Split nails may happen due to nail biting, excess moisture, infection or injury, or psoriasis. You can’t always prevent split nails, but using moisturizer and nail hardening products may help.

Cracks in your nails are common and will usually heal as your nails grow. A split nail is typically caused by physical stress, nutrient deficiency, or wear and tear.

Split nails, also called onychoschizia, can be a problem, especially if you work with your hands.

Although split nails can happen to anyone and are sometimes unavoidable, there are ways you can prevent them.

Here we explain what might be the cause of your split nails, how to prevent them, and when to see a doctor.

Your fingernails and toenails are made out of layers of keratin, which is also the protein that hair is made out of.

Your nail protects the nail bed. The nail growth comes from below the cuticle area.

Healthy nails appear smooth, with consistent coloring. If you’re concerned with any changes to your nails, reach out to a doctor.

Learn more about your nail matrix and its anatomy.

A split nail is characterized by a crack forming in your nail. Nail splits can be horizontal, across the nail’s tip, or vertical, splitting the nail in two.

Common causes of split nails include:

Moisture

Moisture can cause nails to become weak and brittle. Long-term exposure can cause the skin around the nail to soften.

The nail itself becomes brittle, making it easier to break, bend, or split. Overexposure to moisture can occur while doing dishes, washing hands, or repeated nail polish use.

Picking or biting

Many people have a habit of picking their fingernails and toenails. Picking or biting is usually a result of anxiety or nervousness.

Picking or biting your nails can cause stress to the nail and result in a self-inflicted split or broken nail.

Injury

An injury is a likely cause of a split nail. Crushing your nail tip or bed can result in your nail growing with a ridge or split-like appearance.

Injury and weakening can also happen with fake nails.

Infections

Fungal, bacterial, or yeast infections in the nail bed can change the texture of the nails, resulting in weakened and split nails.

Psoriasis

Psoriasis can affect both the skin and the nails.

Psoriasis can cause nails to thicken, crumble, or split. About 40–50% of people with psoriasis are believed to experience nail symptoms.

Diseases

Certain diseases may also cause nail health to decline, which could contribute to nail splits.

Diseases that may contribute to nail problems include:

If your nail split is more severe, cover the nail with petroleum jelly and place a bandage on top until it grows back. Soak the nail in saline water 2–3 times a day and reapply the bandage.

If your nail split extends into your nail bed, you may need to visit a doctor. Your nail may have to be removed, and your nail bed may need stitches.

If your nail can be reattached, a doctor will reattach it with glue or stitches.

If you’re experiencing any of the following symptoms, be sure to contact a doctor:

How do you treat a split nail?

While there’s not much that you can do to fix a split nail, there are ways you can prevent your nails from splitting in the first place.

Here are some tips for preventing split nails:

  • Keep your nails clean and healthy.
  • If you do a manicure, perform it gently and avoid scraping the nail bed with metal.
  • Refrain from keeping your hands or feet in water for long periods.
  • Use a moisturizer on your nails and cuticles.
  • Use nail hardening products if necessary.
  • Don’t bite or pick around your nails.
  • Refrain from using acetone-based nail polish remover.
  • Wear gloves while doing household chores.
  • Don’t rip or pull your hangnails.

What causes vertical split nails?

Whether vertical or horizontal, split nails can be caused by things like infections, injuries, moisture, or skin conditions like psoriasis.

What vitamin is lacking when nails split?

The most common vitamin deficiencies that can lead to split nails are:

Most split nails will heal with time as your nails grow out. If you’re experiencing frequent splitting, avoid too much moisture on your nails and consider using a nail-hardening solution.

If your split nails are causing you frequent discomfort, reach out to a doctor about treatment options.