Flash memory vendors:1MB = 1000KB,1G = 1000MB
Operating system using binary arithmetic:1MB = 1024KB,1GB = 1024MB;
so there are some differences between display capacity and nominal capacity of flash memory product
How to verify the Capacity and Speed of the memory card?
1). Please use quality USB 3.0 card reader to verify all memory card by H2testw on PC. Real memory card should pass H2testw with no error.
2). Please don't use cheap card reader to test Micro SD card, speed of Micro SD card will be reduced by low quality card reader.
3). Micro SD memory card speed is greatly affected by card reader and the capacity you choose , USB port ect. Low quality device will 100% slow down card speed,1MB=1000KB.