Convert Gbps to Tbps

Content last reviewed:2026-09-30

1000 Gbps is 1 Tbps, because a terabit holds a thousand gigabits. Enter a speed in gigabits per second and the converter divides it by 1,000: a 400 Gbps port is 0.4 Tbps, and the 725 Gbps peak at LINX Manchester is 0.725 Tbps.

Gigabits/s

Gbps

Terabits/s

Tbps

How many Tbps is 1000 Gbps?

A thousand gigabits per second is exactly 1 Tbps. The prefix giga means a billion and tera a trillion[1], so one terabit holds a thousand gigabits. To convert, divide the speed in Gbps by 1,000: Tbps = Gbps ÷ 1000.

In your head, move the decimal point three places to the left. A 100 Gbps port is 0.1 Tbps, a 400 Gbps port is 0.4 Tbps and 25 Gbps is 0.025 Tbps. Any figure below a thousand gives a result that starts with a zero.

What is a gigabit per second, and what is a terabit per second?

A gigabit per second is a billion bits sent every second, and a terabit per second is a trillion[1]. A bit is the smallest unit of information, a zero or a one, and eight bits make a byte[2]. To see how many bytes a number of bits comes to, use the bits to bytes converter.

Terabits describe carrier backbones, internet exchange points and links between data centres. A single switch port or a home connection is counted in gigabits or megabits, so the same traffic shows up in Gbps in one place and in Tbps in another. One step down, the Gbps to Mbps converter does the maths, and the data transfer rate converter gives the speed in bytes, the way a download window shows it.

Optical transport cards with green connectors and yellow single-mode fibre patch cords — Optical transport cards with labelled fibres. The yellow cords are single-mode fibres, and the cards marked ROADM (a switch that steers individual wavelengths) split one fibre into channels that are counted separately. Photo: Kirill Sh, Unsplash.

How many terabits does an internet exchange handle?

An internet exchange point is a place where many networks connect directly to one another, so traffic between them doesn't take a long detour through other carriers. The London Internet Exchange, LINX, also runs an exchange in Manchester, and in February 2025 it reported a new record peak of 725Gbps there[3]. In terabits, that is 0.725 Tbps.

Figures like this are written in gigabits while an exchange is still below a terabit, and in terabits once it passes one. LINX Manchester would need another 275 Gbps to reach 1 Tbps, just under what three more 100 Gbps ports running flat out would carry.

Gbps to Tbps conversion table

The rows cover speeds from 1 Gbps, the port in a computer, up to 400,000 Gbps. Results are rounded to three decimal places, and to three significant digits for values below 0.1.

Speed in Gbps	The same in Tbps
1 Gbps	0.001 Tbps
2.5 Gbps	0.0025 Tbps
5 Gbps	0.005 Tbps
10 Gbps	0.01 Tbps
25 Gbps	0.025 Tbps
40 Gbps	0.04 Tbps
50 Gbps	0.05 Tbps
100 Gbps	0.1 Tbps
200 Gbps	0.2 Tbps
250 Gbps	0.25 Tbps
400 Gbps	0.4 Tbps
500 Gbps	0.5 Tbps
800 Gbps	0.8 Tbps
1,000 Gbps	1 Tbps
1,600 Gbps	1.6 Tbps
2,000 Gbps	2 Tbps
3,200 Gbps	3.2 Tbps
4,000 Gbps	4 Tbps
6,400 Gbps	6.4 Tbps
8,000 Gbps	8 Tbps
10,000 Gbps	10 Tbps
12,800 Gbps	12.8 Tbps
16,000 Gbps	16 Tbps
25,600 Gbps	25.6 Tbps
32,000 Gbps	32 Tbps
51,200 Gbps	51.2 Tbps
100,000 Gbps	100 Tbps
200,000 Gbps	200 Tbps
352,000 Gbps	352 Tbps
400,000 Gbps	400 Tbps

The 100, 400 and 800 Gbps rows match the port speeds of IEEE 802.3ba, 802.3bs and 802.3df[4]. For the speed in megabits, use the Gbps to Mbps converter.

Which Ethernet rates lead from a gigabit to a terabit?

The Ethernet speeds sit exactly on the stretch from a gigabit to a terabit. Each row gives the IEEE standard number and, for standards already approved, the year of approval.

Ethernet rate	The same in Tbps	IEEE standard and year
1 Gbps	0.001 Tbps	IEEE 802.3z, 1998
10 Gbps	0.01 Tbps	IEEE 802.3ae, 2002
25 Gbps	0.025 Tbps	IEEE 802.3by, 2016
40 Gbps	0.04 Tbps	IEEE 802.3ba, 2010
100 Gbps	0.1 Tbps	IEEE 802.3ba, 2010
200 Gbps	0.2 Tbps	IEEE 802.3bs, 2017
400 Gbps	0.4 Tbps	IEEE 802.3bs, 2017
800 Gbps	0.8 Tbps	IEEE 802.3df, 2024
1,600 Gbps	1.6 Tbps	IEEE 802.3dj project

The order of speeds and the order of years part ways in one place: 40 and 100 Gbit/s arrived together in 802.3ba in June 2010[5], while the slower 25 Gbit/s only came in June 2016[6]. The 1 and 10 Gbit/s speeds come from older standards from 1998 and 2002[7][8], and 200, 400 and 800 Gbit/s from later standards of the terabit family[4].

