Renal Function & eGFR
Every renal function & egfr calculator on CalcEngines — unit converters, derived indices and interpretive tools, each with its formula, a worked example and the reference intervals it is judged against.
27 calculators in this section
- BUN to Creatinine Ratio CalculatorCalculate the BUN:creatinine ratio, a quick pointer toward pre-renal, renal or other causes of an abnormal kidney profile.
- CKD GFR Stage Calculator (G1–G5)Place an eGFR into its KDIGO G1–G5 category, and see why a normal-range result is not, by itself, a diagnosis of chronic kidney disease.
- CKD Risk Heat Map Interpreter (KDIGO G and A)Place an eGFR and a urine albumin-creatinine ratio on the KDIGO chronic kidney disease heat map: the G category (G1 to G5), the A category (A1 to A3), the risk colour — low, moderately increased, high or very high — and how often KDIGO's grid suggests checking eGFR and ACR. CKD itself needs the abnormality to persist for more than 3 months.
- CKD-EPI 2021 Creatinine eGFR CalculatorEstimate GFR from creatinine, age and sex using the 2021 race-free CKD-EPI equation, the current standard for adults.
- CKD-EPI 2021 Creatinine-Cystatin C eGFR CalculatorThe most accurate routine estimate of GFR, combining creatinine and cystatin C in the 2021 race-free equation.
- CKD-EPI Cystatin C eGFR CalculatorEstimate GFR from cystatin C alone, independent of muscle mass — useful when creatinine cannot be trusted.
- Cockcroft-Gault Creatinine Clearance CalculatorEstimate creatinine clearance in mL/min — the equation most drug labels specify for renal dose adjustment.
- Creatinine Unit ConverterConvert serum creatinine between mg/dL and µmol/L, with adult reference ranges and what a change actually means.
- Cystatin C Unit ConverterConvert cystatin C between mg/L, µg/mL and nmol/L, with reference ranges and when to prefer it over creatinine.
- eGFR BSA Adjustment CalculatorConvert an indexed eGFR (mL/min/1.73 m²) to an absolute clearance in mL/min for drug dosing.
- Fractional Excretion of Magnesium (FEMg) CalculatorIdentify renal magnesium wasting as the cause of hypomagnesaemia, correcting for the fraction of serum magnesium that is protein-bound and never filtered.
- Fractional Excretion of Phosphate (FEPO4) CalculatorIdentify renal phosphate wasting as the cause of hypophosphataemia, where the expected response is near-complete tubular conservation.
- Fractional Excretion of Potassium (FEK) CalculatorIn hypokalaemia, separate extrarenal potassium loss from inappropriate renal potassium wasting.
- Fractional Excretion of Sodium (FENa) CalculatorDistinguish a pre-renal pattern from intrinsic renal injury by comparing sodium clearance with creatinine clearance — only valid before diuretics have been given.
- Fractional Excretion of Urea (FEUrea) CalculatorDistinguish pre-renal from intrinsic renal injury when diuretics have already been given, using urea instead of sodium clearance.
- Fractional Excretion of Uric Acid (FEUA) CalculatorHelp separate SIADH from volume depletion in hyponatraemia — a raised FEUA persists in SIADH even after the sodium is corrected.
- KDIGO AKI Stage CalculatorStage acute kidney injury from a creatinine pair and urine output using the KDIGO criteria, taking whichever of the two gives the higher stage.
- KDIGO Albuminuria Category (A1–A3) CalculatorClassify a urine albumin-creatinine ratio into the KDIGO A1–A3 categories and see how it sharpens cardiovascular and renal risk at any eGFR.
- Kt/V Calculator (Dialysis Adequacy)Calculate delivered Kt/V with the Daugirdas second-generation single-pool formula, the standard measure of haemodialysis adequacy.
- MDRD eGFR Calculator (4-Variable)The legacy MDRD Study equation, still quoted in older records, drug labels and trial criteria.
- Measured Creatinine Clearance (24-Hour Urine)Calculate creatinine clearance from a timed 24-hour urine collection and a paired serum creatinine.
- Renal Failure Index CalculatorCalculate the renal failure index from urine and plasma values to help distinguish a pre-renal from an intrinsic pattern of acute kidney injury.
- Schwartz Bedside Paediatric eGFR CalculatorEstimate GFR in children from height and creatinine using the bedside Schwartz equation.
- Urea and BUN Unit ConverterConvert between BUN in mg/dL, urea in mg/dL and urea in mmol/L — three ways of reporting the same molecule.
- Urea Reduction Ratio (URR) CalculatorCalculate the urea reduction ratio, the simplest bedside measure of dialysis adequacy, from pre- and post-dialysis BUN.
- Urine Output Calculator (mL/kg/hr)Calculate urine output in mL/kg/hr and apply the KDIGO thresholds used to define acute kidney injury.
- Urine to Plasma Osmolality Ratio CalculatorDivide urine osmolality by serum osmolality to gauge whether the kidney is concentrating urine appropriately, and how early that ability tends to fail.