That Dark Toenail Is Telling You Something

Quick summary

• A bruised toenail is a subungual haematoma: blood pooling beneath the nail plate after trauma or repetitive pressure.
• Colour ranges from red and purple through to dark blue and black depending on age and severity.
• Healing takes 6 to 12 months because the discolouration grows out with the nail, not fades in place.
• A badly bruised toenail may cause the nail to separate and fall off. A new nail will grow back.
• Not every dark toenail is a bruise. Fungal infection and, rarely, melanoma can look similar.
• Severe bruising with significant pain requires podiatry assessment to drain the haematoma safely.

What Is a Bruised Toenail (Subungual Haematoma)?

The clinical term is subungual haematoma. The everyday term is a bruised toenail. Both describe the same thing: blood that has pooled between the nail plate and the nail bed after the small blood vessels beneath the nail are damaged by trauma.

The blood becomes trapped because there is nowhere for it to drain. As it collects, pressure builds under the nail, which is what causes the characteristic throbbing pain. Over time, the blood oxidises and darkens, producing the deep red, purple, or black discolouration most people associate with a bruised toenail.

The toenail itself is not damaged in the way skin is. It doesn't bruise the way a muscle does. What you are seeing is blood pooled in the sealed space beneath the nail, with the nail plate itself acting as a rigid cap that prevents natural drainage.

Key fact: Unlike a bruise on skin, a bruised toenail does not fade over days or weeks. The discolouration is locked beneath the nail plate and only disappears once the nail grows forward enough to carry it off the end of the toe. Depending on the size of the haematoma, this can take anywhere from 3 to 12 months.

What Does It Look Like? Reading the Colours

One of the questions people ask most is whether the colour of their bruised toenail tells them anything. It does. The shade you see under the nail reflects the age of the blood and, to a degree, the severity of the bleed.

Bruising underneath the toenail most commonly affects the big toenail, simply because it is the largest and most exposed to impact and shoe pressure. However, bruising in toenails on the second and third toes is also frequently seen, particularly in runners and people who wear narrow or short footwear.

What Causes Bruising Under the Toenail?

The root cause is always some form of force applied to the toe. The circumstances in which that force occurs vary considerably.

• Acute Trauma: Dropping a heavy object onto the foot. Stubbing a toe hard against furniture, a doorframe, or the ground. Being stepped on. These are the most obvious causes and tend to produce immediate, intense pain followed by visible bleeding beneath the nail within minutes to hours. The haematoma is usually large when caused by acute trauma and may rapidly turn dark purple or black.
• Repetitive Pressure and Footwear: This is actually the more common cause, particularly among people who are physically active. When shoes are too short, too narrow, or lack adequate toe box volume, the toes are repeatedly pushed forward with every step, pressing the nail against the shoe. Over thousands of steps, this cumulative micro-trauma causes bruising under the toenail that builds gradually, often without any single obvious incident. Shoes with a heel that pitches the foot forward (dress shoes, court shoes, high heels) are especially problematic because they increase the load on the toes during every walking cycle. Ill-fitting footwear during sport, where foot volume increases with swelling, compounds this further.
• Nail Length: A toenail that is too long has more surface area to catch on the shoe during activity. Each catch drives the nail back into the nail bed, creating micro-bleeding that accumulates over time. Keeping toenails trimmed to just beyond the tip of the toe is one of the most effective prevention strategies — but trimming them too short creates a different set of problems, including ingrown toenails.
• Activity Type and Terrain: Downhill running is particularly hard on toenails because the foot slides forward in the shoe with each downhill stride, driving the toes into the front of the shoe. Stop-start sports where the foot decelerates rapidly within the shoe — tennis, basketball, netball, squash — produce similar effects. Hiking on steep descents is another common setting for bruising toenails, particularly on the big toe.

Runner's Toe and Sport-Related Toenail Bruising

"Runner's toe" is the informal name given to a bruised toenail from running, particularly from distance running, trail running, or any running that involves sustained downhill grades. It's one of the most common complaints among recreational runners and is almost always preventable.

• Running and Trail Running: Downhill stride mechanics drive the foot forward repeatedly. The second toe is often the worst affected in runners because it frequently extends further than the big toe.
• Hiking and Trekking: Long descents on uneven terrain create sustained toe-to-shoe contact. Poor lacing technique that allows the foot to slide is a major contributing factor.
• Court Sports: Rapid deceleration and direction changes in tennis, squash, netball, and basketball repeatedly push the foot into the front of the shoe. Bruising toenails is common in players who compete frequently.
• Football and Field Sports: Kicking a ball — especially with the toe-box — can cause acute bruising on the toenail bed of the big toe. Studs that don't flex adequately also add rigid pressure during running.
• Dance (especially ballet): Pointe work concentrates enormous pressure on the tips of the toes and the nail beds. Bruised toenails are considered an occupational reality in classical ballet.
• Rock Climbing: Tight, aggressive climbing shoes press the toes into a cramped position. Sustained pressure on small footholds concentrates force directly under the nail bed, causing bruising over time.

