According to common standard in electronic industry, 1GB = 1024MB, 1MB = 1024KB and 1KB = 1024byte, meanwhile, if use different format (FAT/FAT32/NTFS/RAW) to format the card, the displayed capacity may reduce a little. Because different format's file system need occupy different initial space. Like 32GB may get 29.2GB available space in NTFS file system, but maybe 29.4GB available space in FAT32, while before format, it may reach 29.5 - 29.8GB.
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128GBytes = 128,000,000,000 Bytes = 125,000,000K Bytes = 122,068M Bytes = 119.20GB Raw Capacity
64GBytes = 64,000,000,000 Bytes = 62,500,000K Bytes = 61,034M Bytes = 59.60GB Raw Capacity
32GBytes = 29.80GB Raw Capacity
16GBytes = 14.90GB Raw Capacity
8GBytes = 7.45GB Raw Capacity
4GBytes = 3.72GB Raw Capacity
SANDIS ULTRA 8GB 16GB 32GB 64GB 128GB |
B) Card Speed
128MB - Class 4-5
2GB: Class 4 speed guaranteed
4GB - 16GB: Class 4- 10 speed guaranteed
32GB - 128GB: Class 6- 10 speed guaranteed