Unified Calculator Studio
Solve math operations, calculate loan amortization interest, scale fitness weight indices, and estimate active calorie burns in real-time.
📐 Math
Percent Change Calculator
Find the Percent Increase or Percent Decrease between two values
Percent to Decimal Calculator
Convert Percent to Decimal and Decimal to Percent
Percent to Fraction Calculator
Convert Percent to Fraction and Fraction to Percent
Decimal to Fraction Calculator
Convert terminating and repeating decimals (0.333... = 1/3, 0.1666... = 1/6) into exact fractions. Step-by-step 10x algebraic subtraction proofs. Free.
Number to Words Converter
Convert numbers to words and words to numbers instantly. Supports Millions, Lakhs/Crores, and Myriad systems with legal cheque visualizer.
Factorial Calculator
Solve n factorial problems quickly and accurately with our factorial calculator. Ideal for mathematics enthusiasts and students.
Square Root Calculator
Find the square root of a number
Percentage Calculator
Solve any percentage problem instantly with our visual calculator. Support for increase/decrease, reverse calculations, and fractions.
Discount Calculator
Find the price after discount for different percentage off
Tip Calculator
Calculate tips and split bills instantly. Includes international tipping etiquette.
Volume Calculator
Find the volume of cylinder, sphere, cube, cone, cuboid, pyramid, prism, ellipsoidal, tetrahedron, spherical cap, tank, tube, hollow cylinder, pipe, rectangle, circle , square
Surface Area Calculator
Find the surface area of cylinder, sphere, cube, cone, cuboid, pyramid, prism, ellipsoidal, tetrahedron, spherical cap, tank, tube, hollow cylinder, pipe, rectangle, circle , square
Logarithm Calculator
Find the natural log (log base e) or common log (log base 10) or log of any base
Exponent Calculator
Exponent Calculator - Find the power of given numbers
GCF Calculator (GCD)
Find the greatest / highest common factor of given numbers
LCM Calculator
Find the least common multiple of given numbers
Prime Factors Calculator
Find the Prime factor, factor pairs and factors of a given number.
Prime Number Checker
Find if a given number is prime number or composite number
GPA Calculator
Calculate your weighted or unweighted GPA or cumulative GPA using grades. Convert percentage to gpa or from other point systems to 4.0 scale
Number Scale Converter
Compare and convert large numbers across Short Scale (US/UK), Long Scale (Continental Europe), and the Indian Vedic System (Lakhs, Crores, Arabb). Free.
Scientific Calculator
Powerful scientific calculator with trigonometric functions, logarithms, history, and NLP power search. Perfect for students and professionals.
Triangle Calculator
Calculate the angles of a triangle or sides of a triangle using SSS, SAS or ASA methods.
Long Division Calculator
Divide by Fractions, Divide by Decimals, Divide by Whole numbers and find Quotient, Remainder and Modulus
Area Calculator
Find the area of circle, square, rectangle, triangle, rhombus, parallelogram, trapezoid, pentagon, hexagon and octagon
Correlation Calculator (Pearson r)
Find the correlation between two variables using the Pearson Coefficient formula. Determine if there is positive correlation or negative correlation or No correlation between the datasets
Statistics Calculator
Compute Mean, Median, Mode and Quartiles (Q1, Q2 or Median, Q3) along with Mean, Mode, Variance, Standard Deviation, Standard Error and 3 sigma with histogram
Scientific Notation Calculator
Convert Number to Scientific Format, Scientific Format to Exponent Format, Scientific to Metric Format
Roman Numerals Converter
Numbers to Roman Numeral and Roman Numeral to Number.
Order of Operations Calculator
Solve complex arithmetic expressions with step-by-step solutions using BODMAS or PEMDAS rules. Interactive math studio for students and educators.
💵 Finance
Simple Interest Calculator
Find the simple interest and final amount using principal, interest rate and time
Loan EMI Calculator
Calculate monthly loan EMI, total interest, and visualize your repayment schedule with amortization charts. Fast, accurate, and multi-currency support.
Mortgage Calculator
Calculate monthly mortgage payments (PITI), visualize payoff dates, and explore extra payment savings. Professional amortization schedule included.
Compound Interest Calculator
Free Compound Interest Calculator to plan investments with monthly deposits. Compare scenarios side-by-side and visualize your long-term wealth growth charts.
❤️ Health & Fitness
BMI Calculator
Calculate your bmi using your weight and height
BMR Calculator
Determine Your Basic Calorie Needs at Steady State
Calories to Pounds (lbs) Weight Loss & Body Fat Calculator
Convert calories burned or consumed into pounds (lbs) of body weight. Calculate daily calorie deficits, macro splits, and realistic fat loss timelines using the 3,500 kcal rule.
Calories to Kilograms (kg) Fat Loss & Energy Converter
Convert calories (kcal) and kilojoules (kJ) to kilograms (kg) of body mass. Plan metric fitness targets, explore NIH dynamic metabolic adaptation, and view 100g nutritional benchmarks.