Running with a bruised toenail is possible in mild cases with adequate cushioning and the right shoe fit, but should be assessed by a podiatrist first if the bruise covers more than a quarter of the nail, is throbbing, or has caused the nail to feel loose.

Bruised Toenail or Melanoma? How to Tell the Difference

This is one of the questions podiatrists are asked most when a dark toenail appears without a clear injury history. It is a legitimate concern, not an overreaction. Subungual melanoma is a form of skin cancer that develops beneath the nail and can look, at a glance, like a bruised toenail — particularly in its early stages.

This does not mean every dark toenail is suspicious. The vast majority of discoloured nails are caused by trauma. But the distinction matters, and the comparison below gives you a useful framework.

• Cause: Bruised toenail: Clear trauma or repetitive pressure history. Subungual melanoma: No injury history in most cases.
• Appearance: Bruised toenail: Diffuse blotch of dark red, purple or black beneath the nail. Subungual melanoma: Brown or black vertical streak (band) running from nail base to tip.
• Movement: Bruised toenail: Moves forward as the nail grows (grows out over months). Subungual melanoma: Does not move with nail growth; stays fixed at the base.
• Skin involvement: Bruised toenail: Confined under the nail plate only. Subungual melanoma: May extend onto the skin around the nail (Hutchinson's sign).
• Pain: Bruised toenail: Often present and corresponds to the injury event. Subungual melanoma: Often painless, especially early on.
• Edges: Bruised toenail: Irregular, smudged, colour may vary within the blotch. Subungual melanoma: Streak with relatively defined edges; width may vary.
• Who to see: Bruised toenail: Podiatrist for assessment and treatment if significant. Subungual melanoma: Podiatrist or dermatologist urgently for biopsy.

The rule — when in doubt, get it checked: If you have a dark toenail and you cannot clearly link it to an injury or sporting activity, see a podiatrist or GP. Subungual melanoma is rare, but it is far more treatable when caught early. A podiatrist can assess the nail in clinical context and refer appropriately if anything is suspicious. Never self-diagnose a dark toenail you cannot explain.

Bruised Toenail or Fungus? Another Common Confusion

Fungal nail infection (onychomycosis) is far more common than melanoma and, in some presentations, can look similar to an old or mild bruised toenail. Both can produce a dark, discoloured, thickened nail. The key differences:

• A bruised toenail typically produces a distinct area of purple, blue-black, or black discolouration with relatively clear borders. The nail texture may remain normal initially, and the nail often grows forward carrying the discolouration with it.
• A fungal nail tends to start at the tip or sides of the nail and progress inward. The nail often thickens, becomes brittle and crumbly, and may develop a yellow or brown, powdery discolouration rather than the dark pooled blood colour of a haematoma. There is typically no trauma history.
• A nail can also have both conditions simultaneously: trauma can create a nail that lifts slightly, creating an entry point for fungal infection to establish underneath.

Bruise on toenail or fungus: if you have any doubt, a podiatrist can usually make a clinical diagnosis from physical examination. Where necessary, a nail clipping can be sent for laboratory analysis to confirm whether fungal organisms are present.

The Healing Timeline: How Long Does It Take?

This is where most people are caught off guard. A bruised toenail does not heal in the same way a bruised muscle heals. The blood cannot be reabsorbed beneath the nail plate, so the discolouration does not gradually fade over days or weeks. Instead, it stays locked in place until the nail grows forward enough to carry it off the end of the toe.

• Days 1 to 3 — Acute phase: Pain and throbbing are at their worst as blood pools and pressure builds under the nail. The discolouration darkens rapidly from red to deep purple or black. If the haematoma is large, the nail may feel loose.
• Week 1 to 4 — Pressure settles: Throbbing reduces as the pooled blood stabilises. The nail remains darkly discoloured. The nail may start to separate from the nail bed if the bruise covers a significant area. There should be no pain at this point unless infection is present.
• Month 1 to 6 — The nail grows forward: The discoloured portion of nail moves forward with normal nail growth. A new, healthy nail is growing from the base. If the nail separated, it may fall off during this period — a new nail is underneath. Regrowth may initially appear thickened or ridged.
• Month 6 to 12 — Full resolution: The bruised portion has grown off the end of the toe. A new nail has grown through to replace it. The bruised toenail healing process is complete. For a badly bruised toenail covering the entire nail bed, expect closer to 12 months.

