The File Size Converter quickly and accurately converts between various data capacity units such as Byte, KB, MB, GB, TB, and PB. Useful for file downloads, storage capacity calculations, and data transfer calculations.
• 1 KB = 1,024 Bytes
• 1 MB = 1,024 KB = 1,048,576 Bytes
• 1 GB = 1,024 MB = 1,073,741,824 Bytes
• 1 TB = 1,024 GB
• 1 PB = 1,024 TB
※ Computers calculate using 1024 as the base (binary).
※ Storage device manufacturers may use 1000 as the base (decimal).
※ This calculator uses the 1024 base (binary).
File sizes use a binary system based on Bytes. 1 KB is 1,024 Bytes, 1 MB is 1,024 KB (1,048,576 Bytes), and 1 GB is 1,024 MB. This is because computers use binary (base-2), where 2^10 = 1,024. However, storage manufacturers often use decimal (1,000 base), causing a 1 TB SSD to display as approximately 931 GB. Understanding this difference prevents confusion in capacity calculations.
KiB, MiB, GiB, TiB are official binary unit notations, distinct from KB, MB, GB, TB. This notation, defined by the IEC (International Electrotechnical Commission), was introduced to prevent confusion. For example, 1 GiB = 1,073,741,824 Bytes, but 1 GB can be 1,000,000,000 or 1,073,741,824 Bytes depending on definition. Windows and macOS use binary, while hard disk manufacturers use decimal, causing the same drive to display differently.
Modern technology has brought PB (Petabyte), EB (Exabyte), ZB (Zettabyte) into actual use. 1 PB = 1,024 TB, storing approximately 500,000 hours of HD video. Google processes tens of PB of data daily, and global internet traffic is measured in ZB. Understanding these large units is essential for cloud storage and big data analysis. 1 EB can store about 11 million 4K movies.
Actual usable storage is less than advertised capacity. File system overhead uses about 5-7% for NTFS and 3-5% for APFS in metadata. Additionally, decimal/binary difference means a 1 TB drive is actually about 931 GiB. In RAID configurations, RAID 1 (mirroring) uses 50%, RAID 5 uses one disk worth, and RAID 6 uses two disks worth of capacity for parity. Cloud backup planning must account for these losses.
Data transfer speed is measured in Mbps (Megabits per second), while file size is in MB (Megabytes). Since 1 Byte = 8 bits, downloading a 100 MB file on 100 Mbps internet theoretically takes 8 seconds. In reality, protocol overhead and network congestion result in 70-90% efficiency, taking 10-11 seconds. CDN (Content Delivery Network) improves transfer speed by serving files from geographically closer servers.
File compression saves storage space and reduces transfer time. ZIP, 7z, RAR are lossless compression perfectly restoring originals, while JPEG and MP3 are lossy compression sacrificing some quality for significant size reduction. gzip and brotli compress web content text by 70-90%. Video codec H.265 provides same quality as H.264 in 50% smaller files. Deduplication stores identical data blocks only once, reducing backup storage by 50-90%.