dB to Linear Converter

The difference lies in the mathematical relationship. Decibels for power use a factor of 10 in the conversion formula (10^(dB/10)), while decibels for amplitude (voltage, current, sound pressure) use a factor of 20 (10^(dB/20)). This is because power is proportional to the square of amplitude, so the logarithmic relationship changes accordingly. For example:

• A +3 dB increase in power ≈ 1.995× the power.
• A +3 dB increase in amplitude ≈ 1.414× the amplitude.

The reference value defines your 0 dB baseline. Without a reference, dB values are meaningless because decibels are inherently relative measurements. Common references include:

• dBm: 1 milliwatt (0.001 W)
• dBV: 1 volt
• dB SPL: 20 micropascals (sound pressure)
• dBFS: Full scale (digital systems) If you're working with dimensionless ratios (e.g., gain/loss), use a reference of 1.

Yes! The tool supports bidirectional conversion. Simply enter your linear value in the "Linear Value" field, and the tool will automatically calculate the corresponding dB value using the appropriate formula based on your selected type (Power or Amplitude).

Negative dB values are perfectly valid and represent attenuation or values below the reference level. For example:

• -3 dB power = 0.5 linear (half the reference power)
• -20 dB amplitude = 0.1 linear (one-tenth the reference amplitude) The tool handles negative values correctly in all calculations.

The reference value must be greater than zero because:

1. Logarithms of zero or negative numbers are undefined in real mathematics.
2. A reference of zero would make the ratio calculation impossible (division by zero).
3. Negative reference values don’t have physical meaning in signal measurements. The tool validates this to prevent mathematically invalid operations.

The tool uses JavaScript’s native Math.pow() and Math.log10() functions, which provide double-precision floating-point accuracy (approximately 15–17 significant digits). Results are displayed with 6 decimal places by default, but the underlying calculations maintain full precision.

dB (decibel) is a dimensionless unit representing a ratio between two values. dBm (decibel-milliwatt) is an absolute unit that references 1 milliwatt. To use dBm values in this tool:

• Set the reference to 0.001 (1 milliwatt).
• Enter your dBm value as the dB input.
• The linear result will be in watts.

Absolutely! This tool is ideal for audio engineering tasks such as:

• Converting microphone sensitivity specifications (e.g., -40 dB to linear voltage).
• Calculating amplifier gains (e.g., +26 dB to linear power ratio).
• Working with sound pressure levels (SPL).
• Converting between dBV, dBu, and linear voltage values. For audio, you’ll typically use the Amplitude conversion type.

The tool itself doesn’t directly account for impedance, but you can use it as part of impedance matching workflows. Remember:

• Power conversion is independent of impedance.
• Voltage conversion assumes the same impedance on both sides.
• For different impedances, you’ll need to manually adjust the reference value or apply additional calculations.

The results are displayed in a code editor at the bottom of the tool. Simply click the copy button (📋) in the top-right corner of the results section to copy the formatted output to your clipboard.