Terahertz to hertz (THz to Hz) converter

What is a terahertz to hertz converter?

A terahertz to hertz converter is an online tool that translates a frequency given in terahertz (THz) into its equivalent value in hertz (Hz), and back again. Both units measure the same physical quantity — the number of cycles or oscillations that occur each second — but they live at opposite ends of the scale. The hertz is the base SI unit of frequency, while the terahertz is one of its largest practical multiples, used to describe extremely fast oscillations such as those of infrared and far-infrared light.

Because a single terahertz equals a trillion hertz, working between the two by hand is error prone. The converter removes the guesswork: you type a value into either field, choose the unit, and the matching value appears instantly in the other field.

How it works

Frequency multiples in the SI system are built on powers of ten, which makes the relationship between hertz and its larger units completely regular:

• 1 kilohertz (kHz) = 1,000 Hz
• 1 megahertz (MHz) = 1,000,000 Hz
• 1 gigahertz (GHz) = 1,000,000,000 Hz
• 1 terahertz (THz) = 1,000,000,000,000 Hz

So converting terahertz to hertz means multiplying by one trillion (10^12), and converting hertz back to terahertz means dividing by the same factor. The converter applies this internally, regardless of which intermediate units (kHz, MHz, GHz) you pick on either side.

Formula

To convert terahertz to hertz, multiply by one trillion:

$\text{Hz} = \text{THz} \times 1{,}000{,}000{,}000{,}000$

To convert hertz back to terahertz, divide by the same factor:

$\text{THz} = \text{Hz} \div 1{,}000{,}000{,}000{,}000$

Terahertz to hertz conversion table

The table below lists common terahertz values together with their equivalents in hertz, gigahertz, and megahertz.

Examples

Example 1: 1 THz to hertz

A physicist describes a far-infrared source as oscillating at 1 THz. To express this in the base SI unit, multiply by one trillion:

$1 \text{ THz} \times 1{,}000{,}000{,}000{,}000 = 1{,}000{,}000{,}000{,}000 \text{ Hz}$

So 1 THz equals 1,000,000,000,000 Hz (that is, 10^12 Hz).

Example 2: Hertz back to terahertz

Suppose a signal is logged as 1,000,000,000,000 Hz and you need it in terahertz. Divide by one trillion:

$1{,}000{,}000{,}000{,}000 \text{ Hz} \div 1{,}000{,}000{,}000{,}000 = 1 \text{ THz}$

The 10^12 Hz signal is exactly 1 THz.

Example 3: 2.5 THz to hertz

A spectroscopy line sits at 2.5 THz. Converting to hertz:

$2.5 \text{ THz} \times 1{,}000{,}000{,}000{,}000 = 2{,}500{,}000{,}000{,}000 \text{ Hz}$

That is 2.5 x 10^12 Hz, or 2,500,000,000,000 Hz.

Example 4: 1 THz expressed in gigahertz

Sometimes you do not need all the way down to hertz. Because 1 GHz = 10^9 Hz and 1 THz = 10^12 Hz, one terahertz equals one thousand gigahertz:

$1 \text{ THz} = 1{,}000 \text{ GHz}$

This is handy when comparing terahertz-band sources with microwave or radio equipment rated in gigahertz.

Notes

• The conversion is exact: it is a fixed power of ten, with no rounding involved in the factor itself.
• The terahertz region of the spectrum (roughly 0.1 to 10 THz) sits between microwaves and infrared light and is widely used in imaging, security scanning, and material analysis.
• Hertz is named after the physicist Heinrich Hertz, who demonstrated the existence of electromagnetic waves.
• The converter accepts decimals, so you can enter fractional terahertz values such as 0.3 THz or 2.75 THz.

Frequently asked questions

How many hertz are in 1 terahertz?

One terahertz equals 1,000,000,000,000 hertz, which is one trillion hertz, or 10^12 Hz.

How do I convert terahertz to hertz?

Multiply the number of terahertz by 1,000,000,000,000 (one trillion). For example, 2.5 THz x 10^12 = 2,500,000,000,000 Hz.

How do I convert hertz back to terahertz?

Divide the number of hertz by 1,000,000,000,000. For example, 5,000,000,000,000 Hz ÷ 10^12 = 5 THz.

How many gigahertz are in a terahertz?

There are 1,000 gigahertz in one terahertz, because a terahertz is 10^12 Hz and a gigahertz is 10^9 Hz. If you work mostly in gigahertz, you can use our gigahertz to hertz converter.

What is the terahertz band used for?

Terahertz radiation is used in non-destructive imaging, security body scanners, wireless communication research, and the chemical analysis of materials, because it passes through many non-metallic substances without ionizing them.

Can this converter handle very small terahertz values?

Yes. The tool accepts any decimal input, so values like 0.001 THz (equal to 1,000,000,000 Hz, or 1 GHz) convert accurately.