Decibel (dB) Calculator
Convert between decibels, voltage ratios, power ratios, and volume percentages. Instantly.
200% volume = +6.02 dB gain. Every doubling of volume is approximately +6 dB. This is how apps like Loudify describe their boost — 500% = ~+14 dB.
Quick Reference: dB to Volume
| dB Change | Volume % | Perceived Change | Example |
|---|---|---|---|
| +1 dB | 112% | Barely noticeable | Minor EQ adjustment |
| +3 dB | 141% | Just noticeable | Doubling acoustic power |
| +6 dB | 200% | Clearly louder | Doubling voltage/amplitude |
| +10 dB | 316% | Twice as loud (perceived) | Quiet room → conversation |
| +14 dB | 500% | Much louder | 5x volume boost (Loudify) |
| +20 dB | 1000% | 4x as loud (perceived) | 10x volume boost (Loudify max) |
| -3 dB | 71% | Slightly quieter | Halving acoustic power |
| -6 dB | 50% | Noticeably quieter | Halving amplitude |
| -10 dB | 32% | Half as loud (perceived) | |
| -20 dB | 10% | Much quieter |
Frequently Asked Questions
What is a decibel (dB)?+
A decibel is a logarithmic unit used to measure the ratio between two values — typically power or amplitude. In audio, dB describes how loud a sound is relative to a reference point. Because it's logarithmic, a +10 dB increase sounds roughly twice as loud to human ears.
How much louder is +6 dB?+
A +6 dB increase doubles the amplitude (voltage) of the audio signal, which corresponds to 200% volume. It's clearly noticeable — about the difference between someone speaking normally and speaking with more projection.
What's the difference between dB, dBFS, and dB SPL?+
dB is a relative unit (ratio between two values). dBFS (decibels relative to full scale) measures digital audio levels where 0 dBFS is the maximum. dB SPL (sound pressure level) measures actual sound pressure in the air, where 0 dB SPL is the threshold of human hearing.
How do I convert volume percentage to dB?+
Use the formula: dB = 20 × log10(percentage / 100). For example, 200% = 20 × log10(2) = +6.02 dB. Our calculator does this instantly.
Need to boost a video's volume?
Loudify amplifies video audio up to 1000% (+20 dB). Free on iOS.