UPCR Calculator

Q: What does a protein-to-creatinine ratio of 0.3 mean in pregnancy?

A ratio of 0.3 mg/mg (300 mg/g) or higher is the common cut-off used to confirm significant protein in urine during pregnancy. ACOG's 2013 preeclampsia criteria list a protein:creatinine ratio of 0.3 or more, or at least 300 mg of protein in a 24-hour urine collection. 7 When it happens after 20 weeks along with high blood pressure, doctors think about preeclampsia. Preeclampsia can be dangerous for mother and baby, so any pregnant person with a high ratio needs to be checked by a doctor right away.

Q: How do you convert mg/g to mg/mmol for a protein-creatinine ratio?

Divide the mg/g number by 8.84 to get mg/mmol. To go the other way, multiply mg/mmol by 8.84. Example: 150 mg/g ÷ 8.84 = about 17 mg/mmol . The number 8.84 comes from the weight of one mmol of creatinine, which is 113.12 mg.

Q: What does 1+ protein on a urine dipstick mean?

A 1+ dipstick reading corresponds to roughly 30 mg/dL of protein in a random urine sample. 7 It is a rough screen, not a measurement. Dipsticks react to how concentrated the urine is, so dilute urine can hide protein and concentrated urine can fake a high reading. A positive dipstick is usually followed by a protein-to-creatinine ratio test to get a real number. 2

Introduction

The UPCR Calculator finds your urine protein-to-creatinine ratio. This ratio shows how much protein is leaking into your urine. Healthy kidneys keep protein in the blood. When protein shows up in urine, it can be an early sign of kidney damage.²

To use it, you need two numbers from a spot urine test: urine protein and urine creatinine. The tool divides protein by creatinine and gives you the result in mg/g, mg/mg, and mg/mmol. It also estimates how much protein you would lose in 24 hours, so you can skip the all-day urine collection.

Your result is sorted into simple ranges:

Under 150 mg/g: normal protein in urine
150 to 500 mg/g: mild to moderate proteinuria¹
500 to 3,500 mg/g: sub-nephrotic range
Over 3,500 mg/g: nephrotic range.⁶ This needs fast medical care.

You can also mark if you have Type 1 diabetes. The tool then adds notes that fit your case, since diabetes raises the risk of kidney disease.

A first-morning urine sample is preferred.² This calculator is a learning tool. Always talk to your doctor about what your numbers mean.

How to use our UPCR Calculator

Enter your urine protein and urine creatinine lab values, pick their units, and tell us if you have Type 1 diabetes. The UPCR Calculator then shows your urine protein-to-creatinine ratio in mg/g, mg/mg, and mg/mmol, your estimated 24-hour protein loss, a risk zone, and a step-by-step solution.

Urine Protein: Type the protein amount from your urine test, then choose the unit on your lab report (mg/dL, mg/L, g/L, or g/dL). A first-morning, midstream sample is preferred, and a random spot sample can also be used.²

Urine Creatinine: Type the creatinine amount from the same urine sample, then choose its unit (mg/dL, µmol/L, or mmol/L). This value cannot be zero, since it is used to divide the protein value.

Does the patient have Type 1 Diabetes? Pick "Yes" or "No." Choosing "Yes" adds an extra note about diabetic kidney disease to your result.

Calculate, Reset, and Load Sample Data: Press "Calculate" to see your UPCR result, "Reset" to clear all fields, or "Load Sample Data" to fill the form with example lab values.

What Is the Urine Protein-to-Creatinine Ratio (UPCR)?

The urine protein-to-creatinine ratio, or UPCR, compares how much protein is in your urine to how much creatinine is in it. Creatinine is a waste product your muscles make every day at a steady rate. Because that rate stays steady, creatinine works like a built-in measuring stick. It tells you how watery or how strong a urine sample is, so the protein number can be trusted.

Why Protein in Urine Matters

Healthy kidneys act like tiny filters. They keep protein in your blood and let waste pass into your urine. When the filters get damaged, protein leaks out. Doctors call this proteinuria. It is one of the earliest signs of kidney disease, and it can also point to high blood pressure, diabetes, infection, or heart problems.³ Finding it early gives you more time to slow the damage down.

What the Numbers Mean

UPCR is usually reported in milligrams of protein per gram of creatinine (mg/g). A handy fact: the ratio in mg/mg roughly matches the grams of protein you would lose in a full 24-hour period.¹

Under 150 mg/g: normal.¹ Very little protein is leaking.
150 to 500 mg/g: mild to moderate.¹ Worth watching and checking the cause.
500 to 3,500 mg/g: sub-nephrotic. This is a real warning sign and needs follow-up.
Over 3,500 mg/g: nephrotic range.⁶ This needs fast medical attention.