Calories Burned Calculator
Find out how many calories you burn for different exercise and activities
Calorie Intake Calculator
Find out how many calories you consume daily
TDEE Calculator
Determine Your Total Daily Energy Expenditure
Body Adiposity Index
Find your body adipose index percentage (BAI)
Waist-to-Hip Ratio
Determine your body fat distribution using waist-to-hip ratio
Relative Fat Mass (RFM)
Measure your RFM percentage and Estimate Body Fat using Height and Waist Dimensions
Body Surface Area
Find out your body surface area using height and weight
Lean Body Mass
Calculate your lean body mass and body fat % using height and weight
Miles to Calories Calculator
Effortlessly convert miles to calories with our precise Miles to kcal Calculator. Ideal for Fitness and Weight Management Tracking!
Steps to Calories Calculator
Track your fitness progress with our Steps to Calories Calculator on My Browser App Store. Convert Calories to steps and stay on top of your health goals
Breathing Exercise
Visualize and guide your breathing cycles with calming audio and themes
Body Adiposity Index (BAI) Calculator Studio
Calculate Body Adiposity Index (BAI) online. Estimate your body fat percentage from hip circumference and height without using weight scales.
Lean Body Mass (LBM) Calculator Studio
Calculate your Lean Body Mass (LBM) and Fat-Free Mass online. Compares Boer, James, and Hume formulas to determine skeletal muscle and organ weight.
Body Surface Area (BSA) Calculator Studio
Calculate Body Surface Area (BSA) in m² using Mosteller, Du Bois, Haycock, and Gehan-George formulas. Essential for clinical dosages and cardiac index.
🛠️ Utilities
Dog Age Calculator
Convert dog years to human years accurately using modern AVMA veterinary guidelines and breed size (Small, Medium, Large, Giant). 100% Free.
Cat Age Calculator
Convert your cat's age into human years using the AAHA / AAFP Feline Life Stage guidelines. Learn your cat's biological life stage and care milestones. Free.
Age Calculator
Calculate age for a given date of birth.
Image Color Picker
This free and powerful tool extracts all colors from any image and instantly generates a color palette.
Date of Birth (DOB) Calculator
Calculate date of birth from age
Horoscope Zodiac Calculator
Generate Rasi and Navamsa charts, explore 120-year Vimshottari Dasha timelines, and get detailed planetary insights for free
Word Counter
Count words, characters, letters, lines, sentences and paragraphs online
Overview & Capabilities
Welcome to the NexTools Online Calculators & Converters Hub! Explore our comprehensive suite of free, high-precision web calculators engineered for finance, health and fitness, arithmetic, algebra, statistics, geometry, and unit conversions. Built entirely with client-side JavaScript execution, our calculators deliver instant results with step-by-step mathematical breakdowns, interactive graphs, and 100% offline data privacy.
How to Use
Key Features
Related Tools
Percentage Calculator Online
Calculate percentages online with our 3-in-1 tool: What is X% of Y, X is what % of Y, and Percentage Increase/Decrease. Step-by-step arithmetic proofs.
BMI Calculator Online
Calculate your Body Mass Index (BMI) online. Compare your score against WHO classifications, pediatric percentiles, and Asian population thresholds. Free.
Loan EMI Calculator Online
Calculate Equated Monthly Installments (EMI) for home loans, car loans, and personal loans. View monthly amortization schedules, prepayments, and total interest.
Prime Number Checker & Generator
Check if a number is prime online. Find next and previous prime numbers, prime factors, and discover primes using the Sieve of Eratosthenes algorithm.
Compound Interest Calculator
Calculate compound interest with regular monthly deposits. Compare daily, monthly, and annual compounding frequencies to project investment growth.
Frequently Asked Questions
Q Are these online calculators free to use with no subscription fees?
Yes, 100%. Every calculator on NexTools is completely free with no paywalls, subscriptions, or hidden charges.
Q Is my personal financial or health data stored on your servers?
No. All mathematical calculations run entirely client-side within your device's browser engine. No loan figures, body weights, or personal numbers are ever transmitted to or stored on external servers.
Q Can I use these calculators offline without an active internet connection?
Yes! Once loaded in your browser, the calculation engines cache locally, enabling you to continue calculating offline without internet access.
Q Which calculation categories are available in this hub?
Our hub includes 8 specialized categories: Health & Body (BMI, BMR, TDEE, Calorie deficit), Finance (Loan EMI, Mortgage, Compound Interest), Percentages, Number Theory (Primes, GCF, LCM), Algebra (Square Root, Logarithms), Statistics (Correlation, Sample Variance), Geometry (Area, Volume), and Date/Age calculation.
Q Are the formulas based on verified scientific and financial standards?
Yes. Our health tools use WHO and CDC clinical algorithms, our financial tools employ standard reducing-balance amortization mathematics, and our statistics tools utilize verified sample and population formulas.