How many gigabits does a single optical fibre carry?

A single fibre carries many wavelengths at once, and each one is a separate channel with its own speed. The total in each row is the number of channels multiplied by the speed of one channel.

Total in Gbps	What it adds up from	The same in Tbps
100 Gbps	One channel of 100 Gbit/s	0.1 Tbps
400 Gbps	One channel of 400 Gbit/s	0.4 Tbps
4,000 Gbps	40 channels of 100 Gbit/s	4 Tbps
8,000 Gbps	80 channels of 100 Gbit/s	8 Tbps

The channel counts come from typical DWDM systems: forty channels at 100 GHz spacing or eighty at 50 GHz[9].

Which number formats does this converter accept?

The field takes each of these formats and converts it, so you don't need to tidy anything up before pasting. The table shows what the converter does with each one, and the converter itself calculated every result.

What you type	What the converter shows	Note
1000	1 Tbps	We read a bare number as gigabits per second, because that is the label on the field.
1.5	0.0015 Tbps	The point marks the decimal part, so this is one and a half gigabits per second.
1,500	1.5 Tbps	A comma before three digits separates thousands, so we read fifteen hundred gigabits. A hint appears below the field, and if you meant one and a half, type 1.5.
1 000	1 Tbps	The field skips a space between thousands and reads a thousand gigabits per second.
800 Gb/s	0.8 Tbps	We skip the unit pasted with the number, just like Gbps and Gbit/s.
400GE	0.4 Tbps	GE, short for Gigabit Ethernet, appears in switch and port descriptions. We read it as gigabits per second.
725Gbps	0.725 Tbps	This is how LINX wrote its Manchester record. The field takes the number even without a space before the unit.
1.6 Tbps	1.6 Tbps	We turn terabits into gigabits, so the field shows 1600, and a note below the field tells you about the conversion.
100 Mbps	0.0001 Tbps	We turn megabits into gigabits, so the field shows 0.1, and a note below the field tells you about the conversion.
1 GB/s	0.008 Tbps	We turn gigabytes per second into gigabits, so the field shows 8, and a note below the field tells you about the conversion.
1 1/2	0.0015 Tbps	We read the mixed number as one and a half gigabits per second.

How do you convert port speeds to terabits?

Datasheets give port speeds in gigabits, while the capacity of a whole switch is written in terabits. The steps use 12,800 Gbps as the example.

Read the figure from the datasheet
A switch datasheet might say 12,800 Gbit/s. Type the number into the Gigabits/s field or paste it with its unit.
Read the result
The converter shows 12.8 Tbps in the Terabits/s field. The Copy result button puts that number on your clipboard.
Check that the figure is in bits
Port speeds are given in bits and drive performance in bytes. If the figure comes from a drive description, the right tool is the data transfer rate converter.
Convert the other way
The Swap order button opens the Tbps to Gbps converter with the result, so 12.8 Tbps takes you back to 12,800 Gbps in one click.

Convert other units to Terabits/s

Pbps to Tbps

Convert Gigabits/s to other units

Gbps to Mbps

Sources

Metric (SI) Prefixes — National Institute of Standards and Technology
Byte — Wikipedia
LINX Surpasses 700Gbps Traffic Peak in Manchester, Bolstering Local Internet Connectivity — LINX
Terabit Ethernet — Wikipedia
100 Gigabit Ethernet — Wikipedia
25 Gigabit Ethernet — Wikipedia
Gigabit Ethernet — Wikipedia
10 Gigabit Ethernet — Wikipedia
Wavelength-division multiplexing — Wikipedia
Data-rate units — Wikipedia

Every figure in the tables was computed from the unit definitions and checked arithmetically before publication. Historical values and the names of local units come from the sources listed above.

Content last reviewed: September 30, 2026 · written and checked by the Arteon team

Frequently asked questions about Gbps and Tbps

Is 1 Tbps 1000 or 1024 Gbps?

It is 1000 Gbps. The prefixes giga and tera come from the SI and mean a billion and a trillion[1]. The factor 1024 belongs to binary prefixes, which have their own symbols: Gibit/s and Tibit/s[10].

How do you write terabits per second?

You will see Tbps, Tbit/s and Tb/s, and they all mean the same[10]. The lowercase b stands for bit, and ps or /s for second. A capital B means byte, so TB/s is terabytes per second, eight times as many bits.

How many terabits is a 1 Gbps home connection?

A 1 Gbps line is 0.001 Tbps, one thousandth of a terabit. It would take a thousand such lines running at full speed at the same time to make one terabit per second.

Why does the result have so many zeros after the point?

Because a terabit is a thousand times bigger than a gigabit, so any speed below 1000 Gbps gives a result under one. For values below 0.1 the converter shows three significant digits, which is why 2.5 Gbps gives 0.0025 Tbps rather than a rounded 0.003.

Arteon free tool screenshot: Convert Gbps to Tbps

Have a question or a suggestion?

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