Headphone Power Calculator
Calculate power, voltage, and current requirements for your headphones
Headphone Specifications
Common values: 16Ω, 32Ω, 80Ω, 250Ω, 600Ω
Enter sensitivity in either format - the other will be calculated automatically
Recommended: 110 dB SPL for critical listening. Safe limit: 85 dB SPL for extended use.
Amplifier Requirements
Power Required
10.00 mW
0.0100 W
Voltage Required
0.566 V
RMS voltage
Current Required
17.68 mA
0.0177 A
Amplifier Impedance Recommendation
Less than 4.0 Ω
For optimal impedance matching (amplifier should be ≤ 1/8 of headphone impedance)
Calculation Formula
Power (mW) = 10^[(loudness - sensitivity)/10]
Power (mW) = 10^[(110 - 100.0)/10] = 10.00 mW
Voltage (V) = √(Power × Impedance) = √(0.0100 × 32) = 0.566 V
Current (mA) = Voltage / Impedance × 1000 = 0.566 / 32 × 1000 = 17.68 mA
Understanding Headphone Power
What is Headphone Impedance?
Impedance, measured in ohms (Ω), represents the opposition to current in AC circuits. Higher impedance headphones generally require more power to achieve the same volume level.
- Low impedance (16-32Ω): Easy to drive, work well with mobile devices
- Medium impedance (80-250Ω): May need dedicated amplifiers for optimal performance
- High impedance (300Ω+): Require dedicated headphone amplifiers
What is Headphone Sensitivity?
Sensitivity measures how efficiently headphones convert electrical power into sound. It's expressed as dB SPL/mW (sound pressure level per milliwatt) or dB SPL/V (per volt).
Conversion Formula
dB(mW) = dB(V) + 10 × log₁₀(Ω/1000)
Do You Need a Headphone Amplifier?
You need an amplifier if your source device cannot provide enough power to reach your desired volume level. Check if your amplifier can output the calculated power at your headphone's impedance.
Signs You DON'T Need an Amp
- • Headphones get loud enough at 70-80% volume
- • No distortion at higher volumes
- • Good dynamic range and clarity
Signs You NEED an Amp
- • Need to turn volume to 90%+ for adequate level
- • Sound becomes distorted at higher volumes
- • Lack of bass response or dynamics
Safety Guidelines
- 85 dB SPL: Safe for extended listening (8+ hours)
- 90 dB SPL: Safe for up to 2.5 hours per day
- 100 dB SPL: Safe for up to 15 minutes per day
- 110+ dB SPL: Use only for brief critical listening sessions