Speech Clarity Tester
This speech clarity tester is a free voice clarity test that builds your long-term spectral balance across speech bands and a consonant-presence score — a proxy for how crisp your consonants are — with practical tips. Just read a few sentences into your mic.
ℹ This measures spectral balance, not true intelligibility. A real intelligibility metric (like STI) needs reference signals and room measurement; the “clarity” here is the energy in the 2.5–6 kHz consonant band relative to the rest of your speech — useful for spotting a muffled or harsh balance, but affected by your mic and room and not a clinical or pass/fail test. Your mic is analyzed live and never recorded or uploaded.
How It Works
While you speak, the tool builds a long-term average spectrum — the average energy at each frequency over the whole sample (only counting moments when you’re actually talking). The chart shows the speech bands: low-mid (vowel warmth, roughly 300–800 Hz), mid (vowel core, 800 Hz–2.5 kHz), presence (2.5–6 kHz — where consonant detail and high-frequency speech cues live), and air (above 6 kHz — sibilant brilliance and overall brightness), setting aside the sub-300 Hz rumble/body region. Crisp, clear speech carries a healthy share of energy in the presence band, because that’s where fricatives (s, f, sh), plosive bursts (t, k, p) and the edges of words sit. The score is the presence band’s share of that speech energy, scaled to 0–100 — so it matches the cyan Presence bar. Everything runs live on your device; nothing is recorded.
It’s a useful diagnostic for a muffled balance (too little presence — soft consonants, hard to follow on calls or in podcasts) or a harsh/sibilant one (too much presence, causing listener fatigue). It is also a practical aid for anyone working on their presentation voice, since crisp consonants and a balanced spectrum are key to holding an audience. But it is not a true intelligibility score: real speech intelligibility depends on articulation, pacing, background noise, and the listener, and proper Speech Transmission Index (STI) measurement uses calibrated reference signals and accounts for reverberation time. Your mic’s own frequency response also colours the result — a cheap headset mic often rolls off the presence band, making any voice sound less crisp. Compare changes on the same mic rather than chasing an absolute number. If you want to visualise how your consonants and vowels look moment by moment, try the speech frequency spectrogram alongside this tool.