How many bytes are in a TB?

1,000,000,000,000 in the decimal terabyte a drive is sold in, and 1,099,511,627,776 in the binary one, the tebibyte (TiB), which is 2 to the 40th power. The difference is 99,511,627,776 bytes, about 92.7 GiB, which is why the disagreement that is invisible at kilobyte scale is impossible to miss on a drive. Both units are in the menus and both appear in the list under any answer.

Why does my 4 TB drive show up as about 3.63 TB?

An exact decimal 4 TB is 4,000,000,000,000 bytes, or 3.63797880709 TiB (about 3.64 TiB when rounded to two decimal places). Software that labels binary TiB as TB can show a smaller numeric count. Actual usable capacity can also differ because of formatting or reserved space, so a displayed 3.63 cannot be attributed to units alone without the actual byte count. For exact stated quantities, 8 TB is 7.27595761418 TiB, 12 TB is 10.9139364213 TiB and 20 TB is 18.1898940355 TiB.

What is the formula for bytes to TB?

TiB = bytes / 1,099,511,627,776 for the binary reading, which is the one this page opens with, and TB = bytes / 1,000,000,000,000 for the decimal one. Reversed, bytes = TiB x 1,099,511,627,776 and bytes = TB x 1,000,000,000,000. You do not have to pick before you look, because whichever you put in the To menu, the other is printed in the list underneath.

Why does 1 TiB come back as 1,099,511,627,780 bytes?

Because the display rounds to twelve significant digits and the exact figure, 1,099,511,627,776, needs thirteen. The last digit shown is rounded up from 76 to 80. It affects what is printed and copied, not what is computed: type the exact 1,099,511,627,776 bytes into the From box and the headline comes back as a clean 1 TiB. For an exact byte count of a tebibyte multiple, use the power of two rather than the printed figure.

Is a terabyte 1,000 GB or 1,024 GB?

A decimal terabyte (TB) is exactly 1,000 decimal gigabytes (GB). A binary tebibyte (TiB) is exactly 1,024 gibibytes (GiB); that is a different unit family. For the same byte quantity, 4 TB = 4,000 GB = 3,725.29029846 GiB, and 1,000,000,000,000 bytes displays as 931.322574615 GiB. A TB is not 1,024 decimal GB.

What is 1 byte in TB?

9.09494701773e-13 TiB, or 1e-12 TB in decimal. Figures below a millionth are printed in exponential form rather than as a row of zeroes, which at this unit begins early: 1,000,000,000 bytes is 0.000909494701773 TiB and is still written out, while a single byte is not. If a readable number is what you need, choose a smaller unit in the To menu, since the same byte is a clean 0.0009765625 KiB.

How do I add up several drives in terabytes?

This page accepts one scalar value. Add exact byte counts yourself, then enter the total to avoid accumulating rounding from printed results. Three stated 4 TB quantities total 12,000,000,000,000 bytes, which displays as 10.9139364213 TiB and exactly 12 TB: the two counts represent the same bytes. This arithmetic does not determine usable capacity or a RAID/storage layout.

Can I convert TB back to bytes here?

Yes. The swap button between the boxes reverses the pair into tebibytes to bytes, where 4 TiB reads 4,398,046,511,100 and 16 TiB reads 17,592,186,044,400, both printed at twelve significant digits. Pick Terabyte (TB) in the From menu after swapping to work in decimal instead, where 1 TB is exactly 1,000,000,000,000 bytes and no rounding is involved.

Why does the page open on bytes and tebibytes when I last converted something else?

This focused page opens on Byte and Tebibyte, while preserving the main converter’s saved unit pair. When browser storage is usable, a saved value and uncommon-unit preference can travel between pages. The value’s suffix must still match the current From unit. Valid deliberate scalar edits can save those fields after a short delay; invalid or incomplete drafts do not overwrite the saved record. Unusable or conflicting records are kept with an explanation until you use Forget saved settings, which keeps the current conversion on screen.

Does anything I type leave the browser?

Your input and converted values are calculated in the browser and are not uploaded by the converter. The definitions arrive with the page, so conversion needs no external data lookup and keeps working offline after the page has loaded. The core conversion needs no account.

Bytes to TB Converter

For equal numeric counts, a binary tebibyte has about 9.95 percent more bytes than a decimal terabyte, so bytes to TB has two answers and this page shows both. It opens with Byte in the From box and Tebibyte (TiB) in the To box, the binary terabyte of 1,099,511,627,776 bytes which some software labels TB, ahead of whatever pair the converter last remembered. Type an exact stated 4 TB quantity, 4,000,000,000,000 bytes, and the headline reads 3.63797880709 TiB, the same byte quantity in binary units: the decimal terabyte of 1,000,000,000,000 bytes sits in the list right below it at exactly 4 TB, along with 4,000 GB, 3,725.29029846 GiB and 3,814,697.26563 MiB. The gap is 99,511,627,776 bytes per terabyte, so a decimal TB is 0.909494701773 TiB and a tebibyte is 9.95 percent more bytes than a terabyte. One display limit is worth knowing at this size: answers print to twelve significant digits, and 1,099,511,627,776 has thirteen, so swapping the boxes and asking for 1 TiB in bytes gives 1,099,511,627,780. The value used in the arithmetic is the exact one; only the printed digits stop at twelve.

From

To9.09494701773e-13

Category: Digital storage

Base unit: byte

kB, MB, GB and TB use powers of 1,000; KiB, MiB, GiB and TiB use powers of 1,024. One byte is eight bits; labels used by other software may differ.

Results round to 12 significant digits using the listed unit definitions. Input must have a finite numeric magnitude and at most 512 significant digits. Type a single decimal or scientific number; a matching From unit suffix is accepted. Commas and grouped spaces separate thousands; decimal commas, fractions and compound measurements are refused.

