Free online calculators and converters for everyday life!
Work out loan payments, solve math problems, convert units, and plan home projects. Find practical tools for finance, health, science, and the calculations that come up every day.
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Calculators and tools
Find calculators, converters, and practical tools to simplify everyday tasks, solve math problems, and plan projects.
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Useful categories
Explore finance, health, math, science, construction, and more—all organized to help you find the right tool.
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Free to use
Use free online calculators and converters for everyday questions, quick checks, and practical planning.
t-test Calculator
Use our T-Test Calculator to compute t statistic, p-value, confidence interval, and conclusion for one-sample, Welch, pooled, or paired t-tests.
Ratio Calculator
Simplify, scale and compare ratios or divide a quantity into proportional parts.
Dihybrid Cross (Punnett Square) Calculator
Use the Dihybrid Cross Calculator to generate a 4×4 Punnett square, gametes, genotypes, phenotypes, and probabilities for two traits.
Lean Body Mass Calculator
Use the Lean Body Mass Calculator to estimate lean body mass. Review inputs, results, limitations, safety guidance, and FAQs.
Cycling Calorie Calculator
Estimate calories burned while cycling from body weight, duration, pace and ride conditions, with guidance for interpreting MET-based results.
GCF Calculator
Find the greatest common factor of integers using factor lists, prime factorization or Euclid’s algorithm.
Grams To Ounces Calculator
Use our Grams to Ounces Calculator to convert grams to ounces, ounces to grams, kilograms, milligrams, and troy ounces.
Reading Time Calculator
Use our Reading Time Calculator to estimate how long it takes to read a book, daily pages read, and time needed to finish from pages and reading speed.
Pace Calculator
Use this pace calculator to estimate pace per mile or kilometer, average speed, and projected times. Learn the inputs, formulas, examples, limitations, traini
Decking Calculator
Estimate deck-board rows, pieces and linear length using actual board dimensions, spacing, direction and waste.
All-in-one Home Loan Calculator
Use this all-in-one home loan calculator to calculate estimated payment, cash needed, amortization, affordability indicators, and total loan cost. Review inpu
Age Difference Calculator
Use our Age Difference Calculator to find the exact age gap between two dates of birth in years, months, days, total months, total days, and approximate years.
Percentage to CGPA Calculator
Convert percentage to CGPA using proportional, legacy 9.5, or custom institutional methods, with scale checks and policy guidance.
Child BMI Calculator
Calculate BMI and estimate BMI-for-age percentile for a child or teen, with guidance on measurement and interpretation.
Hair Growth Calculator
Use our Hair Growth Calculator to estimate hair growth, final hair length, or time needed to reach a hair length goal using average growth rates.
Percentage of a Percentage Calculator
Percentage of a percentage calculator to find cumulative percentage and final value from two related percentage changes.
Projectile Motion Calculator
Use our Projectile Motion Calculator to find time of flight, range, maximum height, time to peak, and velocity components from speed, angle, height, and gravity.
APY Calculator
Use this apy calculator to calculate effective annual percentage yield and one-year growth factor. Review inputs, formulas, examples, limitations, and FAQs.
IQ PERCENTILE CALCULATOR
Use our IQ Percentile Calculator to convert an IQ score into percentile rank, percent above, and percent below using SD 15 or SD 16 normal-distribution scales.
Mortgage Calculator with Taxes and Insurance
Use this mortgage calculator with taxes and insurance to calculate estimated total monthly housing payment and component breakdown. Review key inputs,.
Credit Card Interest Calculator
Estimate credit card interest, payoff time, and total repayment cost using balance, APR, payment amount, and compounding assumptions.
Shannon Diversity Index Calculator
Calculate Shannon diversity H′, species richness, total abundance and evenness from species counts using ln, log10 or log2.
