Headphone Power Calculator

Includes Loudness (SPL) Estimation

Wondering if your headphones are adequately powered—or how loud they’ll get? Our Headphone Power Calculator uses your headphone’s impedance and sensitivity to compute the power and estimated loudness (in dB SPL) you can expect from your device. Perfect if you’re deciding whether you need a dongle, DAC, or amp.

Headphone Power Calculator — Includes Loudness (SPL)

Headphone Power Calculator

Compute required voltage, current, and power for your target loudness, and estimate max SPL from your source. Includes sensitivity unit toggle (dB/mW ⇄ dB/V) and export.

Inputs

Presets are approximate; use exact specs if you have them.
You can fine-tune voltage below.
From the spec sheet (typically 16–600 Ω).
Switch to match how your specs are listed.
Example: 100 dB/mW or 97 dB/V.
Typical: 85–100 dB for music peaks. Use 100 for robust headroom checks.
Your phone/dongle/amp max voltage. Preset can set this.
Included in exports & copy summary.

These are **engineering estimates** from typical formulas. Real-world loudness varies by recordings, EQ, limiters, and fit/seal.

Results

Required Voltage (Vrms) for Target

—
For 100 dB SPL

Required Power (mW)

—
At 32 Ω

Required Current (mA)

—
I = V / R

Estimated Max SPL (dB)

—
From 2.0 Vrms
Calculating…
—
TargetHeadroomLimit
Needle shows your target vs. estimated max SPL.

Sensitivity (normalized)

— dB/mW
— dB/V

Source @ Max

— mW
— mA @ 32 Ω

Tip: For music with wide dynamics, aim for ≥ 10 dB headroom above your typical target SPL.

How this works

Key formulas used by this calculator:

From dB/mW
Required power: PmW = 10^((Target − SensdB/mW)/10)
Voltage: V = √(PW · R) where PW=PmW/1000
From dB/V
Required voltage: V = 10^((Target − SensdB/V)/20)
Max SPL
From voltage: Max = SensdB/V + 20·log10(V)
(equivalent via power/Ω)
Headphone Power Calculator – Check how loud your headphones can get

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Headphone Power Calculator FAQs

What is a Headphone Power Calculator?

A Headphone Power Calculator estimates the voltage, current, and power your headphones need to reach a target loudness (dB SPL). It also shows max SPL from your source so you know if a phone, dongle, or amp is powerful enough.

Will my phone or dongle drive my headphones loud enough?

Enter your headphone specs, set your target SPL, and choose a source preset. The calculator displays headroom in dB and a verdict: Excellent, Sufficient, Borderline, or Insufficient.

Do I need a headphone amp?

If headroom is less than ~6–10 dB for your target loudness, a stronger source (USB-C dongle or amp) is recommended. High-impedance or low-sensitivity headphones especially benefit from an amp.