How to Read Your Audiogram: A Plain-Language Guide

AudiologyOctober 6, 20266 min read

An audiogram is a chart that shows the softest sounds you can hear at different pitches. Pitch (frequency) runs from low on the left to high on the right, and loudness (in decibels) runs from very soft at the top to very loud at the bottom. Each mark shows your hearing threshold for one ear at one pitch: the higher the marks sit on the chart, the better the hearing.

On most audiograms, O marks the right ear and X marks the left ear. If the marks sit near the top of the chart across all pitches, hearing is in the normal range. If they slope downwards or sit lower on the chart, there is some degree of hearing loss. After your hearing test, your audiologist will explain your own chart; knowing the basics makes that conversation easier.

What is an audiogram?

An audiogram is the main result of pure-tone audiometry, the part of a hearing test where you listen to tones and respond each time you hear one. If you would like to know how the test itself works, see Hearing Tests Explained: The Main Types and What Each One Shows.

The audiogram does not measure everything about hearing. It shows how loud sounds must be for you to detect them, not how clearly you understand speech, which is why speech tests are usually done as well.

How is an audiogram laid out?

The horizontal axis: pitch (frequency)

Across the top or bottom of the chart you will see frequencies measured in Hertz (Hz). Low-pitched sounds, such as a deep voice, a drum or many vowel sounds, are on the left. High-pitched sounds, such as birdsong, a whistle, and consonants like "s", "f" and "th", are on the right.

The vertical axis: loudness (decibels)

Down the side are loudness levels in decibels (dB HL, or "hearing level"). The top of the chart represents very soft sounds; moving down the chart, sounds get louder. A mark near the top means you can hear very quiet sounds at that pitch. A mark lower down means the sound had to be louder before you could hear it.

What do the symbols mean?

Audiograms use standard symbols, often with colour:

O (often red): right ear, tested through headphones or earphones (air conduction)
X (often blue): left ear, air conduction
< and >, or [ and ]: bone-conduction results, tested with a small vibrator behind the ear

Symbols can vary slightly between clinics, so there is usually a key printed on the chart.

How do you tell the type of hearing loss?

Comparing air-conduction marks (O and X) with bone-conduction marks shows where the problem lies:

Air and bone marks together, both in the normal zone: hearing within normal limits.
Air and bone marks together, both lower than normal: usually sensorineural hearing loss, coming from the inner ear or hearing nerve.
Bone marks normal but air marks lower: this "gap" between them suggests conductive hearing loss, where sound is blocked in the outer or middle ear.
Both lower, with a gap between them: mixed hearing loss.

For more on what each type means, read Hearing Loss: Types, Causes, Signs and What to Do Next.

What are the degrees of hearing loss?

Audiologists describe how much hearing loss there is using categories such as normal, slight, mild, moderate, moderately severe, severe and profound. The further down the chart your marks fall, the greater the degree. Many people have different degrees at different pitches, for example normal hearing in the low pitches and a moderate loss in the high pitches.

What do common audiogram shapes mean?

Sloping down to the right: hearing is better for low pitches than high pitches. This is very common with age-related hearing loss and explains why speech can sound loud enough but still lack clarity.
A dip or "notch" in the higher pitches: this pattern may be seen in people with a history of noise exposure.
Different shapes for each ear: a clear difference between the ears should always be discussed with your audiologist, and may need a medical opinion.

What questions should you ask about your audiogram?

Is my hearing within normal limits in each ear?
What type of hearing loss do I have, and how much?
Do I need to see a doctor about any of these results?
Would hearing aids or other support help, and why?
When should my hearing be checked again?

If hearing aids are discussed, Do I Need a Hearing Aid? Signs, Test Results and Next Steps explains how test results feed into that decision.

When to see a specialist

Talk to an audiologist if:

You have an audiogram but are unsure what it means
Your results show a difference between your ears
You notice hearing difficulties but have never had a full assessment

See a doctor promptly if hearing drops suddenly, if one ear is affected with ringing or dizziness, or if you have ear pain with discharge.

At our centre in Bousher, Muscat, our audiologist carries out hearing tests and explains each result in plain language. No referral is needed.

You can book an appointment online or contact us if you are not sure which service you need.

Frequently asked questions

What do X and O mean on an audiogram?

O marks the results for the right ear and X marks the left ear, both tested through headphones or earphones (air conduction). They are often shown in red for the right ear and blue for the left. Other symbols, such as brackets or arrows, usually show bone-conduction results.

What is considered normal hearing on an audiogram?

Normal hearing is shown by marks near the top of the chart across the tested pitches, meaning you can hear very soft sounds. The exact cut-off point varies slightly between references and between adults and children. Your audiologist will tell you whether your results are within normal limits for each ear.

Can I get a copy of my audiogram?

It is reasonable to ask for a copy of your results, and keeping one is useful for comparing tests over time or sharing with a doctor. Ask at your appointment. Make sure someone explains the chart to you, rather than relying on the numbers alone.

Sources

This article is general information and does not replace advice from a qualified professional.

Adult Hearing Tests & Assessment Ashfeera Ashraf