Calculate the decibel difference between two sound intensities — free, using the real logarithmic formula.
Calculate the decibel difference between two sound intensities — enter any two intensity values in the same units (they don't need to be in any particular unit, since decibels are a ratio, not an absolute measurement) and get the difference in dB.
Decibels are logarithmic specifically because human hearing perceives loudness roughly logarithmically, not linearly — the formula is 10 × log₁₀(I₁/I₂), which is why a sound with 10 times the intensity is "only" 10dB louder, and why every +3dB roughly corresponds to doubling the actual intensity, not adding a fixed amount.
This calculates a relative difference between two intensity values you provide — it doesn't measure real sound through your device's microphone or know standard reference levels for specific real-world sounds.
Because decibels are logarithmic — 10×log₁₀(2) ≈ 3.01, a direct consequence of the formula. Perceived loudness roughly matches this logarithmic scale, which is exactly why decibels were defined this way rather than as a simple percentage.
No — it calculates the mathematical difference between two intensity numbers you enter yourself, not a live measurement from your device’s microphone.
No — since the result is a ratio, any consistent unit works as long as both values use the same one; the units themselves cancel out in the calculation.