Free Tools

Free health tools, no account needed

Calculators that turn your lab results into plain-language insights — plus a free AI health assessment that maps your symptoms to personalized patterns.

Free Health Assessment

3 minutes, 13 health topics, personalized AI report by email.

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Metabolic health calculators

Instant, research-backed scores from the lab values you already have. Free forever, no account needed — with reference ranges and plain-language interpretation.

HOMA-IR Calculator

Estimate insulin resistance from fasting glucose and insulin — includes the QUICKI sensitivity index.

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TyG Index Calculator

Combine fasting triglycerides and glucose into a single insulin-resistance marker — no insulin assay needed.

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TG/HDL Ratio Calculator

Pull a cardiometabolic risk signal straight from your standard lipid panel.

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Cholesterol Ratio Calculator

Two cholesterol ratios from your standard lipid panel — TC/HDL and LDL/HDL, with reference bands and conversion-free mmol/L math.

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VLDL Calculator

Estimate VLDL and LDL cholesterol from a standard lipid panel — the Friedewald equations, with the TG≥400 limits spelled out.

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Waist-to-Height Ratio Calculator

Check central adiposity with just a tape measure — keep your waist to less than half your height.

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Body Roundness Index (BRI) Calculator

Body Roundness Index from waist + height — the tape-measure metric that models body shape, not just weight.

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A Body Shape Index (ABSI) Calculator

A Body Shape Index from waist, height, and weight — with a z-score against people your age and sex (NHANES reference).

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Waist-to-Hip Ratio Calculator

Waist ÷ hip with two tape measurements — WHO cut-offs for men and women, and how-to-measure guidance.

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Metabolic Syndrome Risk Score

Count how many of the five published metabolic syndrome criteria your numbers currently meet.

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ApoB/ApoA1 Ratio Calculator

Measure the balance between atherogenic and protective lipoprotein particles from an advanced lipid panel.

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A1c ↔ Average Glucose Converter

Convert A1c to estimated average glucose (eAG) or average glucose back to A1c — bidirectional, with reference chart.

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Cholesterol Units Converter (mg/dL ↔ mmol/L)

Convert cholesterol and triglycerides between mg/dL and mmol/L — bidirectional, with the exact factors for each.

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Non-HDL Cholesterol Calculator

Total cholesterol minus HDL — all atherogenic particles in one number, no fasting or triglyceride limits.

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AIP Calculator (Atherogenic Index of Plasma)

The Atherogenic Index of Plasma — log of TG/HDL linked to LDL particle size, with correct mmol/L handling.

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Blood Sugar Converter (mg/dL ↔ mmol/L)

Convert blood glucose between mg/dL and mmol/L — bidirectional with the ÷18 factor and a reference chart.

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Thyroid health calculators

Ratio-based views of your thyroid labs — conversion, axis balance, and the numbers behind the numbers. Free, no account needed.

Thyroid Ratio Calculator

Three ratio views of your thyroid labs in one page: FT3/rT3, FT3/FT4, and Jostel's TSH Index.

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Nutrient status tools

Environment- and symptom-based estimators for nutrient status — no lab order required. Free, no account needed.

UVB Vitamin D Synthesis Calculator

Estimate how much midday sun your skin type needs for vitamin D synthesis at today's UV index.

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Copper/Zinc Ratio Calculator

Copper ÷ zinc from two serum values — the balance functional medicine practitioners read as one number.

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Transferrin Saturation Calculator (TSAT)

TSAT from serum iron + TIBC — iron status percentage with reference bands and ferritin pairing guidance.

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Omega-3 Index Calculator (with Omega-6:3 Ratio)

Calculate your omega-3 index from EPA + DHA on a fatty acid panel, plus your omega-6:3 ratio — with research-convention bands.

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Immune & inflammation calculators

Research-backed composite markers from routine lab values — inflammation and immune context in plain language. Free, no account needed.

hs-CRP:Albumin Ratio Calculator

Combine inflammation and nutritional status into one research-grade composite marker.

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NLR Calculator (Neutrophil-to-Lymphocyte Ratio)

Neutrophil-to-lymphocyte ratio from a standard CBC differential — an immune-balance signal with research-cohort reference bands.

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Albumin/Globulin (A/G) Ratio Calculator

A/G ratio from albumin + total protein (or look up the printed value) — with an interpretation table for high and low readings.

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Gut health tools

Simple, shareable tools for digestive health — interpret what your body is telling you. Free, no account needed.

Bristol Stool Chart Interpreter

The seven-type chart clinicians actually use — pick what you see, get a plain-language read.

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Men's health calculators

Hormone math from the lab values you already have — free and bound fractions, ratios, and what they mean. Free, no account needed.

Free Testosterone Calculator

Calculated free testosterone from total T, SHBG, and albumin — the Vermeulen equation, with percent free T.

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Hormone health calculators

Ratio-based views of your hormone labs — estrogen/progesterone balance, FSH/LH, T/E2, and the numbers behind the numbers. Free, no account needed.

Estrogen to Progesterone Ratio Calculator

Check the balance between estrogen and progesterone from your lab report — Pg/E2 and the inverse ratio, with reference bands.

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FSH LH Ratio Calculator

Compute your LH:FSH or FSH:LH ratio from day-3 labs — with an interpretation table and plain-language context.

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Testosterone to Estradiol Ratio Calculator (T/E2)

Your T/E2 ratio from testosterone (ng/dL) and estradiol (pg/mL) — with the unit math made explicit and honest community-convention context.

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Liver health calculators

Pattern-based views of your liver enzymes — the numbers behind the numbers on a standard metabolic panel. Free, no account needed.

AST/ALT Ratio Calculator (De Ritis)

The De Ritis ratio from your liver panel — AST ÷ ALT with a pattern interpretation table and plain-language context.

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FIB-4 Score Calculator (Fibrosis-4 Index)

FIB-4 fibrosis screening score from age, AST, ALT, and platelets — with standard risk bands and age-adjusted cutoffs.

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APRI Calculator (AST-to-Platelet Ratio Index)

APRI score from AST and platelet count — the original biopsy-free liver fibrosis screening index, with standard cutoffs explained.

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General chemistry calculators

The classic ratios and corrections hiding in a standard metabolic panel (CMP) — kidney context, calcium status, acid-base balance. Free, no account needed.

BUN/Creatinine Ratio Calculator

BUN ÷ creatinine from your metabolic panel — the classic ratio for reading kidney values in context, with textbook reference bands.

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Corrected Calcium Calculator

Albumin-corrected calcium via the Payne formula — what your total calcium really means when albumin is off, with reference bands.

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Anion Gap Calculator

Anion gap from sodium, chloride, and bicarbonate — the first-step acid-base signal on any metabolic panel, with textbook ranges.

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Want a calculator we don't have yet?

Tell us which health metric you'd like a tool for — we build based on requests.

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