Types and Degrees of Hearing Loss Explained

Hearing loss is typically described by its type and its degree, and both matter when you're trying to understand your hearing health, and deciding what to do next. If you've come across terms like "sensorineural" or "moderate hearing loss" and aren't sure what they mean, this article will walk you through them in plain language.

A quick reminder before we dive in: The only way to know your specific type and degree of hearing loss is through a hearing test. What follows is meant to help you understand the terminology, not to replace a professional evaluation.

3 Different Types of Hearing Loss

There are 3 main types of hearing loss, tied to the part of the ear that's affected: conductive (outer or middle ear), sensorineural (inner ear or nerve), and mixed (both).

Conductive Hearing Loss

Conductive hearing loss happens when sound can't travel efficiently through the outer or middle ear. Think of it as a blockage or mechanical problem — the inner ear is working fine, but sound has trouble getting there.

Common causes of CHL include:

• Earwax buildup blocking the ear canal;
• Fluid in the middle ear from a cold or allergies;
• Middle ear infections (otitis media);
• A perforated eardrum;
• Otosclerosis — a condition where the small bones in the middle ear stiffen and can't vibrate properly.

Conductive hearing loss is often temporary and can frequently be treated with medication or surgery. Because the inner ear and auditory nerve are intact, once the underlying cause is addressed, hearing often returns to normal or improves significantly. For cases that can't be fully resolved medically, hearing aids can help by amplifying sound enough to overcome the conduction problem.

Sensorineural Hearing Loss

Sensorineural hearing loss (SNHL) occurs when there's damage to the inner ear (the cochlea) or to the nerve pathways that carry sound signals to the brain. It's by far the most common type of all permanent hearing loss.

With SNHL, the problem is twofold: sounds need to be louder to be heard, and even when they are loud enough, speech can still sound muffled or unclear. This happens because the tiny hair cells in the cochlea — which convert sound vibrations into electrical signals — become damaged and don't grow back.

SNHL has many causes, and the most common ones include:

• Aging (presbycusis) — Gradual hearing loss that tends to come with getting older. About 30% of adults ages 65–74 have some degree of hearing loss. By 75, that rises to nearly 50%. It usually starts with high-pitched sounds — birds chirping, children's voices, the "s" and "th" sounds in speech — and works its way down.
• Noise exposure — Long-term exposure to sounds at or above 85 decibels (heavy city traffic, lawn mowers, power tools, loud music through headphones) or a single extremely loud event, such as a gunshot or explosion, can permanently damage the cochlea.
• Ototoxic medications — Certain drugs are toxic to the inner ear, including some antibiotics (aminoglycosides), chemotherapy agents (cisplatin), and high doses of aspirin or NSAIDs.
• Head injuries and trauma — Damage to the inner ear structures, auditory nerve, or brain regions involved in hearing.
• Genetics — Hearing loss can run in families, either present at birth or developing later in life.
• Viral and bacterial infections — Measles, mumps, meningitis, and cytomegalovirus (CMV) can all damage the inner ear.

Unlike conductive hearing loss, SNHL is usually permanent. No medication or surgery can reverse it. However, hearing aids and, in cases of severe-to-profound loss, cochlear implants can help you hear better and stay connected to the people and activities you enjoy. Our full guide to conductive vs sensorineural hearing loss goes deeper into each type and what sets them apart.

Mixed Hearing Loss

Mixed hearing loss is exactly what it sounds like — a combination of conductive and sensorineural hearing loss happening in the same ear. There is a problem in the outer or middle ear at the same time as damage in the inner ear or auditory nerve.

A practical example: someone who already has age-related SNHL develops an ear infection that adds a temporary conductive component on top of it. Treatment of mixed hearing loss usually targets the conductive part first (such as the ear infection), while the underlying SNHL is managed with hearing aids or other long-term solutions.

What Are the Degrees of Hearing Loss?

