Type your numbers in. Get an honest read — clinical reference range vs. functional/optimal target — for the markers people actually look at: thyroid, metabolic, lipids, liver, sex hormones, inflammation, iron, vitamin D.
Reference ranges below assume adult, non-pregnant, US labs. Units chosen to match LabCorp/Quest defaults.
Clinical reference ranges are the middle 95% of whoever happened to walk into the lab. That includes plenty of people who are insulin resistant, vitamin-D deficient, and inflamed. The "optimal" column is what longevity-leaning clinicians actually aim for — not what the lab report flags.
HbA1c, ferritin, and free testosterone can all swing 10–15% week to week. Two readings 3–6 months apart, drawn fasted and at consistent times, beat one reading at any precision. Trend > single point.
A free T3 at the low end with normal energy, sleep, and body temperature is not the same finding as the same number in someone exhausted and cold. Symptoms anchor the read. Numbers without symptoms are a starting point, not a diagnosis.
This tool compares numbers to reference ranges. It does not diagnose anything. Abnormal labs deserve a real conversation with a clinician, not a webpage. If anything flags red, that is a reason to book an appointment — not a reason to panic, and not a reason to self-treat.
The lab 'normal range' (a.k.a. reference range) is the middle 95% of values from the lab's reference population — meaning 2.5% of healthy people fall below and 2.5% above. It's a statistical bracket, not a health target. 'Optimal range' is narrower and based on outcomes data (e.g., where cardiovascular risk is lowest, where energy/mood is best). Many results inside 'normal' are sub-optimal for symptoms or long-term risk.
Standard TSH range (0.4–4.5 mIU/L) is wide. Symptomatic hypothyroidism often presents with TSH 2.5–4.5 — technically 'normal' but elevated relative to optimal (~1.0–2.5 in most outcome studies). Also: TSH alone misses central hypothyroidism (pituitary issue) and tissue-level thyroid resistance. A full panel should include TSH, free T4, free T3, and antibodies (TPO, TgAb).
LDL-C measures cholesterol content carried in LDL particles. ApoB measures the number of atherogenic particles (each LDL, VLDL, IDL, and Lp(a) particle carries one ApoB). When LDL particles are small and dense (common in insulin resistance), LDL-C looks normal but ApoB is high — and ApoB is the better predictor of cardiovascular risk. If only one is measured, prefer ApoB.
Glycated hemoglobin — the percentage of your red blood cell hemoglobin that has glucose stuck to it. RBCs live ~120 days, so HbA1c reflects average blood glucose over the past 2–3 months. <5.7% is considered normal, 5.7–6.4% is pre-diabetes, ≥6.5% is diabetes. Caveat: anemia, hemoglobin variants, and high RBC turnover can falsely lower HbA1c. If suspicious, also check fasting glucose and fasting insulin.
Most common causes: NAFLD/MAFLD (fatty liver, often linked to insulin resistance), alcohol, statins or NSAIDs, hard recent workouts (especially eccentric or resistance), viral hepatitis. An ALT:AST ratio >2 often suggests alcohol; <1 suggests muscle damage or viral. Trend matters more than a single elevated reading — repeat in 4–6 weeks after lifestyle adjustments before adding more workup.
Lab ranges typically span 240–950 ng/dL. Symptomatic hypogonadism is generally diagnosed below 300 ng/dL on two separate morning draws, combined with symptoms (fatigue, low libido, mood, erectile dysfunction). Many men in the 300–500 range have symptoms; many in 500–700 feel fine. Total T should always be paired with free T, SHBG, LH, FSH, prolactin, and estradiol before treatment decisions. If you're evaluating whether enclomiphene or HCG is appropriate rather than exogenous TRT, see our fertility-preserving testosterone guide.