My 64gig SD card thinks its 32gig

Possible short answer: "Try formatting the SD card to restore its full capacity."

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Why Is My 64gig SD Card Only Recognized as 32gig?
If you have recently purchased a 64GB SD card and find that it is only recognized as a 32GB card, it can be frustrating. However, there are a few reasons why this might be happening. In this article, we will go over the most common reasons for this and what you can do about it.

How to Fix a 64gig SD Card That is Showing as 32gig
SD cards are commonly used in portable devices such as cameras, smartphones, and tablets to store photos, videos, and other media files. One common issue with SD cards is that they can sometimes show less storage capacity than what they were advertised for. For example, a 64GB SD card may show as only 32GB of available storage. This can be a frustrating experience for users who rely on SD cards for their data storage needs.

Understanding the Limitations of Your 64gig SD Card: Why It Might Be Reading as 32gig
An SD card with 64 gigabytes (GB) of storage capacity is a popular choice for many devices, such as cameras, smartphones, and tablets. However, users may come across issues where their 64GB SD card is displaying only 32GB of storage capacity. This can be quite frustrating, especially if the user has already filled up the 32GB and cannot access the remaining 32GB of storage. In order to understand why this happens, it's important to know how SD cards work.