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A short list of useful finance, mortgage, health, and home-project tools. Browse the complete directory below for all 133 calculators available now.

Dates & timeWork Days CalculatorCalculate Dates & timeDate From Days CalculatorCalculate Dates & timeTime Card CalculatorCalculate Dates & timeCountdown CalculatorCalculate Everyday mathematicsPercentage CalculatorCalculate Everyday mathematicsFraction CalculatorCalculate Dates & timeDays Between Dates CalculatorCalculate Dates & timeTime Zone ConverterCalculate Everyday paymentsDiscount CalculatorCalculate Everyday paymentsBill Split CalculatorCalculate Unit convertersLength ConverterCalculate Unit convertersTemperature ConverterCalculate

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Yard & landscape

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Calories & nutrition

Mortgage & home buying

Property investing

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Money & mortgagePayments, savings, income, and investing

Mortgage & home buyingConventional, FHA, VA, affordability, and refinancing12 Debt & interestPayoff plans and straightforward interest comparisons5 Income & paySalary, overtime, take-home pay, and startup costs4 Investing & retirementGrowth, inflation, 401(k), and retirement targets8 Property investingRental income, cap rate, cash flow, and flip profit11 Self-employed taxes1099 income, quarterly payments, deductions, and reserves9 Small-business financingTerm loans, SBA loans, equipment, and credit lines4 Business planning & pricingStartup capital, break-even, margin, and markup4 Debt consolidation & borrowing readinessConsolidation payments, interest, and debt-to-income ratios2

Health & fitnessWeight, nutrition, heart rate, and sleep

Pregnancy healthPre-pregnancy BMI and pregnancy weight-gain ranges2 Body weight & compositionReference weight, body fat, and weight-loss planning4 Calories & nutritionBMR, TDEE, calorie targets, macros, and muscle gain5 Daily wellnessHydration, resting heart rate, and sleep balance3

Home & projectsMaterials, measurements, and project planning

Painting projectsInterior rooms, exterior walls, coats, and coverage2 Floors & surfacesTile and flooring coverage, packages, and waste2 Construction materialsConcrete, gravel, drywall, and roofing quantities4 Yard & landscapeMulch depth, lawn area, rolls, and pallets2

Grades & GPACourse grades, weighted exams and credit-based GPA

Grades & GPAGPA Calculator, College GPA Calculator, Semester GPA Calculator9

Dates & timeCalendar days, shifts, birthdays and UTC offsets

Dates & timeDays Between Dates Calculator, Work Days Calculator, Date From Days Calculator13

Everyday mathematicsPercentages, fractions, powers and integer calculations

Everyday mathematicsPercentage Calculator, Average Calculator, Fraction Calculator10

Plane geometryTriangles, rectangles and circle measurements

Plane geometryTriangle Calculator, Rectangle Calculator, Circle Calculator3

Unit convertersMetric, customary, temperature and number representations

Unit convertersLength Converter, Weight Converter, Volume Converter8

Technical utilitiesIPv4 networks, local passwords and color codes

Technical utilitiesSubnet Calculator, CIDR Calculator, Password Generator4

Everyday paymentsDiscounts, gratuities and equal bill shares

Everyday paymentsDiscount Calculator, Tip Calculator, Bill Split Calculator3

Complete tool directory

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133 tools organized around real tasks, with focused collections that help you choose the right calculator.

