CKD Stage Chart
A CKD stage chart can make kidney results easier to read, but it can also make a report feel more alarming than it needs to be. The stage is a way to describe estimated kidney filtering. It is not the whole story, and one eGFR result does not by itself prove chronic kidney disease.
Overview
CKD staging usually starts with eGFR, the estimated glomerular filtration rate. eGFR is reported in mL/min/1.73 m2 and is commonly calculated from serum creatinine. KDIGO 2024 also recommends using creatinine together with cystatin C when that is available, because the combined estimate can be more accurate than creatinine alone.
The key word in chronic kidney disease is chronic. CKD requires kidney abnormality for at least 3 months. That abnormality can be eGFR below 60 or another marker of kidney damage, such as albumin in the urine. A chart helps label the eGFR range, but your doctor still has to interpret why the number is there and whether it persists.
CKD Stage Chart By eGFR
Use this chart as a reading aid, then compare it with the range and notes printed on your own lab report.
| KDIGO GFR category | eGFR range, mL/min/1.73 m2 | Plain-English meaning |
|---|---|---|
| G1 | >=90 | Normal or high eGFR, if no other kidney damage is present |
| G2 | 60-89 | Mildly decreased eGFR |
| G3a | 45-59 | Mild to moderately decreased eGFR |
| G3b | 30-44 | Moderately to severely decreased eGFR |
| G4 | 15-29 | Severely decreased eGFR |
| G5 | <15 | Kidney failure range |
The chart describes filtering level. It does not explain the cause, predict your individual future, or replace a medical review.
Normal Range
For eGFR, reports often describe values above 90 mL/min/1.73 m2 as normal, with the important note that eGFR can decline with age. Use the range printed on your own lab report. If your report lists a creatinine value too, common adult reference ranges are 0.7-1.3 mg/dL for men and 0.5-0.95 mg/dL for women, but your own lab's range comes first.
Normal eGFR does not automatically rule out every kidney issue if urine markers are abnormal. Likewise, a mildly reduced eGFR in an older adult may be interpreted differently from the same number in a younger adult. The chart is the start of the conversation.
How To Use The Chart Without Overreading It
First, find your eGFR and match it to the KDIGO category. Next, look for the date and compare it with prior results. Then check creatinine, BUN, cystatin C if measured, and urine markers if ordered. This sequence prevents a common mistake: treating a single eGFR category as if it explains everything.
A category can change temporarily when creatinine changes. Dehydration, a high-protein or meat-heavy meal, creatine supplements, intense exercise, high muscle mass, and certain medications can raise creatinine. That can lower the calculated eGFR without proving a long-term kidney decline.
What Stage 3 Means On The Chart
Stage 3 is split into G3a and G3b. G3a is eGFR 45-59 mL/min/1.73 m2. G3b is 30-44 mL/min/1.73 m2. The split matters because G3b reflects a lower filtering range than G3a, but both still need context from the rest of the report.
If you see stage 3 language on a report, check whether the eGFR has been below 60 for at least 3 months or whether this is the first time it has appeared. A first abnormal result often leads to repeat testing or additional urine testing rather than an immediate conclusion from the chart alone.
Related Lab Tests To Check Together
Serum creatinine is the blood value often used to calculate eGFR. BUN, with a common reference range around 7-20 mg/dL, can rise for kidney and non-kidney reasons, including dehydration or high protein intake. Cystatin C, commonly around 0.6-1.2 mg/L depending on method, is less affected by muscle mass and can support a more accurate eGFR estimate when combined with creatinine.
Urine albumin-to-creatinine ratio is another related indicator. It helps clinicians look for signs of kidney damage that may not be obvious from eGFR alone.
When To Talk With A Doctor
Talk with a doctor if your eGFR falls into G3a, G3b, G4, or G5, if any category change persists, or if creatinine rises on repeated tests. You should also ask for guidance if the result appeared after dehydration, infection, intense exercise, or a medication change, because those details may affect the next step.
Urgency depends on the full clinical picture. A stage chart is not designed to tell you what treatment you need. It is a shared language for reviewing kidney function with your clinician.
Frequently Asked Questions
What are the CKD stages by eGFR? KDIGO categories are G1 >=90, G2 60-89, G3a 45-59, G3b 30-44, G4 15-29, and G5 <15 mL/min/1.73 m2.
Does one low eGFR mean I have CKD? No. CKD requires a kidney abnormality that persists for at least 3 months, such as eGFR below 60 or another marker of kidney damage.
What stage is eGFR 50? An eGFR of 50 mL/min/1.73 m2 falls in KDIGO G3a. It still needs repeat results and clinical context.
What stage is eGFR 35? An eGFR of 35 mL/min/1.73 m2 falls in KDIGO G3b. Review it with your doctor alongside creatinine, BUN, and urine markers.
What eGFR is kidney failure range? KDIGO G5 is eGFR below 15 mL/min/1.73 m2.
Can dehydration change my CKD stage on a report? Dehydration can raise creatinine and lower calculated eGFR, so a temporary stage change may need repeat testing.
Should cystatin C be used for staging? KDIGO 2024 recommends using creatinine with cystatin C when available for a more accurate estimate.
Why does the chart mention urine albumin? CKD assessment is not only eGFR. Urine albumin-to-creatinine ratio can show kidney damage markers that complement the eGFR stage.
How MediLens Helps Track This Over Time
MediLens helps turn a stage chart into a timeline. Instead of trying to remember whether an eGFR was 62 last year or 52 last month, you can scan reports and see the values next to their dates. The app keeps related kidney markers together, so creatinine, eGFR, BUN, cystatin C, and urine markers are easier to compare before a visit. That is especially useful when a stage label changes and you need to know whether it is new, repeated, or improving.
Key Takeaways
- KDIGO CKD stages are based on eGFR ranges from G1 through G5.
- CKD requires kidney abnormality for at least 3 months, not just one chart match.
- Stage 3 is split into G3a at 45-59 and G3b at 30-44 mL/min/1.73 m2.
- Creatinine-based eGFR can be affected by hydration, diet, exercise, muscle mass, and some medications.
- Use the chart with your own lab report, urine markers, and your doctor's guidance.
This article is for general education, based on KDIGO clinical practice guidelines and public materials from the National Kidney Foundation (NKF). It is not a diagnosis or treatment advice and does not replace your doctor. Interpret results using the reference ranges on your own lab report and your physician's guidance.
A single lab result only tells part of the story. MediLens helps you scan lab reports, organize your results, compare changes over time, and better understand your long-term health trends.