Type tells you where; degree tells you how much — specifically, the quietest sound you can detect at different pitches, measured in decibels (dB HL). These numbers come from a hearing test (an audiogram).

The World Health Organization published an updated hearing loss grading system in its 2021 World Report on Hearing. This is the most widely adopted international standard today. Older thresholds still float around, though — before 2021, WHO used different cutoffs (mild = 26–40 dB, moderate = 41–55 dB), and some clinics haven't transitioned. The table below follows the current 2021 system.

One thing worth noting: hearing loss rarely looks the same across all frequencies. You might have mild loss in the low pitches but moderately severe loss in the high pitches — which is common with age-related hearing loss. That's why an audiogram gives a complete picture that a single "degree" label only summarizes.

That said, a few patterns tend to show up at each level. Mild hearing loss often hides — conversation in a quiet room feels fine, and the difficulty only surfaces in noise, along with that drained feeling known as listening fatigue. By the moderate-to-severe range, normal-volume speech starts slipping away without help, and people lean on lip reading or start bowing out of group settings. At the severe and profound end, only loud sounds get through, and safety itself depends on hearing aids, implants, or visual alerts for things like smoke alarms and sirens.

Different Shapes of Hearing Loss

Hearing loss rarely looks the same across all pitches. How your thresholds vary from low to high frequencies is called configuration — and it matters because it shapes your daily listening experience in very specific ways.

Two people can both have "moderate" hearing loss but completely different experiences. Someone with a high-frequency configuration misses the clarity sounds — "s," "th," "f" — and struggles in background noise. Someone with a flat configuration loses volume across the board and finds even one-on-one quiet conversation difficult. An audiogram maps this out visually, and it's one of the main reasons a professional hearing test gives you a fuller picture than any online screening can.

What Type of Hearing Loss Do Hearing Aids Help?

Hearing aids are most commonly used for sensorineural hearing loss, and they work by amplifying sound to compensate for the damaged hair cells in the inner ear. They can also help with conductive hearing loss when medical treatment isn't an option or doesn't fully resolve the problem. If your hearing loss might be from earwax, an infection, or fluid buildup, it's important to identify and treat that cause first. Using a hearing aid without addressing the underlying issue may mask a treatable condition.

Over-the-counter (OTC) hearing aids became available in the U.S. in October 2022. They are regulated by the FDA as medical devices for adults 18 and older with perceived mild to moderate hearing loss.

OTC hearing aids are not intended for:

• People under 18 years old
• People with severe or profound hearing loss
• Anyone experiencing sudden hearing loss, dizziness, ear pain, drainage from the ear, or significantly worse hearing in one ear

If any of these apply to you, the FDA recommends seeing a doctor — ideally an ear, nose, and throat (ENT) specialist — before using any hearing device.

Next Steps for Your Hearing

The bottom line is that most people with mild to severe sensorineural hearing loss can benefit from hearing aids, whether prescription or OTC models. A hearing test is the best first step. It tells you your type, your degree, and whether hearing aids are likely to help — and if so, which kind.

Here's a quick decision guide based on what you know:

• Haven't had a hearing test yet: Start there. A professional hearing test gives you your type, degree, and configuration — the three things you need before any buying decision.
• Mild to moderate SNHL, no red flags: OTC hearing aids may be a good fit. Look for FDA-cleared devices with a trial period.
• Conductive symptoms (earwax, infection, fluid): See a doctor first. Treat the underlying cause — don't buy a hearing aid until you know what's going on.
• Severe or profound loss, or any red flag (sudden loss, dizziness, ear pain, one-sided loss): See an audiologist or ENT for prescription hearing aids or a cochlear implant evaluation.

More Types of Hearing Loss

Beyond the main hearing loss types covered above, there are some more. These labels give additional context about when, how fast, or on which side the hearing loss occurs.

