Kilohertz to hertz: what an AM dial is really showing
What this conversion does
It multiplies by a thousand, turning the compact figures on a broadcast dial back into whole cycles per second. The multiplication is exact, so the hertz value is not an approximation of the kilohertz value — it is the same frequency written out in full. That matters when you need to add or subtract frequencies, because arithmetic on the whole numbers avoids decimal slips.
The medium wave band
The AM broadcast band runs from 530 kHz to 1700 kHz in the Americas, with each station occupying ten kilohertz of space. In hertz that is 530,000 to 1,700,000 with a ten thousand hertz channel width. Both descriptions are correct, and the kilohertz version is used on the dial because the whole band then fits between two readable three-digit numbers.
Kilohertz to hertz conversion table
Frequencies from across the medium wave band with their hertz equivalents, laid out so the pattern of a thousand to one is easy to check.
| Kilohertz (kHz) | Hertz (Hz) |
|---|---|
| 1 | 1000 |
| 10 | 10000 |
| 100 | 100000 |
| 530 | 530000 |
| 1000 | 1000000 |
| 1700 | 1700000 |
Why channel spacing is quoted in kilohertz
A station needs room on either side of its carrier for the audio it carries, and the audio itself extends to about five kilohertz. Two stations ten kilohertz apart therefore sit exactly far enough apart not to overlap. Expressing the spacing in kilohertz keeps the arithmetic of planning a band in small numbers, which is why the convention survived even though receivers display other figures in hertz.
Appending three zeroes is not always the answer
Multiplying by a thousand moves the decimal point three places to the right. For a whole number that looks like adding three zeroes, but a value such as 0.5 kHz becomes 500 Hz, and writing 0.5000 would be wrong by a factor of a thousand.
Frequently asked questions
How many hertz are in a kilohertz?
Exactly one thousand. So 1010 kHz is 1,010,000 Hz, and 1 kHz is 1000 Hz. The kilo prefix is a strict power of ten in the SI system, unlike the kilo used in some computing contexts.
What is 530 kHz in hertz?
530,000 Hz, the bottom of the AM broadcast band in the Americas. At the other end, 1700 kHz is 1,700,000 Hz. The band is continuous between them, with stations every ten kilohertz.
Why do AM stations use kilohertz?
Because the whole band fits into three-digit numbers that way. Listing stations as 530 to 1700 is far easier to read on a dial than 530,000 to 1,700,000, and the channel spacing of ten kilohertz stays a small round number.
Is a frequency of 1000 kHz the same as 1 MHz?
Yes, numerically identical. One thousand kilohertz is one megahertz, so the top of the AM band at 1700 kHz is also 1.7 MHz. Broadcasters keep using kilohertz because the band predates the convention of quoting it in megahertz.
Does the converter accept a decimal in kilohertz?
Yes. A value such as 99.5 kHz is 99,500 Hz. A comma is also accepted as a decimal separator, so a reader in a country that writes 99,5 gets the same answer rather than a frequency a thousand times too large.