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Money & mortgageMortgage extra payment calculatorCalculate Money & mortgageBi-weekly mortgage calculatorCalculate Money & mortgageMortgage calculator with PMI & taxesCalculate Money & mortgageHome affordability calculatorCalculate Money & mortgageRental property ROI calculatorCalculate Money & mortgageRent vs buy calculatorCalculate Money & mortgageCredit card payoff calculatorCalculate Money & mortgageDebt snowball & avalanche calculatorCalculate Money & mortgageRetirement savings calculatorCalculate Money & mortgageCompound interest calculatorCalculate Money & mortgageSimple interest calculatorCalculate Money & mortgageSmall business startup cost calculatorCalculate Money & mortgageHourly wage to annual salary calculatorCalculate Money & mortgageOvertime pay calculatorCalculate Money & mortgageNet income take-home calculatorCalculate Money & mortgageInvestment return calculatorCalculate Money & mortgage401k contribution calculatorCalculate Money & mortgageInflation adjusted calculatorCalculate Money & mortgage401(k) vs Roth IRA calculatorCalculate Money & mortgageInvestment compound return calculatorCalculate Money & mortgageMortgage refinance break-even calculatorCalculate Money & mortgageStudent loan refinance calculatorCalculate Money & mortgageFHA mortgage payment calculatorCalculate Money & mortgageVA home loan payment calculatorCalculate Money & mortgageRental property cap rate calculatorCalculate Money & mortgageRental property cash flow calculatorCalculate Money & mortgageShort-term rental income calculatorCalculate Money & mortgageHouse flipping profit calculatorCalculate Money & mortgageSelf-employed tax estimatorCalculate Money & mortgageFreelancer quarterly tax calculatorCalculate Money & mortgage1099 tax calculatorCalculate Money & mortgageLLC tax calculatorCalculate Money & mortgageSelf-employment tax deduction calculatorCalculate Money & mortgageGig economy tax calculatorCalculate Money & mortgageSafe harbor tax calculatorCalculate Money & mortgageFreelance tax set-aside calculatorCalculate Money & mortgageSmall business loan calculatorCalculate Money & mortgageSBA loan calculatorCalculate Money & mortgageEquipment financing calculatorCalculate Money & mortgageBusiness line of credit calculatorCalculate Money & mortgageBusiness startup break-even calculatorCalculate Money & mortgageSmall business profit margin calculatorCalculate Money & mortgageMarkup and margin calculatorCalculate Money & mortgageStartup capital calculatorCalculate Money & mortgageDebt consolidation calculatorCalculate Money & mortgageDebt-to-income ratio calculatorCalculate Money & mortgageBusiness expense deduction calculatorCalculate Money & mortgageNet worth calculator for millennialsCalculate Money & mortgageMortgage escrow payment calculatorCalculate Money & mortgageMortgage amortization schedule calculatorCalculate Money & mortgageHome purchase closing cost calculatorCalculate Money & mortgageRental property vacancy rate calculatorCalculate Money & mortgageShort-term rental profit margin calculatorCalculate Money & mortgageBuy-and-hold real estate ROI calculatorCalculate Money & mortgageMultifamily rental cash flow calculatorCalculate Money & mortgageHouse flipping rehab budget calculatorCalculate Money & mortgageMortgage points break-even calculatorCalculate Money & mortgageHELOC payoff calculatorCalculate Money & mortgageRental property tax deduction calculatorCalculate Health & fitnessPregnancy BMI calculatorCalculate Health & fitnessPregnancy weight gain calculatorCalculate Health & fitnessIdeal weight calculator for menCalculate Health & fitnessIdeal weight calculator for womenCalculate Health & fitnessTDEE calculator for athletesCalculate Health & fitnessCalorie deficit calculatorCalculate Health & fitnessMacros calculator for keto dietCalculate Health & fitnessBody fat percentage calculatorCalculate Health & fitnessBasal metabolic rate BMR calculatorCalculate Health & fitnessWeight loss goal calculatorCalculate Health & fitnessMuscle gain calorie calculatorCalculate Health & fitnessWater intake calculatorCalculate Health & fitnessResting heart rate calculatorCalculate Health & fitnessSleep debt calculatorCalculate Home & projectsPaint calculatorCalculate Home & projectsExterior paint calculatorCalculate Home & projectsTile calculatorCalculate Home & projectsMulch calculatorCalculate Home & projectsConcrete calculatorCalculate Home & projectsSod calculatorCalculate Home & projectsGravel calculatorCalculate Home & projectsDrywall calculatorCalculate Home & projectsFlooring calculatorCalculate Home & projectsRoof shingles calculatorCalculate Grades & GPAGPA CalculatorCalculate Grades & GPACollege GPA CalculatorCalculate Grades & GPASemester GPA CalculatorCalculate Grades & GPACGPA CalculatorCalculate Grades & GPAFinal Grade CalculatorCalculate Grades & GPARequired Grade CalculatorCalculate Grades & GPAExam Weighted Grade CalculatorCalculate Grades & GPAGrade CalculatorCalculate Grades & GPAAssignment Grade CalculatorCalculate Everyday mathematicsPercentage CalculatorCalculate Everyday mathematicsAverage CalculatorCalculate Everyday mathematicsFraction CalculatorCalculate Everyday mathematicsSquare Root CalculatorCalculate Everyday mathematicsRatio CalculatorCalculate Everyday mathematicsGCD & LCM CalculatorCalculate Everyday mathematicsExponent CalculatorCalculate Everyday mathematicsRounding CalculatorCalculate Everyday mathematicsPrime Factorization CalculatorCalculate Everyday mathematicsFactorial CalculatorCalculate Plane geometryTriangle CalculatorCalculate Plane geometryRectangle CalculatorCalculate Plane geometryCircle CalculatorCalculate Unit convertersLength ConverterCalculate Unit convertersWeight ConverterCalculate Unit convertersVolume ConverterCalculate Unit convertersSpeed ConverterCalculate Unit convertersArea ConverterCalculate Unit convertersTemperature ConverterCalculate Unit convertersBinary Hex Decimal ConverterCalculate Unit convertersRoman Numeral ConverterCalculate Technical utilitiesSubnet CalculatorCalculate Technical utilitiesCIDR CalculatorCalculate Technical utilitiesPassword GeneratorCalculate Technical utilitiesColor Code ConverterCalculate Everyday paymentsDiscount CalculatorCalculate Everyday paymentsTip CalculatorCalculate Everyday paymentsBill Split CalculatorCalculate Dates & timeDays Between Dates CalculatorCalculate Dates & timeWork Days CalculatorCalculate Dates & timeDate From Days CalculatorCalculate Dates & timeAge CalculatorCalculate Dates & timeBirthday Countdown CalculatorCalculate Dates & timeDay of the Week CalculatorCalculate Dates & timeWeek Number CalculatorCalculate Dates & timeHours CalculatorCalculate Dates & timeTime Duration CalculatorCalculate Dates & timeTime Card CalculatorCalculate Dates & timeTime Zone ConverterCalculate Dates & timeCountdown CalculatorCalculate Dates & timeUnix Timestamp ConverterCalculate

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Browse by task or search the tool name. Topic collections compare inputs and conventions; the detailed explanations provide formulas, worked examples and limitations.

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Can a grade result replace an official transcript?

Grade tools calculate from your credits, scores and weights. Your school’s point scale, repeat-course policy and rounding rule still determine the official result.

What should I check before converting units?

Check the dimension and definition: area versus length, U.S. versus imperial volume, or a temperature reading versus a temperature change. Keep intermediate precision before final rounding.

Can I use tools offline or embed them?

The 50 phase-one calculators support standalone embedding and an offline directory. Load the offline resources online first. Embedded inputs stay in the browser, and attribution is optional.

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