BMI Calculator (Body Mass Index)
Use the BMI Calculator to estimate adult body mass index. Review inputs, results, limitations, safety guidance, and FAQs.
t-statistic Calculator
Use our t-Statistic Calculator to compute the t value, degrees of freedom, and standard error for one-sample, two-sample, Welch, pooled, or paired t-tests.
Student Loan Calculator
Use this student loan calculator to calculate estimated payment, payoff time. Review key inputs, formulas, scenarios, limitations, and FAQs.
Weight Gain Calculator
Use the Weight Gain Calculator to estimate a calorie surplus for weight gain. Review inputs, results, limitations, safety guidance, and FAQs.
ABSI (A Body Shape Index) Calculator
Use the ABSI Calculator to estimate A Body Shape Index. Review inputs, results, limitations, safety guidance, and FAQs.
Bird Age Calculator
Use our Bird Age Calculator to convert bird years to human years or human age back to bird age by species or custom lifespan.
CPM Calculator
Use this cpm calculator to calculate cost per thousand impressions, implied cost, or required impressions. Review inputs, formulas, examples, limitations, and
Child Height Predictor
Use the Child Height Predictor to estimate an adult-height estimate for a child. Review inputs, results, limitations, safety guidance, and FAQs.
Wavelength → Energy Calculator
Use our Wavelength to Energy Calculator to find photon energy from wavelength in joules, eV, and kJ/mol using E = hc / λ with vacuum or custom wave speed.
Long Division Calculator
Perform long division with a quotient, remainder and step-by-step divide-multiply-subtract work.
Free AVIF Image Converter
Easily convert AVIF images to JPG, PNG, or WebP formats with our user-friendly tool. Fast, efficient, and free for all your image conversion needs.
Quadratic Formula Calculator
Solve a quadratic equation from coefficients a, b and c and interpret its discriminant and roots.
BMR — Basal Metabolic Rate (Mifflin–St Jeor)
Use the BMR to estimate basal metabolic rate. Review inputs, results, limitations, safety guidance, and FAQs.
Weight Price Comparison Calculator
Use our Weight Price Comparison Calculator to compare two products by price per gram, kilogram, pound, or ounce and find the better value.
Beam Deflection Calculator
Estimate elastic beam deflection for common cantilever and simply supported cases using span, load, elastic modulus, and second moment of area.
Square Footage Calculator
Square Footage Calculator helps you measure room area, total square feet, and material cost quickly with accurate results.
Emergency Fund Calculator
Use this emergency fund calculator to calculate recommended reserve target, current shortfall. Review key inputs, formulas, scenarios, limitations, and FAQs.
Favicon Generator
Turn one logo or image into ICO, PNG and app-icon files with crop, padding, mask and background controls.
Pythagorean Theorem Calculator
Pythagorean Theorem Calculator solves missing sides of a right triangle fast. Use it to find the hypotenuse or any unknown side easily.
Length Converter
Use our Length Converter to convert metric, imperial, US, nautical, survey, and astronomy units including mm, cm, m, km, in, ft, yd, mi, nmi, au, ly, and pc.
Free JPG to PNG Converter
Convert JPG images to PNG format with the embedded converter on this page.
Budget Calculator
Use this budget calculator to calculate monthly surplus or deficit, category totals. Review key inputs, formulas, scenarios, limitations, and FAQs.
Percentage Change Calculator
Use our Percentage Change Calculator to quickly find percent increase or decrease between two values. Instant results, step-by-step breakdown, free & easy to use.
CAGR (Compound Annual Growth Rate) Calculator
Use this cagr (compound annual growth rate) calculator to calculate compound annual growth rate and annualized growth factor. Review inputs, formulas, example
Area Calculator
Calculate the area of common two-dimensional shapes using dimensions in compatible units.
Cat Age Calculator
Use this Cat Age Calculator to estimate your cat’s age in human years using the common 15 / 24 / +4 cat age chart. Includes formula, examples, life stages, and care notes.
