Free Online Calculators
434+ calculators for finance, health, math, engineering, and more. No signup required.
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Popular Calculators
Most-used tools across all categories
MAP Calculator - Mean Arterial Pressure
Calculate Mean Arterial Pressure (MAP) from systolic and diastolic blood pressure readings. Professional medical tool for cardiovascular assessment, organ perfusion evaluation, and clinical decision-making.
Health →BSA Calculator
Calculate Body Surface Area (BSA) using validated medical formulas including Du Bois, Mosteller, and Haycock. Essential for chemotherapy dosing, cardiac assessments, and clinical calculations with detailed medical reference content.
Health →Weight Gain Calculator
Calculate your personalized weight gain plan with calorie targets, macro breakdown, and healthy timeline recommendations for sustainable muscle building.
Health →BMI Calculator for Men
Professional BMI calculator designed specifically for men's unique physiological characteristics. Accounts for male muscle mass distribution, fat storage patterns, and age-related body composition changes with personalized fitness recommendations.
Health →Trigonometry Calculator
Calculate trigonometric functions including sine, cosine, tangent, and their inverses. Perfect for students, engineers, and professionals with detailed explanations and formulas.
Math →BMI Calculator for Women
Professional BMI calculator designed specifically for women's health needs with female-specific health considerations, reproductive health guidance, and personalized recommendations based on female physiology.
Health →Wheel Size Calculator
Calculate the impact of changing wheel sizes on tire specifications, speedometer accuracy, and vehicle performance. Professional tool for wheel upgrades and plus sizing projects with comprehensive analysis.
Automobile →Calorie Deficit Calculator for Women
Calculate optimal calorie deficits specifically designed for female physiology. Account for hormonal fluctuations, menstrual cycles, and women's unique metabolic characteristics for safe, sustainable weight loss.
Health →Recently Added
Fresh calculators just added to our collection
Crochet Stitch Count Calculator
Calculate the exact number of stitches and rows needed for any crochet project based on your gauge and desired dimensions.
Crochet Row Count Calculator
Calculate the exact number of rows needed for any crochet project based on your row gauge and desired length.
Crochet Blanket Size Calculator
Calculate the exact stitches, rows, and foundation chain for any crochet blanket size from baby to king with adjustable overhang.
Crochet Amigurumi Sizing Calculator
Calculate stitch counts, body dimensions, and yarn requirements for any amigurumi crochet project.
Crochet Granny Square Calculator
Calculate how many granny squares you need and total yarn for blankets, bags, garments, and more.
Crochet C2C (Corner-to-Corner) Calculator
Calculate total blocks, diagonal rows, and yarn requirements for corner-to-corner crochet projects.
Why Complete Calculators?
Accurate Formulas
Each calculator uses verified formulas from authoritative sources. Check our sources section on each tool.
Private & Secure
Calculations happen in your browser. We don't store your data or require any login.
Works Everywhere
Mobile-friendly design. Use on your phone, tablet, or desktop - no app download needed.
Frequently Asked Questions
Are these calculators really free?
Yes, all 434+ calculators are completely free to use. No subscription, no hidden fees, no signup required. We support the site through minimal, non-intrusive advertising.
How accurate are the calculations?
We use industry-standard formulas and cite our sources on each calculator page. For professional or legal decisions, we recommend consulting with a qualified professional.
Is my data private?
All calculations are performed locally in your browser. Your input data is never sent to our servers or stored anywhere. Close the page and your data is gone.
Can I suggest a new calculator?
We're always adding new calculators based on user needs. Contact us with your suggestion and we'll consider adding it to our collection.
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