Convert Gigabytes (GB) to Terabytes (TB)

The formula for GB to TB

In binary units, 1 TB equals 1024 GB, so you divide the GB value by 1024 to get TB. For example, 2048 GB is 2048 ÷ 1024 = 2 TB, and 256 GB is 256 ÷ 1024 = 0.25 TB. A value like 500 GB that doesn't divide evenly becomes 500 ÷ 1024 ≈ 0.488 TB. The 1024 constant exists because computers count in powers of two (2^10), not a round 1000. That's why 1000 GB is about 0.977 TB, just short of a full 1 TB.

When you actually need this

It's useful when organizing external drives or a NAS and adding several GB drives into a total measured in TB. As photos and videos pile up into hundreds of GB, converting to TB makes backup planning clearer. When a cloud plan crosses from GB into TB tiers, this helps you compare which is the better deal. Server work and large datasets often report total capacity in TB, which requires the conversion. When a game library or video archive grows into hundreds of GB, reading it in TB shows the overall scale at a glance.

Reference points and a common gotcha

Memorizing 1024 GB = 1 TB, 512 GB = 0.5 TB, and 256 GB = 0.25 TB covers most estimates. The biggest gotcha is that hard-drive makers advertise in decimal, treating 1 TB as 1000 GB. So a '1 TB' external drive shows up as roughly 931 GB in your operating system, which counts in binary and makes the drive look like it's missing capacity. This isn't a defect, just a difference in counting standards. To match what your computer actually reports, use the 1024-based math this calculator does.

Frequently asked questions

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