Free Fall Calculator
Use our Free Fall Calculator to find time, distance, final velocity, and average speed from height or time with gravity presets and unit conversion.
Minutes to Hours Converter
Minutes to Hours Converter to instantly convert minutes into decimal hours or hours and minutes with clear results.
Cholesterol Units Converter
Convert cholesterol and triglyceride measurements between mg/dL and mmol/L with analyte-specific factors and careful result interpretation.
Data Unit Converter
Convert bits and bytes across decimal and binary storage units while seeing the exact factor used for every result.
Fraction Calculator
Calculate fraction operations, simplify the result and understand common denominators and reciprocals.
mg to mL Calculator
Use our mg to mL Calculator to convert weight and volume using liquid density, preset liquids, or medication concentration in mg/mL or mg/5 mL.
Water Intake Calculator
Estimate a general daily hydration target from body weight, activity and climate, with practical guidance on interpreting the result.
Cholesterol Ratio Calculator
Use the Cholesterol Ratio Calculator to estimate cholesterol ratios. Review inputs, results, limitations, safety guidance, and FAQs.
Surface Area Calculator
Find lateral or total surface area for common three-dimensional solids in square units.
Power Analysis Calculator
Use our Power Analysis Calculator to estimate sample size per group, statistical power, and minimum detectable effect for a two-sample mean test with alpha and standard deviation.
Balance Transfer Calculator
Compare a balance transfer’s fee, promotional period, payment plan, and post-promotion APR against keeping the current credit-card balance.
Drive Time Calculator
Use our Drive Time Calculator to estimate trip time, arrival time, fuel used, fuel cost, and cost per person from distance, speed, and fuel inputs.
Image Color Picker
Pick an exact pixel from an uploaded image and copy its color in HEX, RGB, HSL, HSV, CMYK or OKLCH formats.
Amortization Calculator
Use this mortgage loan amortization calculator to calculate scheduled payment, principal and interest split. Review key inputs, formulas, scenarios,.
Dog Size & Adult Weight Calculator
Use our Dog Size & Adult Weight Calculator to estimate your puppy’s adult weight from age and current weight. Quick size prediction with pet category output.
Fraction to Decimal Calculator
Convert a fraction to terminating or repeating decimal form and understand when rounding is required.
Image Compressor
Compress JPG, PNG, WebP, and SVG images in your browser. Choose JPEG or WebP output, adjust quality, resize dimensions, and download.
Rounding Calculator
Round numbers to a selected place or significant figures and distinguish common rounding methods.
Waist-to-Height Ratio (WHtR) Calculator
Use the Waist-to-Height Ratio Calculator to estimate waist-to-height ratio. Review inputs, results, limitations, safety guidance, and FAQs.
Mixed Number Calculator
Calculate with mixed numbers by converting whole-and-fraction parts to improper fractions and simplifying.
Helium Balloons Calculator
Use our Helium Balloons Calculator to estimate lift per balloon, total helium volume, and how many helium balloons you need to lift a given weight.
Price Elasticity of Demand Calculator
Use this price elasticity of demand calculator to calculate percentage changes, elasticity coefficient, and basic elasticity classification. Review inputs, fo
Scientific Calculator
Evaluate scientific expressions involving powers, roots, logarithms, constants and trigonometric functions.
Running Calorie Calculator
Use this running calorie calculator to estimate estimated calories used during a run. Learn the inputs, formulas, examples, limitations, training tips, and FA
Fraction to Percentage Calculator
Convert fractions to percentages and percentages to simplified fractions. Enter numerator, denominator, or percent to get quick live results.
Creatinine Clearance Calculator
Estimate creatinine clearance with the Cockcroft-Gault equation and review the assumptions, units and limitations behind the result.
Document + PDF Converter
Convert supported documents to or from PDF while checking layout fidelity, fonts, page order, privacy, file limits, and output compatibility.
