Bruises turn green because your body is actively breaking down trapped blood beneath the skin. Specifically, an enzyme called heme oxygenase converts the dark pigment in hemoglobin into a green compound called biliverdin. That green stage is a sign your bruise is healing, not getting worse.
What Happens Under the Skin
When you bump into something hard enough to break tiny blood vessels beneath the skin, blood leaks into the surrounding tissue. That pooled blood is what you see as a bruise. Your body treats this leaked blood as debris that needs cleaning up, and it sends specialized immune cells called macrophages to the site to start digesting the red blood cells and recycling their components.
Hemoglobin, the protein that makes blood red, contains a pigment called heme. As macrophages break down the trapped red blood cells, heme goes through a series of chemical conversions. Each stage produces a different pigment with a different color, which is why a bruise shifts through a rainbow over its lifetime. The green you see is one specific stop along that recycling process.
Why Green Specifically
The green color comes from biliverdin, a pigment created when heme oxygenase breaks apart the heme molecule. Biliverdin absorbs red and blue light and reflects green light back to your eyes. It’s the same reason bile has a greenish tint: biliverdin is produced wherever your body breaks down old red blood cells, whether in a bruise or in your liver.
Biliverdin doesn’t stick around for long. A second enzyme converts it into bilirubin, which is yellow. That’s why the green stage of a bruise typically fades into a yellowish or brownish tone before disappearing entirely. The progression from dark heme (nearly black) to green biliverdin to yellow bilirubin is essentially a color-coded readout of your body’s cleanup machinery at work.
The Full Color Timeline
A typical bruise moves through a predictable sequence of colors over about two weeks:
- First few hours: Pinkish or red from fresh, oxygen-rich blood pooling under the skin.
- Days 1 to 3: Dark blue or purple as the hemoglobin loses oxygen and darkens.
- Days 5 to 7: Green as biliverdin accumulates from heme breakdown.
- Days 7 to 10: Yellow or dark yellow as biliverdin converts to bilirubin.
- Days 10 to 14: Pale yellow or light brown as the last pigments are absorbed and cleared.
These stages overlap, especially in larger bruises where different areas may be at different points in the healing process. You can sometimes see rings of color, with the edges turning green or yellow while the center is still purple. That’s because the outer edges, where blood spread thinnest, get broken down faster.
Why Some Bruises Stay Colorful Longer
Not every bruise follows the two-week playbook. Several factors can slow down the cleanup process or make bruises look more intense. Deeper bruises, for instance, take longer to heal because there’s simply more leaked blood for macrophages to process. A bruise on your shin may linger longer than one on your forearm because blood tends to pool in the lower legs under the influence of gravity.
Certain medications also play a role. Blood thinners, aspirin, and common painkillers like ibuprofen and naproxen all interfere with clotting or platelet function, which means more blood can leak from damaged vessels in the first place. The result is a bigger bruise that takes longer to cycle through each color stage. If you’re taking any of these and notice that bruises seem larger or more persistent, the medication is the likely explanation.
Age matters too. As skin thins and loses some of its fatty padding over the years, blood vessels have less cushion protecting them. Older adults tend to bruise more easily and may notice bruises lasting well past two weeks, spending more time in the green and yellow stages.
When a Bruise Signals Something Else
Most bruises are harmless and follow the color progression described above. A bruise that hasn’t healed within two weeks, however, is worth paying attention to. The same goes for frequent bruising that shows up without any clear cause, or bruising accompanied by unusual symptoms like muscle weakness, tingling, numbness, or changes in skin color that suggest circulation problems.
A bruise that feels firm, swollen, and increasingly painful rather than gradually fading may actually be a hematoma, a larger collection of clotted blood that sometimes needs medical attention. Clotting disorders, certain blood cancers, and liver conditions that impair your body’s ability to process bilirubin can all show up as abnormal bruising patterns.