching manufacturer labels), network speeds, international standards. Both are correct—just different contexts!

Q: What's the difference between KB and KiB?
A: KB is ambiguous (could mean 1000 or 1024 bytes). KiB (Kibibyte) specifically means 1024 bytes (binary). The IEC standard created KiB, MiB, GiB to eliminate confusion, but Windows still uses KB, MB, GB for binary values. Context matters!

Q: How many GB is 1 TB?
A: Binary: 1 TB = 1,024 GB = 1,048,576 MB. Decimal: 1 TB = 1,000 GB = 1,000,000 MB. Your operating system (Windows/Mac/Linux) uses binary, so 1 TB = 1,024 GB in your file explorer.

Q: Why do storage manufacturers use decimal instead of binary?
A: Marketing and standards. Decimal makes drives appear larger (1 TB = 1,000 GB sounds better than 931 GB binary equivalent). Also, decimal aligns with SI (International System) standards used globally. It's legal and complies with international measurement standards.

Q: How do I calculate how many files fit on my drive?
A: Formula: Number of files = (Available storage in bytes) ÷ (File size in bytes). Example: 16 GB USB (binary) = 17,179,869,184 bytes. For 5 MB photos (5,242,880 bytes each): 17,179,869,184 ÷ 5,242,880 = 3,276 photos. Remember to account for file system overhead (~5-10%).

Q: What's bigger—1000 KB or 1 MB?
A: Depends on system! Binary: 1 MB = 1,024 KB, so 1000 KB < 1 MB. Decimal: 1 MB = 1,000 KB, so 1000 KB = 1 MB. In practice (Windows/Mac), 1000 KB is slightly less than 1 MB (1 MB = 1,024 KB).

Q: How much space does 1 million files take?
A: It depends on file size! 1 million 1KB files = ~1 GB. 1 million 1MB photos = ~1 TB. 1 million 100KB documents = ~100 GB. Also consider file system overhead—millions of small files use more space due to cluster allocation.

Q: Can I convert bits to bytes?
A: Yes! 8 bits = 1 byte. Internet speeds are in bits (Mbps = Megabits per second), while file sizes are in bytes (MB = Megabytes). To convert: 100 Mbps ÷ 8 = 12.5 MB/s. So a 100 Mbps connection downloads at ~12.5 MB per second.

Q: What's the largest file size unit?
A: Commonly used: Petabyte (PB). Beyond that: Exabyte (EB, 1024 PB), Zettabyte (ZB, 1024 EB), Yottabyte (YB, 1024 ZB). Google processes ~20 PB daily. Global internet traffic exceeds 1 ZB per year. Most users never encounter files beyond TB.

Fun Facts About File Sizes

  • The entire Library of Congress contains about 20 Terabytes of text data
  • A single human brain stores approximately 2.5 Petabytes of data
  • Facebook stores over 300 Petabytes of user data
  • The first 1 GB hard drive (1980) cost $40,000 and weighed 550 pounds
  • Netflix streams over 1 Exabyte of data per month
  • All words ever spoken by humans equal approximately 5 Exabytes of data
  • The Large Hadron Collider generates 1 Petabyte of data per second during experiments
  • A floppy disk held 1.44 MB—you'd need 694 floppy disks for 1 GB!
  • The term "Byte" was coined in 1956 by Werner Buchholz at IBM
  • Global data creation exceeded 64 Zettabytes in recent years and is growing exponentially