Spot Urine vs. 24-Hour Collection

The old way to measure protein loss was to save all your urine for a whole day. That is messy, slow, and easy to mess up. A spot sample is one quick cup of urine. Because creatinine output is fairly steady, the ratio from that one cup gives an estimate of the 24-hour result, though creatinine output varies with age, sex and diet.¹ It is faster, cheaper, and easier to repeat over time.

Why a First-Morning Sample Is Preferred

KDIGO guidelines prefer a first-morning, midstream urine sample for protein and albumin tests.² Some people leak protein only when they are upright, which is called orthostatic proteinuria. A first-morning sample taken after a night lying down helps rule this out.¹

Protein Units You May See

Labs report results in different units, like mg/dL, mg/L, g/L, µmol/L, or mmol/L. They all describe the same thing, just on different scales. Converting them to the same unit before dividing is what keeps the ratio accurate. Outside the United States, UPCR is often written in mg/mmol instead of mg/g.

Diabetes and Kidney Screening

People with type 1 diabetes face a higher risk of kidney damage, and it often starts quietly. For them, even small rises in urine protein matter. KDIGO guidelines list the urine albumin-to-creatinine ratio as the first choice for testing, ahead of the protein-to-creatinine ratio.¹

Things That Can Change Your Result

Hard exercise before the test
A urinary infection
Menstrual blood or other blood in the sample
Very high or very low body weight or muscle mass²
Fever¹
Being dehydrated³

Because of these, one high result does not mean kidney disease. Doctors usually repeat the test before making a call.² Always go over your results with a healthcare provider, who can look at your full history, blood tests, and blood pressure together.

Formulas used

Urine protein normalized to mg/dL

P_{mg/dL} = P_{input} \times f_P, \quad f_P = \begin{cases} 1 & \text{mg/dL} \\ 0.1 & \text{mg/L} \\ 100 & \text{g/L} \\ 1000 & \text{g/dL} \end{cases}

Urine creatinine normalized to mg/dL

C_{mg/dL} = C_{input} \times f_C, \quad f_C = \begin{cases} 1 & \text{mg/dL} \\ 0.011312 & \mu\text{mol/L} \\ 11.312 & \text{mmol/L} \end{cases}

UPCR in mg/mg (base ratio)

UPCR_{mg/mg} = \frac{P_{mg/dL}}{C_{mg/dL}}

UPCR in mg/g (primary result)

UPCR_{mg/g} = UPCR_{mg/mg} \times 1000

UPCR in SI units (mg/mmol)

UPCR_{mg/mmol} = UPCR_{mg/mg} \times 113.12

Estimated 24-hour protein excretion ¹

\text{Protein}_{24h}\ (\text{g/day}) \approx UPCR_{mg/mg}

Risk scale marker position

\text{Position}\ (\%) = \min\!\left(\frac{UPCR_{mg/g}}{1000},\ 1\right) \times 100

Frequently asked questions

What is the difference between UPCR and urine albumin-to-creatinine ratio (ACR)?

Both tests compare a protein in urine to creatinine, but they measure different things.

UPCR measures total protein, which includes albumin plus many other proteins.
ACR measures only albumin, the protein that leaks out first when kidney filters start to fail.

ACR is better for early screening, especially in people with diabetes or high blood pressure.¹ UPCR is often used when protein loss is already high or when doctors suspect kidney problems that leak proteins other than albumin.

What does a protein-to-creatinine ratio of 0.3 mean in pregnancy?

A ratio of 0.3 mg/mg (300 mg/g) or higher is the common cut-off used to confirm significant protein in urine during pregnancy. ACOG's 2013 preeclampsia criteria list a protein:creatinine ratio of 0.3 or more, or at least 300 mg of protein in a 24-hour urine collection.⁷ When it happens after 20 weeks along with high blood pressure, doctors think about preeclampsia.

Preeclampsia can be dangerous for mother and baby, so any pregnant person with a high ratio needs to be checked by a doctor right away.

What are the signs of protein in your urine?

Small amounts cause no symptoms at all. That is why testing matters. When protein loss gets large, you may notice:

Foamy urine
Swelling in the face and around the eyes, in the arms and legs (especially the feet and ankles), or in the belly
Weight gain from held-in fluid
Poor appetite⁵

Swelling plus foamy urine can point to heavy protein loss and needs a medical check.

How do you convert mg/g to mg/mmol for a protein-creatinine ratio?

Divide the mg/g number by 8.84 to get mg/mmol. To go the other way, multiply mg/mmol by 8.84.

Example: 150 mg/g ÷ 8.84 = about 17 mg/mmol.

The number 8.84 comes from the weight of one mmol of creatinine, which is 113.12 mg.

What is a normal urine creatinine level in a spot urine sample?

