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Thyroid Anatomy: Getting to Know Your Thyroid Gland
Written by SiPhox Health Research Team
Last updated: October 15, 2026
3 mins read
Where is your thyroid located?
Your thyroid is a small, butterfly-shaped gland located at the front of your neck, just below your voice box (larynx).
It sits in front of your windpipe (trachea) and is surrounded by muscles, blood vessels, and other important structures.
In most adults, the thyroid weighs approximately 15–25 grams, although its size and shape can vary naturally between individuals.
What does your thyroid look like?
Your thyroid has three main structural components:
- Right and left lobes: The two larger, wing-shaped sections on either side of your windpipe.
- Isthmus: A narrow bridge of tissue connecting the two lobes.
- Outer capsule: A thin layer of connective tissue surrounding the gland and helping maintain its structure.
Some people also have a small additional extension called a pyramidal lobe. This is a normal anatomical variation.
What’s inside your thyroid?
Although your thyroid appears to be a solid gland, it contains thousands of tiny, rounded structures called thyroid follicles.
Each follicle is lined with specialized thyroid cells and contains a gel-like substance called colloid.
The gland also has an extensive network of small blood vessels and connective tissue supporting its internal structure.
These microscopic features give the thyroid its distinctive appearance under a microscope.
What are the parathyroid glands?
Located behind or near your thyroid are several much smaller glands called the parathyroid glands.
Most people have four, although the number and exact location can vary.
Despite their similar names, the thyroid and parathyroid glands are separate structures with different functions.
Can the structure of your thyroid change?
Like other organs, your thyroid can develop changes in its size or appearance.
Some common structural findings include:
- Thyroid nodules: Small lumps or growths within the gland. Most are benign.
- Goiter: An enlargement of the thyroid gland.
- Thyroiditis: Inflammation that can sometimes cause swelling or changes in the gland’s appearance.
A thyroid ultrasound can help healthcare providers examine the gland’s size, shape, and internal structure.
Importantly, structural changes can occur even when thyroid blood test results are within normal ranges.
Why understanding thyroid anatomy matters
Knowing where your thyroid is located and how it is structured can help you better understand thyroid examinations, ultrasound findings, and common anatomical changes.
While blood tests provide information about thyroid function, imaging techniques such as ultrasound help evaluate its physical structure.
Key takeaway: Your thyroid may be small, but it has a surprisingly complex structure. Understanding its anatomy is a useful first step toward learning more about thyroid health.