Heart Location in Body Diagram – Chest and Ribs Labeled

All 13 parts on the diagram

Show the list

In the body 5

Heart It lies between the lungs, behind the breastbone. About two thirds of it is left of the midline.
Right lung The lung on the body's right side. The person faces you, so it is on your left.
Left lung The lung on the body's left side. The heart lies between the two lungs.
Diaphragm A sheet of muscle across the bottom of the chest. The heart rests on it.
Midline of the body An imaginary line down the middle of the body. More of the heart lies to its left.

Behind the ribs 8

Sternum (breastbone) The flat bone in the middle of the chest. The heart lies behind it.
Ribs The curved bones of the chest wall. Ten of the twelve pairs are drawn.
Costal cartilages Bars of cartilage that join the ribs to the sternum. Also called rib cartilages.
Apex of the heart The tip of the heart. It points down and to the body's left.
Fifth intercostal space The fifth gap between the ribs, counted from the top. The apex lies behind it on the left.
Right border The edge of the heart on the body's right. The right atrium forms it.
Left border The edge of the heart on the body's left. The left ventricle forms most of it.
Inferior border The lower edge of the heart. It ends at the apex.

How this list was compiled: Every name and place read on 2026-10-01 and kept only where two of these agree. Gray's Anatomy (1918, public domain), The Heart, https://theodora.com/anatomy/the_heart.html : the heart between the lungs in the middle mediastinum, behind the body of the sternum and the rib cartilages, one third right and two thirds left of the median plane, resting on the diaphragm; the apex behind the fifth left intercostal space; the right margin formed by the right atrium and the left margin mainly by the left ventricle. Gray's Anatomy (1918), Surface Markings of the Thorax, https://theodora.com/anatomy/surface_markings_of_the_thorax.html : the outline of the heart on the front of the chest, with its right and left borders and its lowest limit. TeachMeAnatomy, The Surfaces and Borders of the Heart, https://teachmeanatomy.info/thorax/organs/heart/borders-sinuses-sulci/ : right, left and inferior borders and the chambers that form them. SEER Training Modules, Structure of the Heart, U.S. National Cancer Institute, https://training.seer.cancer.gov/anatomy/cardiovascular/heart/structure.html : two thirds of the heart to the left of the midline. Wikipedia, Heart, Apex beat and Thoracic diaphragm, text only: the heart between the lungs and behind the sternum and rib cartilages, the fifth intercostal space, the diaphragm as a sheet of muscle. Twelve pairs of ribs: Gray's Anatomy (1918), The Ribs, https://theodora.com/anatomy/the_ribs.html , and Wikipedia, Rib cage. Licence: own work

The drawing: Drawn for this site on 2026-10-01 from plain geometry; the outline of the heart behind the ribs follows the surface markings described in Gray's Anatomy (1918, public domain). Own work; nothing traced. Licence: own work

How it works

The heart lies in the middle of the chest, between the lungs and behind the sternum, with about two thirds of it left of the midline. This heart and body diagram shows it in the body, then behind the ribs.

Read the full guide

In the body

The person faces you, so the body's left is on your right. The heart sits between the two lungs and rests on the diaphragm. The dashed midline shows the position of the heart in the body: the larger part is on the left side.

Behind the ribs

This heart and rib cage diagram draws the bones part see-through. The heavy lines are the right, left and inferior borders of the heart. The dot is the apex, behind the fifth intercostal space on the left.

Left and right are the body's own: the left lung is on the right of the drawing.

Questions and answers

Where is the heart located in the chest?

Between the two lungs, in the space called the mediastinum. It lies behind the sternum and the rib cartilages and rests on the diaphragm. About one third of it is to the right of the midline and two thirds to the left.

Is the heart on the left side of the body?

It is nearer the middle than most people think. The heart lies behind the sternum, but it is tilted, so about two thirds of it, and its tip, the apex, are to the left of the midline.

Which ribs is the heart behind?

It lies behind the body of the sternum and the rib cartilages beside it. Its apex reaches the fifth intercostal space on the left side, the gap between the fifth and sixth ribs.

What are the borders of the heart?

Seen from the front, the right border is formed by the right atrium, the left border mainly by the left ventricle, and the inferior border by the ventricles. The left and inferior borders meet at the apex.