THz to Hz Converter
Convert terahertz to hertz instantly. 1 THz = 1000000000000 Hz, worked steps and a full reference table.
How to use it
- Type the value in terahertz — the result updates as you type.
- Use Swap to flip the direction, or change either dropdown to convert between any two units.
- Click the result to copy it. The URL updates too, so you can bookmark or share the exact conversion.
Examples
| 1 THz | 1000000000000 Hz |
| 5 THz | 5000000000000 Hz |
| 10 THz | 10000000000000 Hz |
| 100 THz | 100000000000000 Hz |
One terahertz equals 1.0000e+12 hertzes (Hz). To convert terahertzes to hertzes, multiply by 1.0000e+12; to go back the other way, multiply by 1.0000e-12 instead.
The converter above does it as you type and shows the working underneath, so you can check the arithmetic rather than take the number on trust.
What terahertzes and hertzes actually measure
Terahertz (THz) — A terahertz is a trillion hertz. Infrared and far-infrared spectroscopy.
Hertz (Hz) — The hertz is one cycle per second. Mains supply, audio pitch and refresh rates.
THz to Hz conversion table
The most common values, worked out in advance. Anything not listed can be typed straight into the converter.
| THz | Hz |
|---|---|
| 1 THz | 1.0000e+12 Hz |
| 2 THz | 2.0000e+12 Hz |
| 5 THz | 5.0000e+12 Hz |
| 10 THz | 1.0000e+13 Hz |
| 25 THz | 2.5000e+13 Hz |
| 50 THz | 5.0000e+13 Hz |
| 100 THz | 1.0000e+14 Hz |
How to convert terahertzes to hertzes by hand
Multiply the number of terahertzes by 1.0000e+12.
For example, 25 THz × 1.0000e+12 = 2.5000e+13 Hz.
Going the other way, divide by 1.0000e+12 — or multiply by 1.0000e-12, which is the same thing and easier to do in your head.
Everything runs in your browser
There is no server involved in the calculation. The numbers you type never leave your device, nothing is logged, and the page keeps working with no connection once it has loaded. That is not a marketing line — it is simply how the tool is built, because a calculation like this has no reason to touch a network.
Questions people ask
How many Hz are in 1 THz?
1 THz equals exactly 1000000000000 Hz. Multiply any value in terahertz by 1000000000000 to get hertz.
Is anything uploaded to a server?
No. The whole calculation happens in your browser. Nothing is sent anywhere, and the page keeps working offline once loaded.
Last updated 18 August 2026