Lung sounds are listened to at specific locations on the front, back, and sides of the chest, with the stethoscope placed directly on the skin at each point. A complete lung exam typically covers 12 to 14 sites, moving symmetrically from side to side so you can compare the left and right lungs at matching levels. Each location corresponds to a different lobe or airway structure underneath, and the type of breath sound you hear changes depending on where you listen.
Anterior Listening Points
The front of the chest gives you access to the upper and middle portions of the lungs. Start at the top, just above the collarbones in the small dip on each side (the supraclavicular area). This captures the very top, or apex, of each lung.
Move down to the 1st and 2nd intercostal spaces, the gaps between the first few ribs on either side of the breastbone. These are key spots because they sit right over the large airways branching into each lung. The sounds here are medium-pitched, with roughly equal loudness during breathing in and breathing out. These are called bronchovesicular sounds, and hearing them in this location is normal.
Continue working downward to the 3rd and 4th intercostal spaces on each side. As you move further from the central airways and over more lung tissue, the sounds become softer and lower-pitched. These quieter sounds, called vesicular breath sounds, are loudest when you breathe in and fade quickly during exhalation. You should hear them across the full span of the lung fields on both sides. On the right side of the chest, the area around the 4th and 5th ribs overlies the right middle lobe, a section of lung that can only be assessed from the front and side.
Right over the top of the breastbone (the manubrium), you can hear bronchial breath sounds. These are loud, hollow, and high-pitched, similar to the sound of air moving through a large tube. Hearing bronchial sounds here is completely normal because the trachea sits directly behind this spot. Hearing that same loud, hollow quality out over the lower lung fields, however, would be abnormal and could suggest fluid or consolidation in the lung tissue.
Posterior Listening Points
The back of the chest is the most important surface for a thorough lung exam because it provides the widest access to the lower lobes, which make up the largest portion of both lungs. Have the person sit upright and lean slightly forward with their arms crossed in front of them. This pulls the shoulder blades apart, exposing more of the rib cage.
Begin between the shoulder blades (the interscapular area), roughly between the vertebrae at the base of the neck and the mid-upper back. This zone overlies the large bronchial airways, so you’ll hear bronchovesicular sounds here, just as you do at the 1st and 2nd intercostal spaces on the front. Below the back of the neck, between the C7 and T3 vertebrae, bronchial sounds are also normal because the trachea and its first branches sit just beneath.
From there, move outward and downward in a zigzag pattern. Place the stethoscope on one side, then cross to the matching spot on the opposite side before dropping down a level. This side-to-side comparison is the core technique of lung auscultation: you’re checking whether the two lungs sound symmetric at every level. Any difference in volume, pitch, or character between matching spots is a meaningful finding.
Work all the way down to the bases of the lungs, which extend to about the 10th or 11th rib in the back. The lower posterior fields should produce soft vesicular sounds. Reduced or absent sounds at the bases can indicate fluid around the lung or air trapped in the chest cavity.
Lateral Listening Points
The sides of the chest, along the midaxillary line (an imaginary vertical line running from the center of the armpit straight down), are often overlooked but cover important territory. On the right side, the lateral chest wall is the best place to assess the right middle lobe and the lower portion of the right upper lobe. On the left, the lateral field helps capture the lingula, a tongue-shaped projection of the left upper lobe that serves a similar function.
Listen at two or three levels on each side: one in the upper axillary area, one at mid-chest, and one near the bottom of the rib cage. You should hear vesicular sounds throughout these fields. Asking the person to raise their arm on the side you’re listening to can make it easier to get good stethoscope contact between the ribs.
Mapping the Chest Wall to Lung Lobes
Knowing which lobe you’re listening to matters because different diseases affect different lobes. The major fissure, which separates the upper and lower lobes, follows a line from the T2 vertebra (upper back) diagonally down to where the 6th rib meets the breastbone in front. A quick shortcut: if the person raises their hands above their head, the inner edge of the shoulder blade roughly traces the path of this fissure.
On the right side, a minor fissure separates the upper lobe from the middle lobe. It runs roughly horizontally from where the 4th rib attaches to the breastbone out to meet the major fissure. Everything below the minor fissure on the front right chest is the middle lobe; everything below the major fissure on the back is the lower lobe. The left lung has no middle lobe, so its territory is split between just two lobes.
In practical terms, this means the posterior chest below the shoulder blades is almost entirely lower lobe on both sides. The front upper chest above the 4th rib is upper lobe. And the right front chest between the 4th and 6th ribs is the middle lobe, best reached from the front and lateral surfaces.
The Side-to-Side Comparison Technique
The standard approach is to move the stethoscope in a zigzag or “ladder” pattern: listen to one spot, then immediately listen to the mirror-image spot on the opposite side. Start at the top (apices), compare left and right, then drop one level and repeat. This pattern applies on the front, back, and sides of the chest. Most complete exams include at least six spots on the posterior chest (three levels, both sides), four on the anterior chest (two levels, both sides), and two to four laterally.
At each site, have the person breathe in and out through an open mouth, slightly deeper than normal. Breathing through the nose or taking shallow breaths can muffle the sounds. Listen for at least one full breath cycle at each location before moving on.
Choosing the Right Stethoscope Side
Most stethoscopes have two sides: a flat, wide diaphragm and a smaller, open bell. The diaphragm filters out low-frequency vibrations and highlights higher-pitched sounds, making it the better choice for most lung auscultation. Normal breath sounds and common abnormal sounds like wheezes and fine crackles all fall in the higher frequency range.
The bell picks up lower-frequency sounds more effectively. It can be useful for detecting certain low-pitched abnormalities, but for a standard lung exam, the diaphragm is the default. Press it firmly enough to make full contact with the skin, but not so hard that it stretches the skin taut, which can create friction artifacts. Accurate positioning and full contact with the chest wall are essential for picking up subtle sounds, especially lower-frequency ones.
What Each Sound Tells You
Normal breath sounds exist on a spectrum. Bronchial sounds (loud, high-pitched, hollow) are normal only over the trachea and manubrium. Bronchovesicular sounds (moderate pitch, equal on inhalation and exhalation) are normal over the upper sternum and between the shoulder blades. Vesicular sounds (soft, rustling, louder on inhalation) are normal everywhere else across both lung fields.
The clinical value of knowing these locations is straightforward: if you hear a sound type in the wrong place, something has changed in the underlying lung tissue. Bronchial sounds heard out over the lower lung fields, for example, suggest that normally air-filled lung tissue has become dense, as happens with pneumonia. Absent or diminished sounds in an area that should have clear vesicular breath sounds may point to a collapsed lung, fluid buildup, or severe air trapping. Sounds that don’t fit any normal category, like wheezes, crackles, or a harsh grating noise, are always abnormal regardless of location and warrant further evaluation.