An audiogram is a graph showing the quietest tones you responded to at different pitches in each ear. Pitch, or frequency, runs from low to high across the page. Hearing level in decibels runs from quieter at the top to louder lower down. Marks further down the graph therefore represent poorer hearing sensitivity at that frequency.
An audiogram is important, but it is not the whole assessment. NICE says adult audiological assessment should also include hearing history, communication needs, otoscopy and other tests where indicated. The result needs to be explained in relation to your life, not handed over as an unexplained graph.
What do the axes mean?
Frequency in hertz
The horizontal axis shows frequency, measured in hertz, Hz. Lower frequencies are toward the left and higher frequencies toward the right. A low-pitched rumble occupies a different part of the graph from higher-pitched consonant sounds.
Common test frequencies include 250, 500, 1,000, 2,000, 4,000 and 8,000 Hz. Intermediate frequencies may be tested when clinically useful.
Hearing level in decibels
The vertical axis is normally decibels hearing level, dB HL. It is a calibrated hearing-test scale, not the same as a simple sound-level reading in a room. Zero dB HL does not mean complete silence. It represents a reference level based on typical hearing sensitivity.
The clinician presents a tone and changes its level to identify the quietest response that can be repeated reliably. This threshold is plotted for each frequency.
What do the symbols mean?
Audiograms use conventional symbols, but the test provider should supply a key. Common unmasked air-conduction symbols include:
- A red circle for the right ear.
- A blue cross for the left ear.
Other symbols may represent masked testing, bone conduction, sound-field results or responses where no tone was heard at the equipment limit. Colour should never be the only way the ears are distinguished.
Do not interpret unfamiliar brackets, arrows or symbols without the key and clinical context.
What are air and bone conduction?
Air-conduction testing through headphones or insert earphones assesses the full pathway from the outer ear through the middle ear to the inner ear and auditory system.
Bone-conduction testing uses a small vibrator placed behind the ear or on the forehead. It bypasses much of the outer and middle ear to help identify whether a difference may involve sound transmission through those structures.
The relationship between air- and bone-conduction thresholds helps the clinician describe the broad type of hearing loss:
- Sensorineural patterns involve the inner ear or auditory pathway.
- Conductive patterns involve sound transmission through the outer or middle ear.
- Mixed patterns contain elements of both.
This distinction is clinical. It should not be diagnosed from an online example or self-read graph.
What counts as mild, moderate or severe hearing loss?
Terms such as mild, moderate, severe and profound describe threshold ranges, but classification systems and averaging methods vary. A single label can also hide an important sloping or asymmetric pattern.
Two people with the same average may have different difficulties because:
- Different frequencies are affected.
- One ear may be poorer than the other.
- Speech understanding may differ.
- Background noise and room acoustics create additional demands.
- Vision, cognition and communication context influence real-life listening.
Ask which frequencies are affected and what that is likely to mean for speech, not only which category appears on the report.
Why can speech be unclear when sounds are loud enough?
Hearing loss is not simply a volume control. If higher-frequency sensitivity is reduced, some consonants can be less available even when vowel energy is heard. Increasing overall volume does not always restore clarity.
NICE specifically recommends discussing hearing difficulties such as listening in noise that are not obvious from the pure-tone audiogram. Speech testing, reported experience and listening goals can therefore add important information.
What is the speech banana?
Some diagrams place a banana-shaped area over the audiogram to show where parts of conversational speech often occur. It can be a helpful illustration, but it is not a diagnostic boundary. Speech varies by talker, language, distance, room and level. Do not use the speech banana to select or programme a hearing aid.
What does an asymmetric audiogram mean?
Asymmetry means the ears differ. A small difference is not automatically alarming, but a marked or unexplained difference can require further investigation. NICE provides referral criteria involving unilateral or asymmetric hearing loss and certain accompanying symptoms.
Seek prompt professional advice for sudden or rapidly worsening hearing. NICE recommends immediate referral when sudden hearing loss developed over three days or less within the previous 30 days and is not explained by an outer- or middle-ear cause.
Other referral signs include facial weakness or altered sensation, persistent one-sided or pulsating tinnitus, recurrent vertigo, ear discharge, persistent pain and abnormal ear findings. This guide cannot assess those symptoms.
What can an audiogram not tell you?
An audiogram alone cannot fully show:
- How well you follow a particular speaker in a busy room.
- The effect of fatigue or listening effort.
- Whether wax or an abnormal eardrum is present without ear examination.
- Which hearing aid brand or technology level is best.
- Whether every symptom is caused by hearing loss.
- How much benefit you will receive from a specific device.
That is why a professional test includes questions, ear examination, measurement and explanation.
Questions to ask about your results
- Is the hearing loss similar in both ears?
- Which frequencies are most affected?
- Is the pattern conductive, sensorineural or mixed?
- Are any medical or specialist referrals indicated?
- How could this affect speech and background-noise listening?
- What non-device strategies may help?
- If hearing aids are appropriate, why are the recommended features suitable?
- When should hearing be reassessed?
Getting an audiogram at home
Hear Better's free adult home hearing assessment includes discussion of your hearing, examination of the ears, pure-tone measurement and an explanation of the results. If the findings indicate that further medical or specialist assessment is appropriate, that next step is explained. There is no obligation to purchase hearing aids.