An audiogram is a graph that displays the results of your hearing test. Once you learn how to read and interpret your audiogram, you will better understand your hearing loss. Your hearing care professional will use the results to help determine the best type of hearing aid for you.
The goal of audiometric testing is to measure your hearing ability across a range of frequencies in each ear.
The audiogram plots your hearing thresholds across various frequencies, or pitches. A hearing threshold is defined as the softest sound you are able to detect about 50% of the time. So don’t be surprised if you feel like you “missed” some of the beeps during your test.
How to read an audiogram
Looking at the audiogram graph, you will see two axes:
The horizontal axis (x-axis) represents frequency (pitch) from lowest to highest. The lowest frequency tested is usually 250 Hertz (Hz), and the highest is usually 8000 Hz. Most speech falls into the 250 to 6000 Hz range, with the vowel sounds being the lowest frequencies and the consonants such as S, F, SH, CH, H, TH, T and K sounds being the highest frequencies.
The vertical axis (y-axis) of the audiogram represents the intensity (loudness) of sound in decibels (dB), with the lowest levels at the top of the graph. Even though the top left of the chart is labeled -10 dB or 0 dB, that does not mean the absence of sound. Zero decibels represents the softest level of sound that the average person with normal hearing will hear.
What do the symbols on an audiogram mean?
Testing with headphones is called air conduction testing because the sound must travel through the air of the ear canal to reach the inner ear. The air conduction results for the right ear are marked with a red “O,” and the results for the left ear are marked with a blue “X.”
The important thing to understand is that the responses from the left ear are represented in blue, and those from the right ear are represented in red. Each symbol on the chart represents your threshold for a given frequency. In the example above, the individual’s threshold for 2000 Hz was 50 dB in each ear. Once all of the thresholds are measured and plotted on the graph, they are connected to form easy-to-read lines for the left and right ears.
If the two lines are essentially overlapping, your hearing loss is considered symmetrical, or the same in both ears. If the lines are not overlapping your hearing loss is considered asymmetrical, meaning your ears have differing degrees of hearing loss.
What is normal hearing on an audiogram?
Looking at the above audiogram, normal hearing ability is represented in the blue shaded area above the 25-dB line that crosses the graph from left to right. If your threshold symbols fall in the blue-shaded area, your hearing ability is considered within normal limits. Any symbols below that shaded area, however, indicate hearing loss at those frequencies.
Your hearing care professional will classify the severity of your hearing loss, by where the symbols fall on the graph. Hearing loss is often classified as slight, mild, moderate, moderate-to-severe, severe or profound. They will also describe the pattern of your loss, generally as flat, sloping or rising.
The space between the normal hearing area and your threshold symbols represents all of the sounds you’re missing because of your hearing loss. The bigger the space, the more sounds you’re not hearing. For most people with hearing loss, hearing aids can be a solution to bridge that gap and give you back the sounds you’re missing.
What’s a normal hearing level on an audiogram?
An adult is classified as having normal hearing ability if their responses indicate they heard noises between 0 and 25 dB across the frequency range. A child is considered to have hearing ability within normal limits if their responses are between 0 to 15 dB across the frequency range.