1 B in every digital storage unit

Bitbit
8
KilobytekB
0.001
MegabyteMB
0.000001
GigabyteGB
1e-9
TerabyteTB
1e-12
KibibyteKiB
0.0009765625
MebibyteMiB
9.53674316406e-7
GibibyteGiB
9.31322574615e-10
TebibyteTiB
9.09494701773e-13

Selectable complete conversion

Unit Converter — Digital storage
Input: 1 (Byte, B)
Result: 9.09494701773e-13 TiB (Tebibyte)
Displayed values round to 12 significant digits.
kB, MB, GB and TB use powers of 1,000; KiB, MiB, GiB and TiB use powers of 1,024. One byte is eight bits; labels used by other software may differ.
All other units:
Bit (bit): 8
Kilobyte (kB): 0.001
Megabyte (MB): 0.000001
Gigabyte (GB): 1e-9
Terabyte (TB): 1e-12
Kibibyte (KiB): 0.0009765625
Mebibyte (MiB): 9.53674316406e-7
Gibibyte (GiB): 9.31322574615e-10
Tebibyte (TiB): 9.09494701773e-13

Common questions

How many bytes are in a TB?: 1,000,000,000,000 in the decimal terabyte a drive is sold in, and 1,099,511,627,776 in the binary one, the tebibyte (TiB), which is 2 to the 40th power. The difference is 99,511,627,776 bytes, about 92.7 GiB, which is why the disagreement that is invisible at kilobyte scale is impossible to miss on a drive. Both units are in the menus and both appear in the list under any answer.
Why does my 4 TB drive show up as about 3.63 TB?: An exact decimal 4 TB is 4,000,000,000,000 bytes, or 3.63797880709 TiB (about 3.64 TiB when rounded to two decimal places). Software that labels binary TiB as TB can show a smaller numeric count. Actual usable capacity can also differ because of formatting or reserved space, so a displayed 3.63 cannot be attributed to units alone without the actual byte count. For exact stated quantities, 8 TB is 7.27595761418 TiB, 12 TB is 10.9139364213 TiB and 20 TB is 18.1898940355 TiB.
What is the formula for bytes to TB?: TiB = bytes / 1,099,511,627,776 for the binary reading, which is the one this page opens with, and TB = bytes / 1,000,000,000,000 for the decimal one. Reversed, bytes = TiB x 1,099,511,627,776 and bytes = TB x 1,000,000,000,000. You do not have to pick before you look, because whichever you put in the To menu, the other is printed in the list underneath.
Why does 1 TiB come back as 1,099,511,627,780 bytes?: Because the display rounds to twelve significant digits and the exact figure, 1,099,511,627,776, needs thirteen. The last digit shown is rounded up from 76 to 80. It affects what is printed and copied, not what is computed: type the exact 1,099,511,627,776 bytes into the From box and the headline comes back as a clean 1 TiB. For an exact byte count of a tebibyte multiple, use the power of two rather than the printed figure.
Is a terabyte 1,000 GB or 1,024 GB?: A decimal terabyte (TB) is exactly 1,000 decimal gigabytes (GB). A binary tebibyte (TiB) is exactly 1,024 gibibytes (GiB); that is a different unit family. For the same byte quantity, 4 TB = 4,000 GB = 3,725.29029846 GiB, and 1,000,000,000,000 bytes displays as 931.322574615 GiB. A TB is not 1,024 decimal GB.
What is 1 byte in TB?: 9.09494701773e-13 TiB, or 1e-12 TB in decimal. Figures below a millionth are printed in exponential form rather than as a row of zeroes, which at this unit begins early: 1,000,000,000 bytes is 0.000909494701773 TiB and is still written out, while a single byte is not. If a readable number is what you need, choose a smaller unit in the To menu, since the same byte is a clean 0.0009765625 KiB.
How do I add up several drives in terabytes?: This page accepts one scalar value. Add exact byte counts yourself, then enter the total to avoid accumulating rounding from printed results. Three stated 4 TB quantities total 12,000,000,000,000 bytes, which displays as 10.9139364213 TiB and exactly 12 TB: the two counts represent the same bytes. This arithmetic does not determine usable capacity or a RAID/storage layout.
Can I convert TB back to bytes here?: Yes. The swap button between the boxes reverses the pair into tebibytes to bytes, where 4 TiB reads 4,398,046,511,100 and 16 TiB reads 17,592,186,044,400, both printed at twelve significant digits. Pick Terabyte (TB) in the From menu after swapping to work in decimal instead, where 1 TB is exactly 1,000,000,000,000 bytes and no rounding is involved.
Why does the page open on bytes and tebibytes when I last converted something else?: This focused page opens on Byte and Tebibyte, while preserving the main converter’s saved unit pair. When browser storage is usable, a saved value and uncommon-unit preference can travel between pages. The value’s suffix must still match the current From unit. Valid deliberate scalar edits can save those fields after a short delay; invalid or incomplete drafts do not overwrite the saved record. Unusable or conflicting records are kept with an explanation until you use Forget saved settings, which keeps the current conversion on screen.
Does anything I type leave the browser?: Your input and converted values are calculated in the browser and are not uploaded by the converter. The definitions arrive with the page, so conversion needs no external data lookup and keeps working offline after the page has loaded. The core conversion needs no account.

Results round to 12 significant digits using the listed unit conventions. Many factors are exact definitions; psi and parsec use rounded coefficients. Temperature includes scale offsets. Days and weeks are fixed-duration units, and unit conversion does not determine calendar dates, ambient pressure or a software label’s convention.