🗄️ GB to TB Converter

What is the GB to TB Converter?

A gigabyte and a terabyte are both units of digital storage, but "how many gigabytes make a terabyte" has two correct answers depending on which counting convention applies. The binary convention, formalized by JEDEC and used internally by most operating systems, treats 1 TB as 1024 GB because computers address memory and storage in powers of two (2 to the 10th power equals 1024). This is the convention behind the exact figures Windows File Explorer and macOS Finder show when you check a drive or folder's properties.

The decimal convention treats 1 TB as exactly 1000 GB, following the standard SI meaning of the prefix "tera" (one trillion bytes total, one thousand times a gigabyte). Hard drive and SSD manufacturers, along with cloud storage providers like Google Drive, Dropbox, and iCloud, use this convention when they advertise a "2 TB" drive or plan. This is precisely why a drive box labeled "2 TB" shows up as roughly 1.82 TB in an operating system that reports sizes in binary. No bytes are missing, the same physical capacity is simply being measured against two different yardsticks.

The IEC introduced the terms tebibyte (TiB) and gibibyte (GiB) specifically to remove this ambiguity, with 1 TiB defined as exactly 1024 GiB. In everyday use almost nobody adopts these terms, so "TB" and "GB" get used loosely for both meanings, and the only way to know which one applies is context: an operating system property panel or RAM spec usually means binary, while a product listing, cloud storage plan, or network bandwidth figure usually means decimal.

The math itself is plain division and multiplication with no rounding shortcuts: terabytes equal gigabytes divided by the chosen divisor (1024 or 1000), and gigabytes equal terabytes multiplied by that same divisor. This matters in practice whenever you are budgeting storage, since at terabyte scale the binary/decimal gap is large enough to change a purchasing decision. A "10 TB" NAS array, for instance, holds only about 9.1 TB once the operating system reports it in binary, and losing sight of that difference is a common source of "my drive is missing space" support tickets.

When to use it

• Checking why a new external drive or SSD advertised as a round number of TB shows a smaller figure once it is plugged in and formatted.
• Sizing a cloud storage plan (photos, video backups, or a shared drive) against how many gigabytes of files you actually need to store.
• Comparing a NAS, server, or data center storage spec sheet in TB against usage or quota figures reported in GB.
• Converting video, virtual machine, or backup archive sizes between GB and TB when planning storage budgets or migrations.

How to use the GB to TB Converter

1. Choose Binary (1 TB = 1024 GB) if you are matching an operating system drive size, or Decimal (1 TB = 1000 GB) if you are matching a manufacturer spec sheet or cloud storage plan.
2. Type a value into the Gigabytes field to see the equivalent in terabytes appear instantly.
3. Or type a value into the Terabytes field to see the equivalent in gigabytes instead, the converter works in both directions from the same fields.
4. Use the Copy button to copy the result line to your clipboard for pasting into a document, ticket, or spreadsheet.

Formula & method

Worked examples

Common GB to TB conversions (binary, 1 TB = 1024 GB)

Same values converted with the decimal standard (1 TB = 1000 GB)

Common mistakes to avoid

• Assuming there is only one correct divisor. Both 1024 and 1000 are legitimate, they just belong to different conventions (binary/JEDEC vs decimal/SI). Using the wrong one when double-checking a drive size against a spec sheet or an operating system will produce a mismatch that looks like a fault but is not.
• Mixing binary and decimal in the same comparison. If a store lists a drive as "4 TB" (decimal, 4000 GB) and your file manager shows it as roughly 3.64 TB (binary), both numbers describe the same physical drive. Convert using the same standard on both sides before concluding capacity is missing.
• Confusing bits with bytes in network or transfer speeds. Network and internet speeds are usually quoted in gigabits per second (Gbps), not gigabytes. A gigabyte is 8 gigabits, so a "1 Gbps" connection transfers at roughly 0.125 GB per second at best, not 1 GB per second.
• Rounding too early in multi-step conversions. When converting GB to TB to PB in sequence, rounding the TB figure first before dividing again compounds small errors. Keep full precision through each step, or convert directly through bytes when exactness matters, such as capacity planning for a server or data center.

Glossary

Gigabyte (GB)

A unit of digital storage equal to 1024 megabytes (binary convention) or 1000 megabytes (decimal convention).

Terabyte (TB)

A unit of digital storage equal to 1024 GB (binary convention) or 1000 GB (decimal convention), roughly a trillion bytes.

Binary (JEDEC) standard

Counts storage in powers of two, so 1 TB = 1024 GB. Used by most operating systems when they report drive and file sizes.

Decimal (SI) standard

Counts storage in powers of ten, so 1 TB = 1000 GB. Used by drive manufacturers and cloud storage providers on spec sheets and pricing pages.

Tebibyte (TiB)

The IEC term that unambiguously means 1024 gibibytes, introduced to separate the binary meaning from TB, though it is rarely used outside technical documentation.

Petabyte (PB)

The next unit up from a terabyte, equal to 1024 TB (binary) or 1000 TB (decimal), commonly seen in data center and cloud storage capacity figures.

Frequently asked questions