Convert Centibels to Millibels

Convert Centibels (cB) to Millibels (mB) instantly and accurately.

Conversion Formula

mB = cB × 10

About Centibels

The centibel (cB) is one-hundredth of a bel (1 cB = 0.01 B = 0.1 dB), equal to exactly one-tenth of a decibel. This resolution is the standard for clinical audiometry and professional audio equipment. The pure-tone audiogram (ISO 8253-1, ANSI S3.21) records hearing thresholds at 5 dB (50 cB) steps for screening, but research audiometers adjust in 0.25 dB (2.5 cB) steps for precise threshold measurement. The human just-noticeable difference (JND) for loudness of a 1 kHz tone at 70 dB SPL is ≈ 1–3 cB (Moore, 2012), rising to 5–10 cB near the absolute hearing threshold. IEC 60268-5 specifications for loudspeakers require frequency response plots with centibel (0.1 dB) resolution. In studio monitor calibration (SMPTE RP 200, ITU-R BS.1116), loudspeaker level matching is verified to within 0.1 dB (1 cB). 1 cB = 0.01 B = 0.1 dB ≈ 0.011513 Np.

About Millibels

The millibel (mB) is one-thousandth of a bel (1 mB = 10⁻³ B = 0.01 dB), the finest routine subdivision of the bel family in widespread practical use. The AES17-2015 standard for digital audio converter measurement requires frequency response flatness within ±0.01 dB (±1 mB) across 10 Hz–20 kHz for a reference-quality interface. Audiometer calibration (IEC 60645-1, ANSI S3.6) specifies attenuator step accuracy to ±0.1 dB (10 mB) for research-grade psychoacoustic instruments. Modern audio codec chips (ESS Sabre ES9038PRO) specify passband ripple to 0.01 dB = 1 mB. In broadcast loudness metering (EBU R128, ITU-R BS.1770), integrated loudness is calculated at 0.1 LU = 10 mB resolution. IEC 61672-1 Class 1 sound level meters achieve frequency response flatness within ±0.7 dB (70 mB) from 31.5 Hz to 8 kHz. 1 mB = 0.001 B = 0.01 dB ≈ 1.151 × 10⁻³ Np.

Quick Reference Table

→ Full Sound Level Converter