Spot samples are typically between 80 and 150 mg/dL and can range from about 20 to 300 mg/dL.⁴ Men usually have higher urine creatinine than women.²

A very low number usually means the urine is watery and dilute. A very high number means it is concentrated. Both can throw off a protein reading, which is exactly why the protein number is divided by creatinine.

How can I lower the protein in my urine?

The main goal is to treat what is causing the leak. Common steps doctors use:

Control blood pressure, often with an ACE inhibitor or ARB, which also cuts protein loss directly
Keep blood sugar in range if you have diabetes
SGLT2 inhibitor medicines for many people with chronic kidney disease
Eat less salt
Stop smoking and keep a healthy weight²

Never start or stop a kidney or blood pressure medicine on your own. Ask your doctor first.

Can dehydration cause protein in your urine?

Dehydration makes urine more concentrated, so a plain protein reading can look high. But the protein-to-creatinine ratio mostly cancels this out, because creatinine gets concentrated too.

Still, being very dry or drinking huge amounts of water right before the test can shift the result a little. Drink normally on test day for the truest picture.

Does eating a lot of protein cause protein in your urine?

A high-protein meal or shake does not directly put protein into your urine if your kidneys are healthy. Healthy filters hold protein back no matter how much you eat.

However, a big protein load makes the kidneys work harder. People who already have kidney damage are often told to keep protein intake moderate to slow the damage down.²

What is orthostatic proteinuria?

It means protein leaks into urine when a person is upright but not when lying down. It is seen in about 2% to 5% of teenagers and is not linked to long-term harm.¹

Doctors check for it with a first-morning sample taken after lying down all night.¹ If the morning sample is clean and a daytime one has protein, that points to orthostatic proteinuria.

What does 1+ protein on a urine dipstick mean?

A 1+ dipstick reading corresponds to roughly 30 mg/dL of protein in a random urine sample.⁷ It is a rough screen, not a measurement.

Dipsticks react to how concentrated the urine is, so dilute urine can hide protein and concentrated urine can fake a high reading. A positive dipstick is usually followed by a protein-to-creatinine ratio test to get a real number.²

Do you need to fast before a urine protein test?

No. Fasting is not needed for a spot urine protein and creatinine test.

A few things do help: avoid hard exercise before the test, skip the test during your period if possible, and wait until any urinary infection has cleared.² Also let your doctor know about supplements like creatine, which can raise creatinine.

How often should protein in urine be checked?

It depends on your risk. People with diabetes or high blood pressure should be tested with a urine albumin test and eGFR.² For people with chronic kidney disease, the KDIGO guideline suggests testing from once a year at the lowest-risk stages up to four or more times a year at the highest.² One raised result should be repeated to confirm it.²

A raised result that goes away within 3 months is not chronic kidney disease; one that persists points to lasting kidney damage.¹

Can protein in urine go away on its own?

Yes, sometimes. Protein caused by fever, an infection, hard exercise, stress, or standing a long time often clears once the cause passes. This is called temporary, or transient, proteinuria.¹

Protein that keeps showing up over months usually means the kidney filters are damaged. That kind does not go away on its own, but treatment can lower it and slow further harm.

Sources

Kidney Disease: Improving Global Outcomes (KDIGO) CKD Work Group. KDIGO 2012 Clinical Practice Guideline for the Evaluation and Management of Chronic Kidney Disease. Kidney International Supplements. 2013;3(1):1-150; Table 7. Accessed September 26, 2026.

Kidney Disease: Improving Global Outcomes (KDIGO) CKD Work Group. KDIGO 2024 Clinical Practice Guideline for the Evaluation and Management of Chronic Kidney Disease. Kidney International. 2024;105(4S):S117-S314. doi:10.1016/j.kint.2023.10.018. Accessed September 26, 2026.

Urine protein dipstick test. MedlinePlus, U.S. National Library of Medicine. Accessed September 26, 2026.

LAB384 - UCSF Clinical Laboratories Test Directory. UCSF Clinical Laboratories. Accessed September 26, 2026.

Nephrotic syndrome. MedlinePlus, U.S. National Library of Medicine. Accessed September 26, 2026.

Kidney Disease: Improving Global Outcomes (KDIGO) CKD Work Group. Chapter 1: Definition and classification of CKD. Kidney International Supplements. 2013;3(1):19-62 (Albuminuria categories: nephrotic range). doi:10.1038/kisup.2012.64. Accessed October 7, 2026.

Appendix C, Preeclampsia Diagnostic Criteria Included in Major Guidelines and Recommendations, 1972-2013. Screening for Preeclampsia: A Systematic Evidence Review for the U.S. Preventive Services Task Force. Agency for Healthcare Research and Quality. 2017;Appendix C. Accessed October 8, 2026.