Difference Between Rales and Rhonchi

By: | Updated: Dec-31, 2022
The contents of the Difference.guru website, such as text, graphics, images, and other material contained on this site (“Content”) are for informational purposes only. The Content is not intended to be a substitute for professional medical or legal advice. Always seek the advice of your doctor with any questions you may have regarding your medical condition. Never disregard professional advice or delay in seeking it because of something you have read on this website!

Breathing allows you to do the most important things that are involved in keeping you alive. If you can’t exchange oxygen with your body by breathing, all your organs are not able to provide the energy that is needed to perform their functions properly. If the air in your lungs stops receiving enough oxygen, the brain and other vital organs can begin to die in the matter of minutes.

Summary Table

Rales Rhonchi
Rales are short breaths that are unusual because they are usually accompanied by intermittent crackles in the air. Rhonchi sounds like a breath that continuously crackles.


This becomes more prominent as we finish our periods of inspiration. It is also more prominent when you are about to breathe out as you are about to expire.


Generally, it is because of the moisture that is present in the airways. This happens when the airway narrows when fluid in the airway clogs the lumen of the artery.


Difference Between Rales and Rhonchi

Modern diagnostic tools allow doctors to use new technologies to identify problems with the lungs, but auscultation, or tuning in to the sound of what you are hearing, helps you understand what is really going on.

These can all be signs of issues when additional sounds are made or when the normal breath sounds are absent. Adventitious lung sounds are another name for abnormal breathing noises. When you breathe in and out, a stethoscope will pick up any extraneous or unexpected sounds. Let’s discover the various forms of abnormal breath sounds.

What are Rales?

Rales is a sound that occurs when you take a deep breath (OR, when you breathe deeply). They are characterized by a discontinuously crackling or popping sound. Air is constantly being pushed down humid airways, which leads to an abnormal rales sound.

Fine rales occur when air passes through smaller airways in the lungs, such as bronchial tubes, and are easily heard at the end of inspiration. Good rales are normally heard in the alveoli and bronchioles or when a person is inspiring. It is possible to hear these rales at the end of inspiratory breaths.

Rales are sounds that are much higher pitched than normal sounds, also called bibasilar crackles. Rales are higher-pitched sounds that occur when air passes through a closed space. These are sounds that are created when air is pushed into small spaces. It may occur in some parts of the lungs, such as the alveoli, which are very small sacs that hold air. Small sacs that hold tiny amounts of air that continually expand and contract with every breath. When tiny sac-shaped hollows are broken or filled with fluid or mucus, they may crackle and go loud when they try to get some air inside.

What is Rhonchi?

Rhonchi are the breath sounds that are produced when fluid is partially blocking the airway. There is less room for the air particles to move freely due to the fluid level inside the airway lumen, which results in a vibratory effect. Rhonchi are audible throughout respiration, but they are most audible during expiration.

Rhonchi are split into two groups based on the pitch of the sound they produce. Low-pitched sibilant rhonchi are made when air moves through constricted airways. When air moves through wide air passages, sonorous rhonchi with a high pitch are created.

This low-pitched sound typically emanates from the lungs’ larger airways. It is frequently compared to the sound of snoring and can be heard on either the inhalation or exhalation. Rhonchi can either continuously breathe in and out or come and go. When something, such as fluid, is obstructing the airway, these sounds are made. The noise you hear is caused by the air moving around the obstruction.

Difference Between Rales and Rhonchi

How are They Related?

Rhonchi and rales are two examples of abnormal breath sounds picked up during the auscultation. Rales and rhonchi are two abnormal lung sounds picked up during auscultation. The intermittent clicking sound is a defining feature of rales. Rhonchi also have this clicking or rattling quality, but rhonchi differ from rales in that the sound is continuous.

The main distinction between rales and rhonchi is this. Although correctly identifying the sound may seem like a simple task, it actually requires years of practice and a trained ear to distinguish between the two conditions using a stethoscope.

Even a simple sound that you make while you are breathing tells you a lot of important information. Some people have breathing problems that cause their air to sound strange. If any of your sounds are very strange or if your symptoms persist, see a doctor.

What are the Differences?

The Causes

Rhonchi are caused when something secretes or blocks a large area of the airway. These breathing sounds occur with many lung conditions, including asthma, bronchiectasis, pneumonia, or cystic fibrosis.

Rales happen when the small air sacs in the lungs, known as alveoli, spontaneously expand when there is mucus in the lungs.  Some of the conditions that can occur when there are many rales are: pulmonary embolism, pulmonary edema, and pulmonary fibrosis.

The Sound

When there is a free liquid in the airway passages, rhonchi sounds are produced. Moving air creates a high or low pitch vibration sound by simply vibrating some air through a vibrating device. Rales are a word from Latin which means to “blow” and are also called crackles. These sounds arise when airways in our bodies become obstructed while we are breathing; they are more notably emitted when we are inspired.

(Visited 147 times, 1 visits today)
Did this article help you?
Thank you!
Thank you!
What was wrong?