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Convert Terahertz to Hertz

1 terahertz is 1,000,000,000,000 Hz. One terahertz is exactly 1000000000000 hertz.

One terahertz is 1000000000000 hertz. To convert terahertz to hertz, multiply by 1000000000000; to go the other way, divide by 1000000000000 or multiply by 1.0000 × 10^-12. The factor is exact rather than rounded: it follows from NIST Special Publication 811. A trillion hertz.

Factor checked against the defining standard · How we check

Hertz
1,000,000,000,000 Hz
Terahertz × 1000000000000
1 * 10000000000001,000,000,000,000 Hz

1 terahertz in every frequency unit

1 terahertz expressed in every frequency unit
UnitValueExact factor
hertz1,000,000,000,000 Hz× 1,000,000,000,000
kilohertz1,000,000,000 kHz× 1,000,000,000
megahertz1,000,000 MHz× 1,000,000
gigahertz1,000 GHz× 1,000
terahertz (as entered)1 THz—
revolutions per minute60,000,000,000,000 rpm× 60,000,000,000,000

Factors are entered by hand from NIST Special Publication 811 rather than derived from a units library, so the ones that terminate are exact rather than rounded.

How do you convert terahertz to hertz? The converter and the working

  1. 1.Take the measurement in terahertz.
  2. 2.Multiply by 1000000000000 — that is how many hertz fit in one terahertz.
  3. 3.To go back the other way, divide by 1000000000000, or multiply by 1.0000 × 10^-12.

Worked example: 25 terahertz to hertz

Formula
THz × 1000000000000 = Hz
Arithmetic
25 × 1000000000000 = 25,000,000,000,000 Hz
Answer
25 THz = 25,000,000,000,000 Hz

The factor is exact, so this figure is exact too — only the display is rounded.

Terahertz to hertz conversion table

Terahertz to hertz conversion table
TerahertzHertz
1 THz1,000,000,000,000 Hz
2 THz2,000,000,000,000 Hz
3 THz3,000,000,000,000 Hz
4 THz4,000,000,000,000 Hz
5 THz5,000,000,000,000 Hz
6 THz6,000,000,000,000 Hz
7 THz7,000,000,000,000 Hz
8 THz8,000,000,000,000 Hz
9 THz9,000,000,000,000 Hz
10 THz10,000,000,000,000 Hz
12 THz12,000,000,000,000 Hz
15 THz15,000,000,000,000 Hz
20 THz20,000,000,000,000 Hz
25 THz25,000,000,000,000 Hz
50 THz50,000,000,000,000 Hz
100 THz100,000,000,000,000 Hz
200 THz200,000,000,000,000 Hz
300 THz300,000,000,000,000 Hz
500 THz500,000,000,000,000 Hz
1000 THz1,000,000,000,000,000 Hz
2000 THz2,000,000,000,000,000 Hz
5000 THz5,000,000,000,000,000 Hz
10000 THz10,000,000,000,000,000 Hz

What is a terahertz?

A trillion hertz. Visible light runs from about 400 THz at the red end to 790 THz at the violet, which is the band a wavelength in nanometers is really describing.

What is a hertz?

One cycle per second. The SI unit is defined as a reciprocal second, which is why it is used for periodic events and never for a rate of something that is not periodic.

How many hertz are in a terahertz?

One terahertz is 1000000000000 hertz, exactly. Going the other way, one hertz is 1.0000 × 10^-12 terahertz. Both figures come from the same defined relation rather than from a measurement, which is why they are the same today as they were in 1959.

Every frequency unit here

The whole group — 6 units with their symbols and the size of each one in hertzs — is on the conversion index, along with every pair it makes. The table above already gives each of them relative to a terahertz.

Source: NIST Special Publication 811 — the hertz, and SI prefixes

Cite this page

APA
Rule Calculator. (2026). Convert Terahertz to hertz. Rule Calculator. https://rulecalculators.com/convert/terahertz-to-hertz
MLA
"Convert Terahertz to hertz." Rule Calculator, August 16, 2026, https://rulecalculators.com/convert/terahertz-to-hertz.
Chicago
Rule Calculator. "Convert Terahertz to hertz." Rule Calculator. Last reviewed August 16, 2026. https://rulecalculators.com/convert/terahertz-to-hertz.

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Questions people actually ask

How many hertz are in a terahertz?
1000000000000. One cycle per second. The SI unit is defined as a reciprocal second, which is why it is used for periodic events and never for a rate of something that is not periodic.
How do I convert hertz back to terahertz?
Divide by 1000000000000, or multiply by 1.0000 × 10^-12 — they are the same operation.

Other frequency conversions

Hertz to terahertz — the same conversion the other way.

Calculators that work in frequency