Engineering & Conversion Calculators
Unit conversions, electrical calculations, construction quantities, and scientific math — 45 precise tools for engineers, builders, students, and anyone who needs the right number fast.
Unit Converter
Convert between hundreds of units — length, mass, volume, speed, energy, and more.
CM to Inches
Centimeters to inches and back — fast, precise, no rounding errors.
Inches to CM
Inches to centimeters with decimal and fractional input support.
Meters to Feet
Meters to feet and inches — useful for construction, real estate, and travel.
Miles to KM
Miles to kilometers (and reverse) for running, driving, and navigation.
KG to LBS
Kilograms to pounds — for shipping, fitness, cooking, and travel.
Pounds to KG
Pounds to kilograms — precise conversion for any weight measurement.
Liters to Gallons
Liters to US or Imperial gallons for fuel, cooking, and chemistry.
Ounces to Grams
Fluid and weight ounces to grams for cooking, lab work, and shipping.
Temperature Converter
Fahrenheit, Celsius, and Kelvin — with the formula shown for each conversion.
Decimal to Fraction
Convert any decimal to its simplest fractional form — great for measurements.
Fraction to Decimal
Fraction to decimal and percentage — exact or rounded to N decimal places.
Scientific Notation Converter
Convert between standard form and scientific notation with exponent display.
Square Root Calculator
Square roots, cube roots, and nth roots with step-by-step solution.
Exponent Calculator
Any base to any power — includes negative exponents and fractional exponents.
Logarithm Calculator
Natural log, log base 10, and log base N — with change of base formula.
Density Calculator
Solve for density, mass, or volume given two values — for any material.
Molar Mass Calculator
Calculate molecular weight from chemical formula by entering element symbols.
Molarity Calculator
Concentration in mol/L from moles of solute and liters of solution.
pH Calculator
Calculate pH from H⁺ concentration or convert between pH, pOH, and concentration.
Wavelength Calculator
Wavelength from frequency (and vice versa) for any wave — light, sound, radio.
Speed of Sound Calculator
Speed of sound in air by temperature, altitude, and medium.
Amps to Watts
Convert amps to watts (and reverse) using P = IV for AC or DC circuits.
kWh Calculator
Kilowatt-hours consumed by any appliance — and the cost on your electricity bill.
Voltage Drop Calculator
Voltage loss across wire runs by gauge, length, current, and material.
Wire Gauge Calculator
Correct AWG wire size for ampacity, voltage drop, and run length.
Electrical Load Calculator
Total electrical load in amps and watts for circuit planning and panel sizing.
Solar Panel Calculator
System size, output, and payback period for residential solar installations.
Concrete Calculator
Cubic yards or meters needed for slabs, footings, columns, and walls.
Brick Calculator
Number of bricks and mortar needed for any wall by size and bond pattern.
Drywall Calculator
Sheets of drywall needed for rooms — accounting for doors and windows.
Flooring Calculator
Square footage and boxes needed for hardwood, laminate, or tile flooring.
Tile Calculator
Tile quantity and grout for any floor or wall with waste percentage buffer.
Paint Calculator
Gallons of paint needed by room dimensions, coats, and paint coverage rate.
Roofing Calculator
Roofing squares, shingles, and underlayment for pitched roof replacement.
Insulation Calculator
R-value and insulation needed for walls, attic, and floor by climate zone.
Lumber Calculator
Board feet needed for any framing project — wall, deck, floor, or fence.
Gravel Calculator
Tons or cubic yards of gravel, sand, or crushed stone for any area and depth.
Mulch Calculator
Cubic yards of mulch for landscaping beds at any depth and coverage area.
Time Zone Converter
Convert times between any two time zones — with DST handled automatically.
Epoch Converter
Unix timestamp to human-readable date (and reverse) — milliseconds supported.
Date Difference Calculator
Exact days, weeks, months between two dates — excludes or includes weekends.
Days Between Dates
Count calendar days, business days, or hours between any two dates.
Age From Date
Exact age in years, months, and days from any birthdate to today or a target date.
Hours Calculator
Add or subtract times, calculate shift hours, and convert hours to decimal.