Toenail fungus usually looks like a nail that becomes yellow, white, or brown, thicker than normal, and brittle. In early stages, it may appear as a small white or yellow spot on the nail. As the infection progresses, the nail can become crumbly, distorted, and sometimes emit an unpleasant odor.
Introduction
Toenail fungus is more common than many people realize — and often goes unnoticed in the beginning. Because early symptoms can look harmless, many people delay treatment until the infection becomes harder to manage.
Knowing what toenail fungus looks like in its early stages can help you act faster, prevent spreading, and choose the right treatment before the nail becomes severely damaged.
In this guide, you’ll see the most common visual signs, how they change over time, and when you should take action.
What Is Toenail Fungus?
Toenail fungus, also called onychomycosis, is a fungal infection that develops when fungi enter the nail through tiny cracks or separations between the nail and nail bed.
It thrives in warm, moist environments, which is why it often starts after:
- Wearing tight or sweaty shoes
- Walking barefoot in public showers or pools
- Nail injuries or pedicures with unsterilized tools
Once established, the fungus grows slowly — but it doesn’t go away on its own in most cases.
Early Signs of Toenail Fungus (Stage 1)
In the beginning, toenail fungus can be subtle and easy to miss.
Common early visual signs:
- Small white or yellow spot on the nail
- Slight discoloration near the tip or sides
- Nail looks dull instead of shiny
- Very mild thickening
At this stage, the nail usually:
- Does not hurt
- Does not smell
- Still looks mostly normal
👉 This is the best time to treat the infection effectively, including with at-home solutions.
(See: How to Treat Toenail Fungus at Home)
What Does Mild to Moderate Toenail Fungus Look Like? (Stage 2)
As the fungus spreads deeper, changes become more noticeable.
Visual symptoms include:
- Yellow, brown, or off-white discoloration
- Nail becomes thicker and harder to trim
- Edges may look uneven or rough
- Nail starts lifting slightly from the nail bed
Some people also notice:
- Increased nail brittleness
- Chalky residue under the nail
At this point, treatment is still very possible — but consistency becomes important.
What Does Severe Toenail Fungus Look Like? (Stage 3)
Advanced toenail fungus causes clear nail damage and discomfort.
Severe visual signs:
- Dark yellow, brown, or black discoloration
- Crumbling or breaking nail
- Nail deformity or twisted shape
- Partial or full nail separation
Some people experience:
- Mild pain or pressure in shoes
- Unpleasant odor
- Secondary infections if untreated
👉 In severe cases, stronger treatments may be required.
You can compare the most effective options here:
Best Toenail Fungus Treatments 2025
Different Types of Toenail Fungus (How They Look)
Not all toenail fungus looks the same.
White Superficial Fungus
- Powdery white patches on the nail surface
- Nail becomes rough and crumbly
- Often easier to treat if caught early
Distal Subungual Fungus (Most Common)
- Starts at the nail tip
- Yellow or brown discoloration
- Thickening and lifting over time
Proximal Subungual Fungus (Rare)
- Begins near the cuticle
- White spots near nail base
- May indicate immune issues
Toenail Fungus vs Normal Nail Changes
Not every nail problem is fungus.
Nail fungus usually:
- Spreads slowly over time
- Changes color and thickness
- Affects one nail first, then others
Normal nail changes:
- Grow out evenly
- Improve with trimming
- Don’t worsen progressively
If the nail keeps getting worse instead of growing out healthy, fungus is likely involved.
When Should You Start Treatment?
You should consider treatment if:
- Discoloration doesn’t grow out after weeks
- Nail becomes thicker or brittle
- Infection starts spreading to other nails
Early action prevents:
- Permanent nail damage
- Long treatment times
- Spread to other toes
Many people start with topical or natural approaches before moving to stronger options.
A full breakdown is available here:
👉 Best Toenail Fungus Treatments 2025
Can Toenail Fungus Spread to Other Nails?
Yes. Toenail fungus can spread:
- From one nail to another
- To fingernails
- To the skin (athlete’s foot)
That’s why early identification and hygiene are essential.
FAQs – Toenail Fungus Appearance
Most commonly yellow or white, but it can turn brown or even black in advanced cases.
Not at first. Thickening usually happens as the infection progresses.
Early stages usually don’t hurt. Pain may occur in advanced infections due to pressure.
It can in later stages, especially when debris builds under the nail.
Final Thoughts
Toenail fungus often starts small — but ignoring early visual signs can lead to long-term nail damage. Knowing what toenail fungus looks like helps you act before the infection becomes stubborn and difficult to treat.
The earlier you respond, the easier and faster recovery usually is.
Reviewed by Laura Collins
Editor & Lead Content Researcher at Nail Health Guide
Laura Collins reviews nail health content using a research-based approach focused on clarity, accuracy, and real-world relevance.
Learn more about Laura Collins