Note Frequency Calculator
Convert any musical note to its frequency in Hz — or enter a frequency to find the note name. Essential for singers testing their range.
Note Name → Frequency
Enter note name like C4, A#3, Bb4, F#5. Standard tuning: A4 = 440 Hz.
Frequency (Hz) → Note Name
Enter frequency in Hz (e.g. 440 = A4, 261.63 = C4, 523.25 = C5).
Vocal Range Reference Chart
All notes from C2 to C7 — covering the complete range of human singing voices. Middle C = C4 = 261.63 Hz.
| Note | Frequency (Hz) | MIDI # | Voice Type Zone |
|---|
When you test your vocal range, use our microphone tool to detect your lowest and highest comfortable notes. Then look them up in this chart to understand exactly where they sit in the vocal spectrum and which voice type range they correspond to.
Middle C = C4 = 261.63 Hz. The passaggio for sopranos and tenors occurs around E4 (329.63 Hz) to F4 (349.23 Hz). Baritone and mezzo passaggio: around C4–D4 (261–293 Hz).
Vocal Registers & Their Frequency Ranges
The singing voice uses different physical mechanisms called registers — each with a distinct frequency range, tone quality, and physiological process.
| Register | Approx. Hz Range | Note Range | Who Uses It |
|---|---|---|---|
| Chest Voice | 80 – 400 Hz | E2 – E4 approx. | All voice types; primary lower register |
| Mixed Voice | 300 – 700 Hz | D4 – F5 approx. | Critical zone for sopranos, tenors, mezzosBridge between chest and head registers |
| Head Voice | 500 – 1,200 Hz | C5 – D6 approx. | Upper range for all voices; resonates in head |
| Falsetto | 300 – 700 Hz (males) | E4 – A5 (males) | Airflow-dominant, breathy quality; males primarily |
| Whistle Register | 1,000 – 3,000+ Hz | C6 and above | Rare; sopranos and coloraturas only (Mariah Carey) |
Equal Temperament & A440 Explained
Every frequency in this calculator is based on the equal temperament tuning system with a reference pitch of A4 = 440 Hz. Here's why that matters for singers.
What Is A440?
A4 = 440 Hz is the international standard tuning reference, adopted in 1939. It's the A above middle C on a piano. Almost all modern instruments, digital tuners, and recordings use this reference. Some orchestras tune to A=442 or A=443 Hz for a brighter sound.
The Semitone Ratio
In equal temperament, each semitone up multiplies the frequency by the 12th root of 2: ≈ 1.05946. So A4 (440 Hz) × 1.05946 = A♯4 (466.16 Hz). An octave doubles the frequency: A4 = 440 Hz → A5 = 880 Hz.
Cents
A cent is 1/100th of a semitone — the smallest unit of musical pitch measurement. A tuner shows cents deviation: ±50 cents is a quarter tone; ±100 cents is one semitone. Singers typically aim for within ±10 cents of the target pitch.
Why It Matters for Singing
When you warm up or test your range, knowing the exact Hz of a note helps you calibrate to a digital tuner or piano. If a note sounds flat by 30 cents, you know you need to raise it slightly — not a full semitone, just a subtle adjustment in support and resonance.
Frequently Asked Questions
What is A440 and why is it the standard? +
A440 refers to the note A4 having a frequency of 440 Hz. It became the international standard in 1939 (ISO 16) to ensure that musicians around the world could tune to the same pitch. Before standardisation, orchestras used varying references ranging from A=415 Hz to A=460 Hz.
Why does the frequency double with each octave? +
This is a fundamental property of sound waves. A note one octave higher vibrates at exactly twice the frequency, producing a wave with half the wavelength. The human ear perceives these double-frequency notes as "the same note, higher" because of how the cochlea processes harmonic relationships.
How do I tune my voice to a specific note? +
Use this tool to find the Hz of your target note, then use the ▶ Play button to hear it. Sing along and adjust your pitch until your voice blends seamlessly with the tone. A chromatic tuner app on your phone can also show you your current pitch in real time, displaying the note name and cents deviation.
What is the difference between Hz and cents? +
Hz (hertz) measures the absolute frequency of a sound wave in cycles per second. Cents measure relative pitch deviation — 100 cents = 1 semitone. Hz values grow exponentially across octaves (C4=261.63 Hz, C5=523.25 Hz), while cents are a linear scale for fine pitch comparison within a small range.