100% FreeAccurate, instant calculators built on verified formulas. No account needed, no ads interrupting your work, and all calculations stay private in your browser.
Every tool is optimized for accuracy, speed, and intuitive use — with formula explanations and FAQs built in.
Calculate what X% of Y is, find what percent one number is of another, and compute percent change, increase, and decrease — with step-by-step formula explanations.
percentage calculator, percent change, how to calculate percentage, percentage increase
Calculate Body Mass Index using the official WHO formula. Supports metric (kg/cm), imperial (lbs/inches), and UK stone units. Includes BMI chart and classification.
bmi calculator, body mass index, healthy weight, bmi chart
Calculate semester GPA, cumulative GPA, and weighted GPA on 4.0 or 5.0 scales. Includes final grade calculator and CGPA to percentage conversion.
gpa calculator, college gpa, weighted gpa, cumulative gpa, final grade calculator
Calculate future value with daily, monthly, quarterly, semi-annual, or annual compounding. Includes APY calculation and investment growth chart.
compound interest calculator, investment calculator, future value, apy calculator
Calculate your monthly loan payment (EMI) and view the full amortization schedule with principal vs. interest breakdown for any loan or mortgage.
emi calculator, loan calculator, monthly payment calculator, amortization schedule
Find your exact age in years, months, weeks, and days. Accounts for leap years and calculates countdown to your next birthday.
age calculator, how old am i, birthday calculator, date of birth calculator
Convert between units of length, mass, temperature, speed, area, volume, and digital storage using internationally standardized SI conversion factors.
unit converter, length conversion, weight conversion, temperature converter
Calculate simple ROI, annualized return (CAGR), real estate cap rate, cash-on-cash return, and marketing ROI in one comprehensive tool.
roi calculator, return on investment, annualized return, cagr calculator
Calculate sales tax amount and total price for any US state or custom rate. Works for both adding tax to a price and removing tax from a total.
sales tax calculator, tax calculator, us sales tax, add tax to price
Calculate VAT (Value Added Tax) for any rate — add VAT to a net price or remove VAT from a gross price. Supports UK (20%), EU, and custom rates.
vat calculator, value added tax, vat calculator uk, net to gross, gross to net
CalcNest was built for people who need reliable answers without paywalls, registration walls, or invasive data collection.
Answers appear instantly as you type — no page reloads, no waiting.
All calculations happen in your browser. Your data is never sent to our servers.
Works perfectly on every smartphone, tablet, and desktop — no app needed.
Every formula is sourced from authoritative bodies: WHO, CDC, BIPM, CFA Institute.
Whether you're a student calculating your GPA before finals, a homeowner estimating mortgage payments, a professional computing investment ROI, or simply figuring out a sales tax or tip — CalcNest delivers the right answer in seconds, with the formula shown every step of the way.
Everything you need to know about our free online calculators.
CalcNest provides a suite of free online calculators including: Percentage Calculator (percent change, increase, decrease), BMI Calculator (WHO classification, metric & imperial), GPA Calculator (college, high school, weighted, cumulative), Compound Interest Calculator, Loan EMI Calculator (amortization schedule), Age Calculator, ROI Calculator, Unit Converter, Sales Tax Calculator, and VAT Calculator.
Yes, every tool on CalcNest is 100% free. No account, no subscription, and no credit card is required. The site is supported by non-intrusive Google AdSense advertising, which keeps all tools permanently free.
All CalcNest calculators are based on verified formulas from authoritative sources: BMI uses WHO classification, unit conversions follow BIPM SI standards (2019), financial formulas follow CFA Institute methodology, and academic tools follow AACRAO guidelines. Results are computed in real-time with high numerical precision.
No. All calculations are performed entirely in your web browser using JavaScript. Your inputs — weight, height, income, investment amounts, or any other values — are never transmitted to our servers, stored, or shared with third parties. Calculations run locally on your device.
Yes. CalcNest is fully responsive and optimised for mobile, tablet, and desktop devices. All calculators work seamlessly on iOS (iPhone/iPad) and Android without requiring any app installation.
Percentage increase = ((New Value − Old Value) / Old Value) × 100. For example, if a price rises from $50 to $65: ((65 − 50) / 50) × 100 = 30% increase. Use our free Percentage Calculator above for instant results.
Choose a free calculator below and get accurate results instantly.