GB 和 GiB 的区别

GB 和 GiB 的区别

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Gibibyte (GiB) is one of the standard units used in the field of data processing and data transmission (along with mebibyte (MiB), kibibyte (KiB), etc.). Gibibyte, mebibyte, and kibibyte are defined as powers of 2.

1 GiB equals 2³⁰ bytes or 1,073,741,824 bytes. Gibibyte is closely related to gigabyte (GB), which can be a synonym of gibibyte or can refer to 10⁹ bytes or 1,000,000,000 bytes in accordance with International System of Units (SI).

Gigabyte (GB) can have different meanings in different contexts. When referring to computer memory, gigabyte is allways a “power of two” - 1,073,741,824 bytes, but when measuring hard drive capacity it is often defined as 1,000,000,000 bytes. Generally, operating systems calculate disk and file sizes using binary numbers, so a new 500 GB drive you've just purchased would be reported by the OS as "465.66 GB" (meaning 465.66 GiB).

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=============== TB GB  MB KB =================

1 TB = 10¹² bytes = 1000 x 1000 x 1000 x 1000 bytes

1 GB = 10⁹ bytes = 1000 x 1000 x 1000 bytes

1 MB = 10⁶ bytes = 1000 x 1000 bytes

1 KB = 10³ bytes = 1000  bytes

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=============== TiB GiB  MiB KiB ===============

1 TiB = 2⁴⁰ bytes = 1024 x 1024 x 1024 x 1024 bytes

1 GiB = 2³⁰ bytes = 1024 x 1024 x 1024 bytes

1 MiB = 2²⁰ bytes = 1024 x 1024 bytes

1 KiB = 2¹⁰ bytes = 1024  bytes

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1 GiB = 1.073741824 GB

465.66 GiB ≈ 500 GB

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总结

GB 是 十进制 的，GiB 才是 二进制 的。

但是现在经常在写法上，习惯用 GB 代替 GiB，导致有些应用场景下，会产生概念上的混淆。

就会导致一个商业误导，商家宣称一个 500 GB 的硬盘，其实只有 465 GB（其实这里的单位应该是GiB） 左右。

有兴趣深入了解的，可以参考如下资料：

https://www.wintelguy.com/gb2gib.html