Gigabytes to Terabytes
Enter gigabytes and read terabytes. In decimal units a terabyte is 1,000 GB; the binary switch on the card uses 1,024 GB, which is how Windows reports large drives.
Formula: TB = GB × 0.001
1,000 GB
in one terabyte (decimal)
Binary reading: 1,024 GB, the way Windows counts.
GB to TB table
| Gigabytes (GB) | Terabytes (TB) |
|---|---|
| 1 | 0.001 |
| 2 | 0.002 |
| 3 | 0.003 |
| 4 | 0.004 |
| 5 | 0.005 |
| 6 | 0.006 |
| 7 | 0.007 |
| 8 | 0.008 |
| 9 | 0.009 |
| 10 | 0.01 |
| Gigabytes (GB) | Terabytes (TB) |
|---|---|
| 12 | 0.012 |
| 15 | 0.015 |
| 20 | 0.02 |
| 25 | 0.025 |
| 30 | 0.03 |
| 40 | 0.04 |
| 50 | 0.05 |
| 60 | 0.06 |
| 75 | 0.075 |
| 100 | 0.1 |
Planning storage in terabytes
Terabytes are the unit for hard drives, NAS boxes and large cloud plans. To size one, add up what you keep in gigabytes and divide by 1,000: a 600 GB photo library plus 250 GB of video and 150 GB of documents is 1,000 GB, so a 1 TB drive is already full. A 2 TB drive leaves room to grow and space for the file system.
Backups need more than the data itself. Versioned backups keep older copies of changed files, and a common rule of thumb is to buy at least twice the capacity you back up.
Sizing a drive
- Add up the sizes your file manager reports
- Check whether it counts in decimal or binary units
- Divide the total by 1,000 for decimal terabytes
- Leave 10 to 20% free so the drive keeps its speed
- Double the result for a backup that keeps old versions
The binary gap at the terabyte scale
Every step up adds another factor of 1,024 against 1,000, so the mismatch gets bigger at each prefix. A binary terabyte, properly called a tebibyte (TiB), holds 1,099,511,627,776 bytes, almost 10% more than the decimal terabyte on the box. The IEC introduced the -bi names in 1998 to end the confusion, though most interfaces still print TB for both.
Moving smaller sizes? GB to MB breaks gigabytes down, and MB to GB builds them back up.
Free space is not the full capacity
Operating systems, recovery partitions and the file system's own tables take a share of every drive. Expect a little less usable space than any conversion shows.
One gigabyte in other units
One gigabyte in every other data size unit on this site
- Bits8,000,000,000 bit
- Bytes1,000,000,000 B
- Kilobytes1,000,000 KB
- Megabytes1,000 MB
- Terabytes0.001 TB
- Megabits8,000 Mbit
GB to TB questions
Is 1,000 GB the same as 1 TB?
Yes, in decimal units, which drive makers and most cloud services use. In the binary reading 1 TB is 1,024 GB, so 1,000 GB comes to about 0.977 TB.
How many terabytes is 500 GB?
500 GB is 0.5 TB in decimal units, or about 0.488 TB in binary units.
Why does a 2 TB drive show about 1.8 TB?
The drive holds 2 trillion bytes. Windows divides by 1,024 four times instead of 1,000, so the same bytes display as about 1.82 TB. Formatting also reserves a small amount for the file system.
How many 4 GB movies fit on 1 TB?
About 250 in decimal units. In practice leave some free space, since a nearly full drive slows down and the file system needs room to work.