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In-depth health guides paired with interactive tools. Every topic comes with expert-level articles, visual results, and citations from WHO, NIH, and peer-reviewed research.

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Every category covers both the tools and the knowledge to understand your results.

Featured Guide

Pregnancy Weight Gain: Your Complete Guide

Understand healthy pregnancy weight gain week by week with IOM guidelines. Read our evidence-based guide, then use the interactive tracker to see where you stand with visual charts and personalized ranges.

📖 Evidence-based guide📈 Interactive tracker👶 Twin support
Read the Guide →
Preview
Weight gain
7.0 kg
Target range
5.0–7.0 kg
BMI Category
Normal
Week
24
Week 24 progressOn track ✓

All Calculators & Tools

40 tools available — each with an in-depth guide

POPULAR
Pregnancy

Pregnancy Weight Gain Calculator

Week-by-week tracking based on IOM guidelines with visual trajectory chart.

Calculator + Guide →
ToolTool
POPULAR
Fitness

TDEE Calculator

Total Daily Energy Expenditure using Mifflin-St Jeor equation.

Calculator + Guide →
ToolTool
Body Metrics

BMI Calculator

Visual gauge with age and gender-adjusted interpretation.

Calculator + Guide →
ToolTool
Mental Health

Stress Level Test

PSS-10 based clinically validated stress assessment.

Calculator + Guide →
ToolTool
Pregnancy

Due Date Calculator

Estimated delivery date from LMP, conception, or IVF transfer.

Calculator + Guide →
ToolTool
Fitness

Macro Calculator

Personalized macro splits for keto, PCOS, balanced, and more.

Calculator + Guide →
ToolTool
Pregnancy

HCG Doubling Time

Track early pregnancy HCG levels and doubling rate.

Calculator + Guide →
ToolTool
Conditions

A1C to Blood Sugar Converter

Convert A1C percentage to estimated average blood sugar.

Calculator + Guide →
ToolTool
Fitness

Body Fat Calculator

Navy method and skinfold-based body fat estimation.

Calculator + Guide →
ToolTool
Fitness

Calorie Deficit Calculator

Calculate your ideal deficit for sustainable weight loss.

Calculator + Guide →
ToolTool
Pregnancy

Ovulation Calculator

Predict your most fertile days based on cycle length.

Calculator + Guide →
ToolTool
Mental Health

Sleep Quality Calculator

PSQI-based sleep quality assessment with improvement tips.

Calculator + Guide →
ToolTool
Pregnancy

Fetal Weight Percentile

Track baby's growth against WHO standards week by week.

Calculator + Guide →
ToolTool
Fitness

Protein Intake Calculator

Daily protein needs based on weight, activity, and goals.

Calculator + Guide →
ToolTool
Body Metrics

BMI Calculator for Teens

Age and sex-specific BMI percentiles for ages 2-19.

Calculator + Guide →
ToolTool
Conditions

GFR Calculator

Estimate kidney function using the CKD-EPI 2021 equation.

Calculator + Guide →
ToolTool
Pregnancy

Pregnancy Safe Food Checker

Search if a food is safe to eat during pregnancy.

Calculator + Guide →
ToolTool
Body Metrics

BMR Calculator

Basal Metabolic Rate using Mifflin-St Jeor and Harris-Benedict.

Calculator + Guide →
ToolTool
Fitness

One Rep Max Calculator

Estimate your 1RM with percentage-based training chart.

Calculator + Guide →
ToolTool
Body Metrics

Ideal Weight Calculator

Four formulas compared — Devine, Robinson, Miller, Hamwi.

Calculator + Guide →
ToolTool
Mental Health

Burnout Quiz

Assess burnout risk across exhaustion, cynicism, and efficacy.

Calculator + Guide →
ToolTool
Mental Health

Anxiety Self-Assessment

GAD-7 clinically validated anxiety screening.

Calculator + Guide →
ToolTool
Fitness

Lean Body Mass Calculator

Estimate lean mass using Boer and James formulas.

Calculator + Guide →
ToolTool
Body Metrics

Calorie Calculator for Women Over 50

Daily calorie needs with menopause and sarcopenia considerations.

Calculator + Guide →
ToolTool
Pregnancy

Contraction Timer

Track contraction frequency, duration, and the 5-1-1 pattern.

Calculator + Guide →
ToolTool
Mental Health

ADHD Self-Assessment

ASRS v1.1 Part A screener for adult ADHD.

Calculator + Guide →
ToolTool
Conditions

Anemia Risk Checker

Symptom-based anemia risk screening.

Calculator + Guide →
ToolTool
Body Metrics

Body Frame Size Calculator

Determine small, medium, or large frame from wrist measurement.

Calculator + Guide →
ToolTool
Body Metrics

TDEE Calculator for Teens

Growth-adjusted calorie needs for ages 10-19.

Calculator + Guide →
ToolTool
Body Metrics

Protein Needs for Seniors

Daily protein targets for 65+ to prevent sarcopenia.

Calculator + Guide →
ToolTool
Conditions

Kidney Function Calculator

Detailed CKD staging with action recommendations.

Calculator + Guide →
ToolTool
Fitness

Macro Calculator for PCOS

PCOS-specific macro splits by phenotype.

Calculator + Guide →
ToolTool
Pregnancy

IVF Due Date Calculator

Due date from IVF transfer — 3-day or 5-day, fresh or FET.

Calculator + Guide →
ToolTool
Pregnancy

Baby Growth Percentile

WHO growth standards from birth to 5 years.

Calculator + Guide →
ToolTool
Mental Health

Sleep Calculator

Ideal bedtime by sleep cycles and age group.

Calculator + Guide →
ToolTool
Conditions

Cholesterol Ratio Calculator

TC/HDL, LDL/HDL, and triglyceride/HDL ratios.

Calculator + Guide →
ToolTool
Body Metrics

Waist-to-Hip Ratio

WHO cardiovascular risk from waist and hip measurements.

Calculator + Guide →
ToolTool
Conditions

Vitamin D Calculator

Daily IU needs by body weight and current level.

Calculator + Guide →
ToolTool
Conditions

Thyroid Function Calculator

TSH interpretation with pregnancy-adjusted ranges.

Calculator + Guide →
ToolTool
Mental Health

Postpartum Depression Screening

Edinburgh Postnatal Depression Scale (EPDS).

Calculator + Guide →
ToolTool

Not just a number. A complete picture.

Most calculator sites give you a result and leave. We give you understanding.

✏️01

Enter your data

Simple inputs with metric/imperial support. No signup, no accounts.

📊02

See visual results

Color-coded gauges, trajectory charts, comparison graphics.

📖03

Read the full context

A 2,000-word evidence-based article explains what your results mean.

🔗04

Continue your journey

Related tools link together. TDEE → macros → protein — one flow.

Built on published science, not guesswork

Every calculator uses established, peer-reviewed formulas — Mifflin-St Jeor for TDEE, IOM guidelines for pregnancy, WHO growth standards for child development. We cite the exact equation and the original paper on every page.

Our articles pull information exclusively from authoritative sources: WHO, NIH, ACOG, Mayo Clinic, and PubMed studies. Every key claim is cross-referenced against at least two major medical references.

WHO
World Health Organization
Growth standards, BMI
NIH
National Institutes of Health
Nutritional guidelines
IOM
Natl Academy of Medicine
Pregnancy weight gain
ACOG
American College OB-GYN
Reproductive health

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