Kbps to Tbps

1 kilobit per second equals 1×10⁻⁹ terabits per second exactly.

1 kilobit per second = 1×10⁻⁹ terabits per second

How to convert kilobits per second to terabits per second

To convert kilobits per second to terabits per second, multiply the number of kilobits per second by 1×10⁻⁹. This factor is exact. To go the other way, multiply terabits per second by 1,000,000,000.

terabits per second = kilobits per second × 1×10⁻⁹

Example: 10 kilobits per second = 1×10⁻⁸ terabits per second.

Network speeds are quoted in bits per second (lowercase b), while file sizes use bytes (uppercase B). Divide Mbps by 8 for MB/s.

About these units

Kilobit Per Second (kbps)

ComputingCurrent unit

1,000 bits per second. Used for voice calls and low-rate links.

Kilobit rates belong to the age of telephone wires. In 1962 AT&T introduced the Bell 103A, a full-duplex modem that sent 300 bit/s over ordinary phone lines, and by 1976 the Bell 212A had reached 1,200 bit/s. Speeds then climbed in steps through the 1990s, until the V.90 standard approved in 1998 offered 56 kbit/s downstream, with 33.6 kbit/s going the other way. That ceiling defined the dial-up era for many home users.

A kilobit per second is 1,000 bit/s, using the standard SI meaning of kilo, and it is still the natural unit for anything lightweight. A digital voice channel using PCM takes 64 kbit/s. MP3 files are often encoded at 128 kbit/s as a mid-range setting, with 320 kbit/s the highest the format supports. Divide by eight to get bytes: 8 kbit/s is 1 kB/s, so a 56 kbit/s modem moves about 7 kB/s, and fetching a 1 MB file over it would take roughly two and a half minutes.

1 kilobit per second = 1,000 bits per second (exactly).

Sources: Wikipedia: Modem (Bell 103, 212A, V.90 history); Wikipedia: Bit rate (voice and MP3 rates); Wikipedia: Kilobit

Terabit Per Second (Tbps)

ComputingCurrent unit

10¹² bits per second. The scale of backbone and undersea cables.

Terabit speeds appear where many signals are combined. A single optical fiber can carry dozens of wavelengths at once through dense wavelength-division multiplexing, and modern undersea cables bundle many fiber pairs, so a typical cable can carry tens of terabits per second overseas. A satellite, by comparison, typically offers about 1 Gbit/s, a ratio of more than 1,000 to 1.

One terabit per second is 10¹² bit/s, or 125 GB/s. At that rate a 25 GB Blu-ray disc worth of data would cross the link in a fifth of a second. Ethernet is moving into this range as well. IEEE approved 800 Gigabit Ethernet in February 2024 under 802.3df, and a separate project, 802.3dj, was started in November 2022 to cover 1.6 Tbit/s. Ordinary users rarely meet the unit directly, since it describes capacity shared among many people.

1 terabit per second = 1,000,000,000,000 bits per second (exactly).

Sources: Wikipedia: Submarine communications cable; Wikipedia: Terabit Ethernet; NIST: Metric (SI) prefixes

Related conversions

See all data transfer rate units.