What is a normal blood test range?

A normal or reference range is the band of results seen in most healthy people for a given test, measured on a particular laboratory's equipment. It is a statistical guide rather than a strict boundary between health and disease. Results slightly outside the range are common and often harmless, and a result within the range can still be significant in context. Because methods and populations differ, always compare your result against the reference range printed on your own report, and discuss anything you are unsure about with your doctor.

Why are the ranges on my report different from this chart?

Reference ranges vary between laboratories because they depend on the analyser, the testing method, and the local population used to define 'normal'. They also change with age, sex, and pregnancy. That is why the range printed next to your result on your own report is the one that applies to you, and this chart is only an approximate general guide. If your result is flagged as high or low, it is best understood alongside your symptoms, history, and other tests, which is what your doctor does.

What should I do if my result is outside the normal range?

First, do not panic: a single result just outside a range is very common and is not a diagnosis. Note the exact value and range, and any symptoms you have, and bring them to your doctor, who interprets the result in the context of your health, medications, and other tests. Some out-of-range results simply need a repeat test; others prompt further assessment. Our detailed guide for each test explains what high and low results can mean and what questions to ask.

Blood Test Normal Ranges: Plain-English Reference Chart

Quick answer: This chart lists typical adult normal ranges for common blood and health tests, each linked to a full plain-English guide. Ranges are approximate and vary by lab, age, and sex, always compare against the reference range on your own report and discuss results with your doctor.

This is a plain-English reference chart of typical adult normal ranges for the blood and health tests people most often see on a report, each linked to a detailed preparation guide. It is designed to help you understand your results and prepare questions before a doctor’s appointment. Last updated 3 July 2026.

Read this first: The ranges below are approximate typical adult values and differ by laboratory, age, sex, pregnancy, and testing method. Your own report prints the exact reference range your lab used, always compare against that, not this chart. This page is for understanding and appointment preparation, not diagnosis. A result outside a range is common and is not a diagnosis on its own; discuss any result with your doctor.

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Kidney & electrolytes

Test	Typical adult range*	Helps assess	Full guide
eGFR	≥90 normal; 60, 89 mildly reduced; <60 for ≥3 months suggests CKD	Kidney filtering	eGFR guide
Creatinine	~60–110 µmol/L (sex-dependent)	Kidney function	Creatinine
Urea / BUN	~2.5–7.8 mmol/L (BUN ~7–20 mg/dL)	Kidney / hydration	Urea (BUN)
Urine ACR	<3 mg/mmol	Early kidney / protein leak	ACR
Sodium	135–145 mmol/L	Fluid & salt balance	Electrolytes
Potassium	3.5–5.0 mmol/L	Heart rhythm / kidney	Potassium
Bicarbonate (CO₂)	22–29 mmol/L	Acid-base balance	Bicarbonate
Magnesium	0.7–1.0 mmol/L	Muscle, nerve & heart	Magnesium

Liver

Test	Typical adult range*	Helps assess	Full guide
ALT	~7–56 U/L (often <40)	Liver cell health	ALT & AST
AST	~10–40 U/L	Liver / muscle	ALT & AST
GGT	men ~10–71, women ~6–42 U/L	Bile ducts / alcohol	GGT
Albumin	35–50 g/L	Liver / nutrition	Albumin

Heart

Test	Typical adult range*	Helps assess	Full guide
Troponin	below the lab’s assay cut-off (high-sensitivity, sex-specific)	Heart-muscle injury	Troponin
BNP / NT-proBNP	low = heart failure unlikely (cut-offs vary by assay & age)	Heart strain	BNP / NT-proBNP
D-dimer	<0.5 mg/L FEU (often age-adjusted)	Clot breakdown	D-dimer

Blood count & iron

Test	Typical adult range*	Helps assess	Full guide
Haemoglobin	men 130–170, women 120–155 g/L	Anaemia / oxygen	Haemoglobin
White cell count	4, 11 ×10⁹/L	Infection / immunity	Full Blood Count
Platelets	150, 400 ×10⁹/L	Clotting	Full Blood Count
Ferritin	men ~30–300, women ~15–200 µg/L	Iron stores	Ferritin
Vitamin B12	~200–900 ng/L	Nerves / blood	Vitamin B12
Folate	>3–4 µg/L (serum)	Blood formation	Folate

Inflammation

Test	Typical adult range*	Helps assess	Full guide
CRP	<5 mg/L	Inflammation / infection	CRP
ESR	roughly age÷2 (men); (age+10)÷2 (women) mm/hr	Inflammation	ESR

Diabetes, cholesterol & metabolic

Test	Typical adult range*	Helps assess	Full guide
HbA1c	<42 mmol/mol (<6.0%); 42, 47 prediabetes; ≥48 (≥6.5%) diabetes	3-month blood sugar	HbA1c
Fasting glucose	3.9–5.5 mmol/L; 6.1, 6.9 impaired; ≥7.0 diabetes	Blood sugar	Fasting glucose
Total cholesterol	<5.0 mmol/L (target varies by risk)	Heart risk	Cholesterol
Total:HDL ratio	<4 (lower is better)	Heart risk	Cholesterol ratio
Uric acid	men ~0.20–0.43, women ~0.14–0.36 mmol/L	Gout / kidney	Uric acid

Thyroid & hormones

Test	Typical adult range*	Helps assess	Full guide
TSH	~0.4–4.0 mIU/L	Thyroid function	TSH
Free T4	~9–25 pmol/L	Thyroid hormone	Thyroid tests
Cortisol (morning)	~140, 700 nmol/L (varies through the day)	Adrenal / stress	Cortisol

Bone, minerals & pancreas

Test	Typical adult range*	Helps assess	Full guide
Calcium (corrected)	2.2–2.6 mmol/L	Bone, nerve & muscle	Calcium
Phosphate	0.8–1.5 mmol/L	Bone / kidney	Phosphate
Vitamin D	>50 nmol/L sufficient; 30, 50 insufficient; <30 deficient	Bone / immune	Vitamin D
Amylase / Lipase	laboratory-specific (lipase is more specific)	Pancreas	Lipase & Amylase

*Approximate adult ranges in SI units (common where used elsewhere). Not for diagnosis, see the caution above.

How to read a reference range

A “reference range” (or normal range) is the band of values seen in most healthy people for that test, on that lab’s equipment. It is a guide, not a hard line between healthy and unhealthy: results just outside a range are common and often harmless, while a result inside the range can still matter in context. Ranges also shift with age, sex, pregnancy, and the analyser used, which is why the range on your report is the one that applies to you.

Tests measured differently (not a single blood range)

Some results are not a single blood number: blood pressure (below ~120/80 is optimal; ~140/90 or above in clinic is raised), bone density / DEXA (T-score ≥-1 normal, -1 to -2.5 osteopenia, ≤-2.5 osteoporosis), and spirometry lung function (an FEV1/FVC ratio below ~0.7 suggests airway narrowing). Broad overviews: reading blood test results, kidney function tests, liver function tests, thyroid tests, iron studies, urinalysis.

HOW TO CITE THIS PAGE

DoctorVisitPrep. “Blood Test Normal Ranges: A Plain-English Reference Chart.” doctorvisitprep.com. Last updated 3 July 2026. https://doctorvisitprep.com/blood-test-normal-ranges-reference-chart/

Journalists & researchers: this chart may be quoted with attribution and a link. See our editorial standards.

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Medical Disclaimer: This guide is for informational and preparation purposes only. It does not constitute medical advice, diagnosis, or treatment. Always consult a qualified medical professional for guidance specific to your situation.