ToolsRift studio · 126 tools
Calc & Convert Studio — free calculators and converters that run in your browser
133 free maths calculators, unit converters and date tools. Exact fractions, defined conversion factors and time-zone-safe date maths.
Start here
-
Age Calculator
Calculate exact age in years, months and days from date of birth, with next birthday countdown
-
Advanced Percentage Calculator
Comprehensive percentage operations.
-
Percentage Change Calculator
Percent increase or decrease between an old and new value, with absolute difference.
-
Date Difference Calculator
Days, weeks, months and years between any two dates
-
Length Converter
Convert km, m, cm, mm, miles, feet, inches, nautical miles
-
Weight / Mass Converter
Convert kg, g, pounds, ounces, stones, metric tons and more
-
Temperature Converter
Convert Celsius, Fahrenheit, Kelvin, Rankine and Réaumur
All Calc tools
-
Acceleration Converter
m/s², g, ft/s², Gal.
-
Angle Converter
Convert degrees, radians, gradians, arcminutes and arcseconds
-
Area Converter
Convert m², km², acres, hectares, square feet and miles
-
Blood Glucose Converter
Convert blood sugar readings between mg/dL and mmol/L using the standard glucose factor of 18.0182.
-
Bra Size Converter
US, UK, EU, FR/BE, IT, AU/NZ.
-
Capacitance Converter
F, µF, nF, pF.
-
Clothing Size Converter
US/UK/EU/IT/AU chart (men/women).
-
Color Temperature ↔ Mired Converter
Convert Kelvin color temperature to and from mireds (mired = 1,000,000 ÷ K) for photography and lighting gel calculations.
-
Cooking Measurement Converter
Convert cups, tablespoons, teaspoons, fluid oz, mL and liters
-
Current Converter
A, mA, µA, kA.
-
Data Storage Converter
Convert bits, bytes, KB, MB, GB, TB, Mbps and Kbps
-
Data Transfer Rate Converter
Convert bits/s, Mbps, Gbps, bytes/s, MB/s and GB/s bandwidth units
-
Decimal to Fraction Converter
Convert terminating or repeating decimals to a simplified fraction, mixed number, and GCD.
-
Density Converter
kg/m³, g/cm³, lb/ft³ and more.
-
Dynamic Viscosity Converter
Convert pascal-second, poise, centipoise, micropoise and lbf·s/ft²
-
Electric Charge Converter
Convert coulombs, ampere-hours, mAh, faraday, abcoulomb and statcoulomb
-
Energy Converter
Convert Joules, kWh, BTU, calories, electronvolts and ergs
-
Flow Rate Converter
Convert m³/s, L/min, GPM, CFM and other volumetric flow rates
-
Force Converter
Newtons, kN, lbf, kp, dyne.
-
Frequency ↔ Wavelength Converter
Convert between frequency (Hz, kHz, MHz, GHz) and electromagnetic wavelength using λ = c/f with the exact speed of light.
-
Frequency Converter
Convert Hz, kHz, MHz, GHz, RPM and radians per second
-
Fuel Economy Converter
Convert MPG (US/UK), km/L and L/100km for fuel efficiency
-
Illuminance Converter
lux, foot-candle, phot, nox.
-
Inductance Converter
H, mH, µH, nH.
-
Kinematic Viscosity Converter
Convert m²/s, mm²/s, cm²/s, stokes, centistokes and ft²/s
-
Length Converter
Convert km, m, cm, mm, miles, feet, inches, nautical miles
-
Luminance Converter
cd/m², nit, ft-L, stilb, lambert.
-
Magnetic Field Converter
Convert tesla, millitesla, microtesla, gauss, milligauss and kilogauss
-
Magnetic Flux Converter
Wb, Mx, T·m², V·s.
-
Number to Words
Convert up to 1 trillion to English words.
-
Oven Gas Mark Converter
Convert oven gas marks (¼–10) to Fahrenheit and Celsius with a full baking temperature reference table.
