Tiedostokoot

Tiedostokoot, or file sizes, describe the amount of data a digital file occupies on a storage medium or in memory. They are typically displayed in bytes and larger units such as kilobytes (KB), megabytes (MB), and gigabytes (GB).

Two prefix systems are in use: decimal prefixes where 1 KB equals 1,000 bytes and 1 MB equals 1,000,000 bytes, and binary prefixes where 1 KiB equals 1,024 bytes and 1 MiB equals 1,048,576 bytes. Some software still uses the older KB/MB/GB labels while applying binary multiples, which can cause confusion.

File size depends on content and encoding. Plain text tends to be small, while binary data, high‑resolution media, and uncompressed formats are larger. Encoding schemes (for example UTF-8 versus UTF-16) and metadata also contribute to size. Media files often use compression: JPEG and MP3 reduce size, while PNG uses lossless compression; video uses codecs that lower data rates.

Size considerations impact storage planning, backups, and network transfer. File managers usually show the size of each item, and quotas or transfer estimates are based on total file sizes in a folder or archive. To reduce size, users can compress files, strip unnecessary metadata, choose more efficient formats, or adjust resolution, bitrate, or sampling rates. In practice, understanding file size helps with estimating storage needs, download times, and bandwidth usage.