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260 calculators across four subjects, plus conversions, charts, guides and printables. Every calculator shows its formula, its derivation and the standard it comes from.
Lumber & framing · Concrete & masonry · Surfaces & finishes · Roofing & exterior · Interior · Landscaping · Outdoor & landscaping · Electrical · Flooring · HVAC & energy
Finance
86Loans & mortgages · Saving & investing · Income & budget · Retirement
- Mortgage Payment
- Compound Interest
- Loan Payment
- Credit Card Payoff
- Savings Goal
- Salary
- Tip
- Fuel Cost
- Gas Mileage
- Unit Price
- Sales Tax
- ROI
- Rent Affordability
- Pay Raise
- Amortization
- APY
- Auto Loan
- Debt-to-Income Ratio
- Deferred Payment and Bond
- Home Affordability
- Interest
- Payment
- CD
- Investment
- Present Value
- Margin and Markup
- Mileage Reimbursement
- Electricity Cost
- 401(k)
- Home Equity
- Car Lease
- Refinance
- Budget
- Depreciation
- VA Loan
- Rent vs Buy
- FHA Loan
- Average Return
- Commission
- HELOC
- Rental Property
- Pension
- Mutual Fund Fee
- Roth IRA
- Traditional vs Roth IRA
- RMD
- Annuity Payout
- Retirement
- Mortgage Payoff
- Student Loan
- Boat Loan
- Business Loan
- Inherited IRA RMD
- Estate Tax
- Debt Consolidation
- Roth Conversion
- Backdoor Roth
- GDP
- Payback Period
- College Cost
- Rebate or Low APR
- VAT
- Simple Interest
- Discount
- Future Value
- Down Payment
- Property Tax
- Overtime Pay
- Capital Gains Tax
- No Tax on Tips
- No Tax on Overtime
- Lottery Tax
- AGI
- 1099 Tax
- W-4 Withholding
- PayPal Fee
- CAGR
- Doubling Time
- Effective Annual Rate
- Price Elasticity
- Net Worth
- CPM
- WACC
- NPS
- Freight Class
- CBM
Body measurements · Body composition · Energy & nutrition · Training & recovery · Pregnancy · Fitness · Dosage · Cooking & kitchen
- Pounds and Ounces Converter
- Stones and Pounds Converter
- BMI
- TDEE
- Body Fat
- Macro
- Ideal Weight
- Water Intake
- Heart Rate Zone
- Calories Burned
- Due Date
- Ovulation
- Calorie Needs
- Weight Loss Timeline
- BMR
- Protein
- Body Surface Area
- Body Shape
- GFR
- One Rep Max
- Period
- Pregnancy Weight Gain
- Sleep
- Army Body Fat
- Conception Date
- Fat Intake
- Lean Body Mass
- Target Heart Rate
- Steps to Miles
- Dog Chocolate Toxicity
- Dog Calorie
- Puppy Weight
- Dog Pregnancy
- A1C
- LDL
- VO2 Max
- FFMI
- Corrected Calcium
- ANC
- Milligrams to Milliliters
- Air Fryer Conversion
Percentages & rates · Geometry · Conversion · Fractions · Algebra · Time & dates · Statistics · Digital · Vehicles · Electricity · Sport · Physics
- Percentage Change
- Diagonal & Rafter Length
- Percentage
- Fraction to Decimal
- GCF and LCM
- Quadratic Formula
- Military Time Converter
- Tire Size
- Height Converter
- Circle
- Tank & Cylinder Volume
- Speed & Pace
- Slope & Grade
- Temperature Converter
- Age
- Fraction
- Simplify Fractions
- Mixed Numbers
- Hours
- Z-Score to P-Value
- Date
- Grade
- Time
- Grams to Cups Converter
- Cone Volume
- Sphere Volume
- Circumference
- Right Triangle
- Arc Length and Sector Area
- Special Right Triangle
- Semicircle
- Pyramid Volume
- Pixels to Inches
- Percent Off
- Ratio
- Volume
- Area
- Distance Formula
- Distance Between Coordinates
- Fuel Consumption Converter
- Horsepower and Torque
- Ohm's Law
- Engine Displacement
- Surface Area
- Slope
- Triangle
- Density
- Rounding
- Exponent
- Logarithm
- Half-Life
- Confidence Interval
- Sample Size
- Probability
- Resistor Colour Code
- Heat Index
- Wind Chill
- Dew Point
- Scientific Notation Converter
- Percent Error
- Number Sequence
- Molarity
- Download Time
- Pythagorean Theorem
- Voltage Drop
- Golf Handicap
- Day Counter
- Oven Temperature Converter
- Completing the Square
- Absolute Value
- Kinetic Energy
- Minutes to Decimal
- Watts to Amps
- kW and kVA to Amps
- Volts to Watts
- mAh to Wh
- Watts to kWh
- Joules to Watts
- Parallel Resistors
- LED Resistor
- Percent Difference
- Difference of Two Squares
- Midpoint
- Dot and Cross Product
- Sig Fig
- Correlation
- Linear Regression
- Binomial
- Interpolation
- Hypergeometric
- Sin Cos Tan
- Inverse Trig
- Law of Sines
- Law of Cosines
- Factorial
- dBm to Watts
- Decibel
- Lumens to Lux
- Velocity
- Momentum
- Work
- Resonant Frequency
- Mass-Energy
Beyond the calculators
- Unit conversions1306 pairsLength, weight, volume and area, with factors from the defining standard.
- Reference charts37 chartsTables to read off or print — inch fractions, roof pitch, mortgage rates.
- Guides9 guidesHow to take the measurement, and what the finished job costs.
- Printable tools3 toolsA ruler, a protractor and a pitch gauge at true size, with calibration.
- Calendars112 pagesYears and months with ISO week numbers and the working days each one holds.
- Date arithmetic383 pagesWhat date falls a given span from today, in calendar days or working days.
- Number bases21 pairsBinary, hexadecimal, text and Roman numerals, each with the conversion worked through.
- Expression calculatorone boxType a sum and get the order it was worked in, not only the total.
- Height percentileages 2-20A child's height against the CDC growth chart parameters, with the z-score.
- Embeddable widgets260 calculatorsPut any calculator on your own page, opening on the numbers you choose.