Convert oscillator frequency accuracy between parts per million (ppm) and Hz offset for any carrier frequency.
ppm → Hz Offset
Frequency offset (Hz)
Frequency offset (kHz)
Frequency offset (MHz)
Upper frequency limit
Lower frequency limit
Hz Offset → ppm
Accuracy in ppm
Frequently Asked Questions
What does ppm mean in RF?
In RF, ppm (parts per million) is a way to express the frequency accuracy or stability of an oscillator relative to its nominal frequency. A crystal oscillator rated at ±1 ppm means its output frequency will deviate by at most 1 Hz for every 1,000,000 Hz of nominal frequency. For example, a 10 MHz oscillator with ±1 ppm accuracy will produce a signal between 9,999,990 Hz and 10,000,010 Hz.
What is a typical oscillator accuracy for 5G?
5G NR has very tight frequency accuracy requirements. Base stations (gNB) must maintain frequency accuracy within ±0.05 ppm (50 ppb) of their assigned channel frequency. User equipment (UE) requirements are less stringent at ±0.1 ppm. For GNSS-disciplined oscillators used in 5G timing, stabilities of ±20 ppb (0.02 ppm) or better are common. This is in stark contrast to older Wi-Fi or Bluetooth devices that may use ±20–40 ppm crystal oscillators.
Why does frequency accuracy matter in telecom?
Frequency accuracy matters in telecom for several reasons. First, regulatory compliance requires transmitters to stay within a licensed channel bandwidth. Second, OFDM-based systems (LTE, 5G NR, Wi-Fi) are highly sensitive to carrier frequency offset (CFO) — excessive offset causes inter-subcarrier interference and degrades demodulation performance. Third, synchronization between cells in a network (frequency and time synchronization) is critical for features like coordinated multipoint (CoMP) and handover. Fourth, GNSS receivers require tight frequency accuracy to maintain lock on satellite signals.