Stride Length Calculator
Use this stride length calculator to estimate average stride or step length in chosen units. Learn the inputs, formulas, examples, limitations, training tips,
Pre & Post-Money Valuation Calculator
Use this pre & post-money valuation calculator to calculate post-money valuation and implied investor or founder ownership. Review inputs, formulas, examples,
Framing Calculator
Free wall framing calculator: enter wall length/height, stud spacing (16″/24″ o.c.) & openings to get studs, plates, headers, sheathing and cost. Metric/imperial with waste %, steps & PDF.
mcg to IU Converter
Convert between micrograms and international units using the correct vitamin and chemical form, with label-reading and safety guidance.
Average Percentage Calculator
Average percentage calculator to find simple or weighted averages of multiple percentages with quick, accurate results.
Bikini Calculator
Use our Bikini Calculator to estimate your body shape from bust, waist, high hip, and hip measurements, then get bikini style suggestions that fit your shape.
Harris-Benedict Calculator (Basal Metabolic Rate)
Use the Harris-Benedict Calculator to estimate basal metabolic rate. Review inputs, results, limitations, safety guidance, and FAQs.
Adjusted Body Weight Calculator
Use the Adjusted Body Weight Calculator to estimate adjusted body weight. Review inputs, results, limitations, safety guidance, and FAQs.
Exponent Calculator
Exponent Calculator helps you solve powers, positive and negative exponents, and exponential values quickly with clear, accurate results.
Percentage Increase Calculator
Find the percentage increase between two numbers. Enter original and new values to get % increase, change amount, and final value. Reverse solve from % too. Instant steps & PDF.
GPA calculator
Calculate semester GPA and estimate cumulative GPA from course grade points and credit hours, with clear formulas and policy guidance.
Weighted Grade Calculator
Calculate a weighted course grade from category percentages and weights, including the normalized grade so far and remaining weight.
Salary to Hourly Calculator
Use this salary to hourly calculator to calculate equivalent monthly, weekly, daily, and hourly gross pay. Review inputs, formulas, examples, limitations, and
Investment Calculator
Use this investment calculator to calculate projected future value, total contributions. Review key inputs, formulas, scenarios, limitations, and FAQs.
Roofing Shingle Calculator
Estimate sloped roof area, roofing squares and bundles from footprint, pitch and a complexity allowance.
Waist-to-Height & Waist-to-Hip Ratio Calculator
Use the Waist-to-Height & Waist-to-Hip Ratio Calculator to estimate waist-to-height and waist-to-hip ratios. Learn inputs, limits, and FAQs.
Theoretical Yield Calculator
Theoretical Yield Calculator to find the maximum product yield from stoichiometry, limiting reagent, and molar relationships.
FFMI Calculator (Fat-Free Mass Index)
Use the FFMI Calculator to estimate fat-free mass index. Review inputs, results, limitations, safety guidance, and FAQs.
Simple Loan Calculator
Use this simple loan calculator to calculate simple interest, total repayment, and periodic payment. Review inputs, formulas, examples, limitations, and FAQs.
Ramp Calculator
Use our Ramp Calculator to find ramp slope angle, grade percent, run, and ramp length from rise, ratio, or accessibility ramp presets.
Topsoil Calculator
Estimate topsoil volume, bags or mass from the measured area, fill depth and the supplier’s product information.
Percentage Decrease Calculator
Percentage decrease calculator to find the drop between two values or solve the missing initial, final, or decrease percentage fast.
Steps to Miles Calculator
Use this steps to miles calculator to estimate estimated distance in miles and kilometers. Learn the inputs, formulas, examples, limitations, training tips, a
Body Shape Calculator
Body Shape Calculator helps you identify your body type from key measurements and understand which shape category fits you best.
Stock Calculator
Use this stock calculator to calculate cost basis, proceeds, gain or loss, and percentage return. Review inputs, formulas, examples, limitations, and FAQs.