根据之前所有的答案，以下是我的看法。它是一个以字节为单位以整数形式存储文件大小的对象。但是当你尝试打印对象时，你会自动得到一个人类可读的版本。

class Filesize(object):
    """
    Container for a size in bytes with a human readable representation
    Use it like this::

        >>> size = Filesize(123123123)
        >>> print size
        '117.4 MB'
    """

    chunk = 1024
    units = ['bytes', 'KB', 'MB', 'GB', 'TB', 'PB']
    precisions = [0, 0, 1, 2, 2, 2]

    def __init__(self, size):
        self.size = size

    def __int__(self):
        return self.size

    def __str__(self):
        if self.size == 0: return '0 bytes'
        from math import log
        unit = self.units[min(int(log(self.size, self.chunk)), len(self.units) - 1)]
        return self.format(unit)

    def format(self, unit):
        if unit not in self.units: raise Exception("Not a valid file size unit: %s" % unit)
        if self.size == 1 and unit == 'bytes': return '1 byte'
        exponent = self.units.index(unit)
        quotient = float(self.size) / self.chunk**exponent
        precision = self.precisions[exponent]
        format_string = '{:.%sf} {}' % (precision)
        return format_string.format(quotient, unit)

简单的两行字怎么样:

def humanizeFileSize(filesize):
    p = int(math.floor(math.log(filesize, 2)/10))
    return "%.3f%s" % (filesize/math.pow(1024,p), ['B','KiB','MiB','GiB','TiB','PiB','EiB','ZiB','YiB'][p])

下面是它的工作原理:

计算log2(文件大小) 除以10得到最接近的单位。(例如，如果大小是5000字节，最接近的单位是Kb，所以答案应该是X KiB) 返回file_size/value_of_closest_unit和unit。

然而，如果filesize为0或负(因为log对于0和-ve数字是未定义的)，它就不起作用。你可以为他们添加额外的检查:

def humanizeFileSize(filesize):
    filesize = abs(filesize)
    if (filesize==0):
        return "0 Bytes"
    p = int(math.floor(math.log(filesize, 2)/10))
    return "%0.2f %s" % (filesize/math.pow(1024,p), ['Bytes','KiB','MiB','GiB','TiB','PiB','EiB','ZiB','YiB'][p])

例子:

>>> humanizeFileSize(538244835492574234)
'478.06 PiB'
>>> humanizeFileSize(-924372537)
'881.55 MiB'
>>> humanizeFileSize(0)
'0 Bytes'

—Kb与KiB有区别。KB表示1000字节，而KiB表示1024字节。KB、MB、GB都是1000的倍数，KiB、MiB、GiB等都是1024的倍数。更多信息请点击这里

我喜欢senderle的十进制版本的固定精度，所以这里有一种与上面joctee的答案的混合(你知道你可以取非整数底数的对数吗?):

from math import log
def human_readable_bytes(x):
    # hybrid of https://stackoverflow.com/a/10171475/2595465
    #      with https://stackoverflow.com/a/5414105/2595465
    if x == 0: return '0'
    magnitude = int(log(abs(x),10.24))
    if magnitude > 16:
        format_str = '%iP'
        denominator_mag = 15
    else:
        float_fmt = '%2.1f' if magnitude % 3 == 1 else '%1.2f'
        illion = (magnitude + 1) // 3
        format_str = float_fmt + ['', 'K', 'M', 'G', 'T', 'P'][illion]
    return (format_str % (x * 1.0 / (1024 ** illion))).lstrip('0')

我最近提出了一个避免循环的版本，使用log2来确定大小顺序，作为后缀列表的移位和索引:

from math import log2

_suffixes = ['bytes', 'KiB', 'MiB', 'GiB', 'TiB', 'PiB', 'EiB', 'ZiB', 'YiB']

def file_size(size):
    # determine binary order in steps of size 10 
    # (coerce to int, // still returns a float)
    order = int(log2(size) / 10) if size else 0
    # format file size
    # (.4g results in rounded numbers for exact matches and max 3 decimals, 
    # should never resort to exponent values)
    return '{:.4g} {}'.format(size / (1 << (order * 10)), _suffixes[order])

不过，它的可读性很可能被认为是非python化的。

总有一个这样的人。今天轮到我了。这是一行代码——如果算上函数签名的话是两行。

def human_size(bytes, units=[' bytes','KB','MB','GB','TB', 'PB', 'EB']):
    """ Returns a human readable string representation of bytes """
    return str(bytes) + units[0] if bytes < 1024 else human_size(bytes>>10, units[1:])

>>> human_size(123)
123 bytes
>>> human_size(123456789)
117GB

如果你需要大于1艾字节的大小，那就有点麻烦了:

def human_size(bytes, units=[' bytes','KB','MB','GB','TB', 'PB', 'EB']):
    return str(bytes) + units[0] if bytes < 1024 else human_size(bytes>>10, units[1:]) if units[1:] else f'{bytes>>10}ZB'

def human_readable_data_quantity(quantity, multiple=1024):
    if quantity == 0:
        quantity = +0
    SUFFIXES = ["B"] + [i + {1000: "B", 1024: "iB"}[multiple] for i in "KMGTPEZY"]
    for suffix in SUFFIXES:
        if quantity < multiple or suffix == SUFFIXES[-1]:
            if suffix == SUFFIXES[0]:
                return "%d%s" % (quantity, suffix)
            else:
                return "%.1f%s" % (quantity, suffix)
        else:
            quantity /= multiple