The lines, symbols and numbers on your hearing test report — decoded in plain language, with no jargon.
Quick answer
An audiogram plots pitch (frequency in Hz) on the horizontal axis and loudness (dB HL) on the vertical axis. O marks the right ear, X marks the left. Thresholds between 0 and 25 dB HL are normal; 26–40 dB is mild loss, 41–55 dB moderate, 56–70 dB moderately severe, 71–90 dB severe, and 91 dB or worse is profound. A line sloping toward the bottom-right indicates high-frequency hearing loss.
Key takeaways
- X = left ear, O = right ear — lower on the chart means louder was needed.
- Speech frequencies sit between 500 Hz and 4,000 Hz.
- Normal adult hearing = 0–25 dB HL across all tested frequencies.
- High-frequency loss is the most common pattern with age and noise exposure.
- Mild loss can still deserve hearing aids when it affects work, safety or family life.
An audiogram is a simple line graph. Once you understand the axes, you can read yours in about three minutes.
The two axes
The horizontal axis is frequency (pitch) measured in Hertz — from low bass on the left (250 Hz) to high treble on the right (8000 Hz). The vertical axis is loudness in decibels, with the softest sounds at the top (0 dB) and loudest at the bottom (120 dB).
The symbols
- O = right ear (usually red)
- X = left ear (usually blue)
- The lower a symbol sits on the graph, the louder the sound needed for you to hear that frequency
The severity bands
- 0–25 dB — Normal hearing
- 26–40 dB — Mild loss
- 41–55 dB — Moderate loss
- 56–70 dB — Moderately severe loss
- 71–90 dB — Severe loss
- 91+ dB — Profound loss
The shape tells the story
A flat line means loss is even across frequencies. A downward slope (common with age or noise exposure) means high frequencies are affected first — which is why S, F and TH sounds fade before vowels do.
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Frequently asked questions
How do you read an audiogram?
The horizontal axis shows pitch (frequency in Hz, low on the left, high on the right); the vertical axis shows loudness (dB HL, quiet at the top, loud at the bottom). O marks the right ear, X marks the left. The lower a mark sits, the louder that pitch has to be for you to hear it — so lines that drop toward the bottom-right mean high-frequency hearing loss.
What is a normal audiogram result?
Thresholds between 0 and 25 dB HL across 250 Hz–8,000 Hz are considered normal for adults. 26–40 dB HL is mild loss, 41–55 dB HL moderate, 56–70 dB HL moderately severe, 71–90 dB HL severe, and 91 dB HL or worse is profound.
Why is my audiogram worse on high frequencies?
Age and noise damage the fragile hair cells in the base of the cochlea first — the ones that detect high frequencies (2–8 kHz). This is why consonants like S, F, TH and SH become unclear long before vowels, so speech sounds muffled but not quiet.
Do I need hearing aids if my audiogram shows mild loss?
Not always — the decision depends on how much day-to-day difficulty you have, whether you work in demanding listening environments, and whether family members notice. Modern hearing aids are strongly recommended for mild loss when it affects work, safety or social life, because early treatment protects speech understanding long-term.
Sources & further reading
We cross-checked this article against the following authoritative sources. Guidance and figures reflect the most recent public guidance available at the time of last review (July 2026). Clinical review by the Prudent Hearing clinical team.
- Understanding your audiogram — American Speech-Language-Hearing Association (ASHA)
- Deafness and hearing loss — World Health Organization (WHO)
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