Bruised toenail no pain: is that normal?

Yes. Once the acute pressure phase settles (usually within the first week), a bruised toenail should not be significantly painful. A bruised toenail with no pain and no signs of nail separation or infection can generally be left to resolve on its own. Pain that returns or worsens after the first week, or discharge appearing around the nail, warrants assessment.

What to Do at Home (and What to Avoid)

For a mild to moderate bruised toenail, conservative home management is appropriate. For a large, severely painful, or rapidly expanding haematoma, see a podiatrist promptly.

Safe at home

• Ice immediately after injury: Apply an ice pack wrapped in a cloth for 15 to 20 minutes as soon as possible after the trauma. This can reduce the volume of bleeding and limit the size of the haematoma.
• Elevation: Elevate the foot above heart level in the first few hours to reduce blood pressure to the area and limit pooling.
• Footwear modification: Switch immediately to open footwear or shoes with a deep, wide toe box that do not press on the bruised nail. Continued pressure on an active haematoma worsens pain and slows healing.
• Pain relief: Over-the-counter analgesia (paracetamol or ibuprofen if appropriate for you) can manage the throbbing pain in the acute phase.
• Protection: A gel toe protector or silicone toe cap from the pharmacy cushions the bruised toenail and prevents further trauma during activity.
• Keep the area clean: If the nail is loose or lifting, keep the area clean and dry to prevent bacterial entry. Do not pull a loose nail off.

What not to do

• Do not drain it yourself: Online advice recommends heating a needle and drilling through the nail to release pressure. While this is a clinical procedure a podiatrist can perform safely, attempting it at home risks serious infection and permanent nail damage. Never attempt this yourself.
• Do not pull off a loose nail: If the nail has separated, resist the urge to remove it. The nail is still protecting the raw nail bed underneath. Premature removal exposes the bed to infection and can be extremely painful. Let it separate naturally or have it managed by a podiatrist.
• Do not ignore spreading redness or warmth: These are signs of infection. A bruised toenail that becomes infected requires prompt medical treatment, potentially including antibiotics.
• Do not ignore a dark toenail with no clear cause: If you cannot explain your bruised toenail with a specific injury or activity, get it assessed rather than waiting for it to "grow out."

When and How a Podiatrist Treats a Bruised Toenail

Most mild bruised toenails resolve without professional intervention. But there are clear situations where a podiatrist can make a material difference — either by relieving pain immediately, preventing complications, or ruling out a more serious diagnosis.

• Trephination (Nail Decompression): When a haematoma is large, freshly formed, and causing significant throbbing pain, a podiatrist can perform a procedure called trephination — creating a small, precise opening through the nail plate to allow the trapped blood to drain. This is done under sterile conditions using a fine instrument and provides rapid, often dramatic, relief of pressure and pain. The nail is not removed. The small opening closes over as the nail grows. Done correctly, trephination is one of the most immediately effective pain-relief procedures in podiatry — and far safer than any home alternative. Trephination is most effective when performed within 24 to 48 hours of injury, while the haematoma is still fluid. After this window, the blood starts to clot and solidify, making drainage less effective.
• Nail Removal (Where Needed): In cases where the nail has significantly separated from the nail bed, is causing ongoing pain, or poses a risk of ingrowth as it grows back, a podiatrist may recommend partial or full nail removal under local anaesthetic. This is a straightforward in-clinic procedure and allows the nail bed to be examined, cleaned, and properly dressed. A new nail will grow back over the following months.
• Infection Treatment: If infection has developed around a bruised toenail — redness spreading from the nail, warmth, discharge, or increasing pain after the first week — your podiatrist will assess the severity and coordinate antibiotic treatment with your GP if required, alongside wound care and nail management.
• Footwear and Biomechanical Assessment: For runners, athletes, and anyone with recurrent bruising in toenails from activity, a podiatrist will assess not just the nail itself but the mechanical factors driving the problem. This includes gait analysis, footwear review, nail length guidance, and where appropriate, custom orthotic therapy to modify the load distribution through the forefoot during activity.

Bulk billed at Penrith Podiatry Clinic: If you hold a Chronic Disease Management (CDM) or Enhanced Primary Care (EPC) care plan from your GP, all podiatry visits at Penrith Podiatry Foot and Ankle Clinic are bulk billed. Call us on 1300 470 220 to check your eligibility before booking.