A fingernail that’s been completely lost takes about 6 months to grow back fully. A toenail takes much longer, typically 12 to 18 months. These timelines vary depending on your age, overall health, which finger or toe is affected, and even the time of year.
Fingernails vs. Toenails: The Basic Timelines
Fingernails grow at an average rate of 3.47 millimeters per month, roughly a tenth of a millimeter per day. Toenails grow at less than half that speed: about 1.62 millimeters per month. That difference is why a lost fingernail can be fully replaced in around 6 months, while a lost toenail can take up to 18 months. Big toenails, being the largest, sit at the longer end of that range.
If the nail was lost due to injury or trauma rather than a clean medical removal, regrowth tends to be even slower. Toenail regrowth after trauma can stretch anywhere from 6 months to 2 years, depending on how much damage the nail bed sustained.
What Regrowth Actually Looks Like
New nail growth starts at the nail matrix, a small pocket of tissue tucked just beneath the skin at the base of your nail. About 90% of nail production happens in this area. The matrix constantly generates new cells, which harden and flatten as they’re pushed forward, forming the visible nail plate. Each nail is made up of roughly 196 layers of these cells stacked together.
After a nail is lost, you won’t see anything happening for the first few weeks. Between weeks 3 and 5, a rough patch of new nail typically becomes visible just beyond the cuticle line. This new growth slowly advances toward the tip of the finger or toe, eventually pushing off any remnant of the old nail plate as it goes.
That first replacement nail usually looks rough, ridged, or uneven. It takes several full growth cycles, around 9 to 12 months for fingernails, before the nail returns to its normal smooth, shiny appearance. So even after your nail reaches full length, expect it to look a little different for a while.
Why Some Nails Grow Back Faster Than Others
Not all fingers grow nails at the same speed. Nails on your dominant hand tend to grow slightly faster, likely because that hand gets more blood flow from regular use. Your middle finger typically has the fastest-growing nail, while the pinky is the slowest. The same principle applies to toes: the big toe grows faster than the smaller ones, but all toenails lag behind fingernails.
Age plays a significant role. Nail growth peaks in early adulthood and gradually slows with age. Children’s nails grow faster than adults’, and older adults may find regrowth takes noticeably longer than the averages suggest.
Season and temperature also matter. Research published in the Journal of Applied Physiology found that nails grow measurably slower in cold environments compared to temperate ones. The likely explanation is that cold temperatures reduce blood circulation to the extremities, which limits the supply of nutrients reaching the nail matrix. If you lose a nail in winter, regrowth may be a bit slower than if the same thing happened in summer.
Nutrition and Health Conditions That Slow Regrowth
Your nails need a steady supply of protein, vitamins, and minerals to grow normally. Protein deficiency can make nails soft and thin, and in severe cases it disrupts growth enough to cause horizontal grooves (called Beau’s lines) across the nail plate. These grooves mark a period when growth essentially stalled. Low calcium levels can cause even more dramatic disruption, sometimes triggering the nail plate to separate from the nail bed entirely.
General malnutrition, vitamin deficiencies, and chronic conditions all affect how quickly a nail returns. Thyroid disorders can make nails brittle and prone to separating from the nail bed. Psoriasis can cause pitting, splitting, and long-term destruction of the nail plate. Kidney disease, liver disease, and circulatory problems all interfere with normal nail health. Chemotherapy is well known for disrupting nail growth, sometimes pausing it for the duration of treatment. Any severe illness or major surgery can temporarily slow growth enough to leave visible grooves in nails that were already growing at the time.
How to Support Healthy Regrowth
You can’t dramatically speed up nail growth, but you can avoid slowing it down. Eating enough protein is the single most important dietary factor, since nails are made almost entirely of a hardened protein called keratin. A balanced diet with adequate iron, zinc, and B vitamins supports normal production. Biotin supplements are widely marketed for nail growth, though evidence for their benefit is strongest in people who were already deficient.
Protecting the nail bed matters just as much as nutrition. If you’ve lost a nail to injury, keeping the exposed nail bed clean and covered during the early weeks reduces the chance of infection, which can damage the matrix and delay regrowth or cause the new nail to grow in irregularly. Avoid picking at or pulling on the emerging nail plate, even if it looks rough or uneven. Let it grow out on its own.
Keeping your hands and feet warm during cold months supports blood flow to the nail matrix. Regular physical activity helps for the same reason: better circulation means more consistent nutrient delivery to the tissues that build your nails.
When Regrowth Doesn’t Go as Expected
Most nails grow back without complications, but the process isn’t always smooth. If the nail matrix was significantly damaged during the original injury, the new nail may grow back permanently thickened, ridged, split, or discolored. In some cases, a badly scarred matrix produces a nail that’s cosmetically different but functionally fine.
If several months have passed and you see no new growth at all, or if the new nail is growing in a painful or severely abnormal way, the matrix itself may have been damaged beyond its ability to regenerate normally. Nails that repeatedly fall off or never seem to fully attach to the nail bed can signal an underlying issue like a fungal infection, psoriasis, or circulation problems that are worth investigating.