• Unilateral hearing loss: WHO defines unilateral hearing loss as having a PTA of less than 20 dB in the better ear AND 35 dB or greater in the worse ear. People with unilateral hearing loss may not have trouble in quiet one-on-one settings, but often struggle to locate where sounds come from and to follow conversations in noisy environments, since the brain relies on both ears to separate speech from background noise.
• Bilateral hearing loss: hearing loss in both ears. Most permanent hearing loss is bilateral, especially when it's caused by aging.
• Sudden hearing loss (SSNHL): a rapid loss of hearing, typically in one ear, that occurs over the course of 72 hours or less. SSNHL is considered a medical emergency. The standard treatment is corticosteroids, and starting treatment within the first few days gives the best chance of recovering some or all of the lost hearing. If you experience a sudden drop in hearing, see a doctor right away.
• Congenital hearing loss: hearing loss present at birth. It can be genetic (inherited) or result from complications during pregnancy or childbirth, such as premature birth, low birth weight, or certain infections during pregnancy like rubella or cytomegalovirus (CMV).
• Acquired hearing loss: hearing loss that develops after birth, at any age. Most hearing loss is acquired. Common causes include aging, noise exposure, ear infections, certain medications, and head injury.
• Noise-induced hearing loss (NIHL): hearing loss caused by exposure to loud sounds. Sounds at or above 85 decibels can damage hearing over time, and the damage depends on both how loud the sound is and how long you're exposed. NIHL is the one type of hearing loss that is entirely preventable — using hearing protection in loud environments, keeping headphone volumes at safe levels, and giving your ears regular breaks from noise all make a real difference.
• Age-related hearing loss (presbycusis): a gradual, progressive sensorineural hearing loss that comes with aging. It usually affects both ears equally and starts with difficulty hearing high-pitched sounds like children's voices or the chirping of birds. Over time, it progresses to affect more of the speech range. It's one of the most common chronic health conditions in older adults.

FAQs

How many types of hearing loss are there?

There are three main types of hearing loss: conductive, sensorineural, and mixed hearing loss. Beyond these, hearing loss can also be described by when it started (congenital or acquired), how fast it developed (sudden or gradual), and whether it affects one ear or both (unilateral or bilateral).

What type of hearing loss is caused by loud noises?

Noise-induced hearing loss (NIHL) is a form of sensorineural hearing loss. Loud sounds damage the hair cells in the cochlea, which don't regenerate once they're lost. The good news is that NIHL is almost always preventable. Using earplugs or earmuffs around loud noise, keeping personal listening devices at safe volumes, and taking listening breaks can protect your hearing over the long term.

What degree of hearing loss needs a hearing aid?

There's no single threshold at which everyone needs a hearing aid — it depends on your type and degree of hearing loss, your lifestyle, and how much your hearing affects your daily communication. Generally, people with even mild hearing loss (26–40 dB HL) can benefit from hearing aids, especially if they spend a lot of time in meetings, social settings, or other situations where clear hearing matters. People with moderate and moderately severe hearing loss almost always benefit significantly from amplification. OTC hearing aids are designed for adults with perceived mild-to-moderate hearing loss. For severe or profound loss, prescription hearing aids or cochlear implants are recommended under the care of an audiologist or ENT.

Can hearing loss be more than one type?

Yes. When someone has both conductive and sensorineural hearing loss in the same ear, it's called mixed hearing loss. This means there's a problem in the outer or middle ear at the same time as damage in the inner ear or auditory nerve. It's not uncommon — someone with long-standing age-related SNHL might develop a middle ear infection that temporarily adds a conductive component.

Disclaimer: This article is for informational purposes only and does not constitute medical advice. If your hearing loss is sudden, in one ear, or comes with pain, dizziness, or drainage, see a doctor first. Sudden hearing loss is a medical emergency that needs prompt treatment. Hearing aids are regulated medical devices; OTC hearing aids are intended for adults 18 and older with perceived mild-to-moderate hearing loss.