qdr.fnd/qdr.fnd.core/Value/Extensions/LongExt.cs

namespace Quadarax.Foundation.Core.Value.Extensions
{
    public static class LongExt
    {
        public static string ToReadableLengthString(this long owner)
        {
            string[] sizes = { "B", "KB", "MB", "GB", "TB" };
            var order = 0;
            while (owner >= 1024 && order < sizes.Length - 1) {
                order++;
                owner /= 1024;
            }

            return $"{owner:0.##} {sizes[order]}";
        }
    }
}