KFRE Calculator

A urine albumin-to-creatinine ratio (UACR) under 30 mg/g (under 3 mg/mmol) is normal. Higher numbers mean albumin is leaking into your urine, which is a sign of kidney damage.

• A1: under 30 mg/g, normal to mildly raised
• A2: 30 to 300 mg/g, moderately raised
• A3: over 300 mg/g, severely raised

UACR is a strong warning sign. Two people can have the same eGFR, but the one with a higher UACR has a much higher chance of kidney failure.

You pee into a cup, and the lab measures two things in that one sample: albumin and creatinine. Dividing one by the other gives the ratio. You do not need to collect urine for 24 hours.

The first pee of the morning gives the best result. Hard exercise, fever, an infection, or your period can raise the number for a short time. Because of this, doctors usually confirm a high result with a second test a few weeks later.

There is no single number. Most people start dialysis when eGFR falls below 10 mL/min/1.73m², and sometimes below 15 if they feel sick.

Symptoms matter more than the number alone. Signs it may be time include bad nausea, swelling that will not go away, trouble breathing, high potassium, or feeling very tired and confused. Some people sit at an eGFR of 12 for years and feel fine.

No. The score is a chance, not a promise. A 5-year risk of 30% means about 30 out of 100 similar people reach kidney failure in 5 years. The other 70 do not.

The score also assumes nothing changes. Starting treatments like SGLT2 inhibitors, ACE inhibitors or ARBs, and better blood pressure control can cut that risk a lot. A high score is a reason to act early, not a reason to give up.

It depends on the person. As a rough guide, healthy kidneys lose about 1 mL/min of eGFR per year after age 40. Many people with stable CKD lose about the same, so they never reach kidney failure.

CKD moves faster when there is high protein in the urine, uncontrolled diabetes, high blood pressure, or repeated kidney injuries. Those people can lose 4 to 10 mL/min per year. Protein in the urine is the biggest warning sign of fast loss.

Scarred kidney tissue does not grow back, so CKD usually cannot be reversed. But it can often be slowed down a lot, and sometimes eGFR goes up a little once blood pressure, blood sugar, and urine protein are under control.

The biggest wins are controlling blood pressure, taking an ACE inhibitor or ARB, adding an SGLT2 inhibitor, cutting salt, quitting smoking, and avoiding NSAID pain pills like ibuprofen.

Damaged kidneys stop balancing minerals and acid in the blood. These four labs show how much that balance has slipped:

• Phosphorus builds up when kidneys cannot clear it. High levels harm bones and blood vessels.
• Bicarbonate drops when acid builds up. Low levels speed up kidney loss and weaken muscle.
• Calcium falls out of balance with phosphorus and vitamin D.
• Albumin drops with poor nutrition or heavy protein loss in urine.

Abnormal values point to more advanced disease, which is why the 8-variable KFRE is a bit sharper than the 4-variable one.

The 2009 CKD-EPI equation included a race factor that raised eGFR for Black patients. The 2021 version removed it, because race is a social label, not a biological measure of kidney function.

Without the race factor, the 2021 equation gives slightly lower eGFR values for Black patients and slightly higher values for others. Most labs in the United States now report the 2021 version. The KFRE itself was built and validated using eGFR from the 2009 equation.

Because younger people have more years for the disease to progress, and a low eGFR at a young age usually means a more aggressive disease.

In older adults, a mildly low eGFR is often just normal aging. They are also more likely to die of something else, like heart disease, before their kidneys fail. That is why age lowers the KFRE score, even though older people are more likely to have CKD.

At least once a year for everyone with CKD. People at higher risk need them more often.

• Low risk: once a year
• Moderate risk: once or twice a year
• High risk: two times a year
• Very high risk: three or four times a year

Always check both tests together. eGFR alone misses people who have heavy protein loss but decent filtering.

Not really. Drinking extra water does not repair kidneys or raise eGFR in any lasting way, and it has not been shown to slow kidney loss in people with CKD.

What does matter is not getting dehydrated. Being very dry raises creatinine and drops eGFR for a short time, so a lab drawn while you are dehydrated can look worse than your true level. Drink when thirsty unless your doctor limits your fluids.

Chronic kidney disease means your kidneys are damaged or filtering less well for at least 3 months. Most people with CKD feel fine and never get worse.

Kidney failure, also called end-stage kidney disease, means the kidneys have stopped working well enough to keep you alive without help. At that point a person needs dialysis or a transplant. This is the exact event the KFRE predicts.

A few simple changes help most people with CKD:

• Cut salt to under 2,300 mg a day. This lowers blood pressure and urine protein.
• Skip phosphate additives in processed food, soda, and deli meat. Look for ingredients with "phos" in the name.
• Eat less animal protein and more plants, beans, fruit, and vegetables.
• Limit potassium only if your blood potassium is high. Not everyone needs to.

Ask for a kidney dietitian. Food rules change as CKD advances, so general advice may not fit your stage.