Convert Terabytes (TB) to Gigabytes (GB)

The formula for TB to GB

In binary units, 1 TB equals 1024 GB, so you multiply the TB value by 1024 to get GB. For example, 2 TB is 2 × 1024 = 2048 GB, and 4 TB is 4 × 1024 = 4096 GB. Decimals work the same, so 0.5 TB becomes 0.5 × 1024 = 512 GB. The 1024 constant comes from computers counting in powers of two (2^10), not a round 1000. That's why 1 TB is exactly 1024 GB rather than 1000 GB.

When you actually need this

You use it to unpack a drive's TB label into GB, the unit you actually manage files in. Asking 'how many 4K videos at roughly 50 GB each fit on a 2 TB NAS?' needs the GB conversion. When a cloud plan is quoted in TB but individual backup folders are in GB, this helps you track remaining space. Estimating data-center or server capacity often means splitting a TB contract into GB allocations. When games install in GB but your SSD is sized in TB, converting shows how many will fit.

Reference points and a common gotcha

Memorizing 1 TB = 1024 GB, 2 TB = 2048 GB, and 4 TB = 4096 GB covers most cases. The gotcha is that drive marketing uses decimal, treating 1 TB as 1000 GB. So a maker's '4 TB' is close to 4000 GB, but your computer counts in binary and shows about 3725 GB, making it look smaller. This isn't a fault, just a difference in counting standards. To match what your computer actually displays, use the 1024-based math this calculator does.

Frequently asked questions

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