How to Read an Audiogram
An audiogram is the chart a hearing test produces. ASHA describes it simply: across the chart runs frequency in Hertz (Hz), and down the chart runs loudness in decibels (dB). The right ear is marked with a red O and the left ear with a blue X. Marks near the top mean the person heard quiet sounds; marks farther down mean a sound had to be louder to be heard.
The degree bands
| Degree (ASHA) | dB HL |
|---|---|
| Normal | -10 to 15 |
| Slight | 16 to 25 |
| Mild | 26 to 40 |
| Moderate | 41 to 55 |
| Moderately severe | 56 to 70 |
| Severe | 71 to 90 |
| Profound | 91 and above |
How this connects to buying
The FDA's OTC category is for adults with perceived mild to moderate hearing loss; no audiogram is required to buy one. ASHA's “mild” and “moderate” bands together span 26 to 55 dB HL. A test result also lets a fitted seller program a device, and the FDA notes buyers can request their evaluation records to shop elsewhere. Price lists: OTC and all models.
Sources
- ASHA: Degree of hearing loss and ASHA: Audiogram, checked October 20, 2026.
This guide explains how the chart is drawn. It cannot interpret anyone's results; an audiologist or physician does that.
Questions
What do the X and O mean on an audiogram?
ASHA says the right ear is marked with a red O and the left ear with a blue X.
What range counts as mild hearing loss?
ASHA publishes a band for each degree, from normal to profound; the table on this page lists every band in dB HL.