-
Paper Size Converter
A/B + US sizes, dimensions + visuals.
-
Power Converter
Convert Watts, kilowatts, horsepower, BTU/hr and more
-
Pressure Converter
Convert Pa, kPa, bar, PSI, atm, Torr and inches of mercury
-
Radiation Converter
Convert Sievert, Gray, rem, rad, Becquerel, Curie and more
-
Resistance Converter
Ω, kΩ, MΩ, µΩ.
-
Ring Size Converter
Convert ring sizes across US, UK, EU/ISO and inside diameter/circumference in millimetres.
-
Roman Numeral Converter
Convert whole numbers (1–3999) to Roman numerals and parse Roman numerals back to integers with canonical-form validation.
-
Running Pace Converter
Convert running pace between min/km, min/mi, km/h, mph and swim/row pace
-
Shoe Size Converter
US/UK/EU/JP/CN/AU/BR.
-
Speed Converter
Convert m/s, km/h, mph, knots, Mach and speed of light
-
Temperature Converter
Convert Celsius, Fahrenheit, Kelvin, Rankine and Réaumur
-
Time Converter
Convert nanoseconds to centuries — all time units covered
-
Tire Pressure Converter
Convert tire and general pressure between PSI, bar, kPa, standard atmospheres, kgf/cm² and mmHg.
-
Torque Converter
N·m, lb·ft, lb·in, kg·m.
-
Typography Converter
pt, px, em, rem, mm, cm by DPI.
-
Viscosity Converter
Dynamic + kinematic viscosity units.
-
Voltage Converter
V, mV, kV, MV.
-
Volume Converter
Convert liters, gallons, cubic meters, cups, fluid ounces
-
Weight / Mass Converter
Convert kg, g, pounds, ounces, stones, metric tons and more
-
Wire Gauge Converter
AWG ↔ mm ↔ mm² with full table.
-
2D Vector Calculator
Magnitude, dot product, 2D cross (scalar), sum, and angle between two 2D vectors.
-
3D Distance Calculator
Euclidean distance between two points in 3D space with the full √((Δx)²+(Δy)²+(Δz)²) breakdown.
-
3D Vector Calculator
Magnitudes, dot product, cross product vector, and angle between two 3D vectors.
-
Angle Calculator
Triangle, supplementary, and complementary angles.
-
Arc Length Calculator
Arc length and sector area from radius and angle.
-
Area Calculator
Area for 10 common shapes with formula and diagram.
-
Circle Calculator
Full circle report from radius, diameter, circumference, or area — solves all four properties at once with formulas.
-
Cone Calculator
Cone volume, slant height, lateral surface, base area, and total surface area from radius and height.
-
Coordinate Line Properties
Slope, distance, midpoint, and equation together.
-
Cylinder Calculator
Cylinder volume, base area, lateral surface, and total surface area from radius and height with formulas.
-
Distance Between Points
Distance from two coordinates with steps.
-
Ellipse Calculator
Ellipse area, Ramanujan perimeter, eccentricity, and focal distance from the two semi-axes.
-
Golden Ratio Calculator
Golden dimensions from one measurement.
-
Midpoint Calculator
Midpoint between two coordinates.
-
Perimeter Calculator
Perimeter/circumference for 10 shapes with formula and diagram.
-
Pythagorean Calculator
Solve right triangle sides with steps and diagram.
-
Regular Polygon Calculator
Regular polygon interior/exterior angle, perimeter, apothem, area, and circumradius from side count and length.
-
Slope & Line Equation
Slope, intercept, and line equation from two points.
-
Sphere Calculator
Sphere volume, surface area, diameter, and great-circle circumference from the radius with exact formulas.
-
Surface Area Calculator
Surface area of 8 3D shapes with formula.
-
Trapezoid Calculator
Trapezoid area, median (midsegment), and perimeter from the two parallel sides, height, and legs.
-
Triangle Solver
Solve any triangle from three sides (SSS), SAS, ASA, AAS or SSA: all sides and angles, area, perimeter and type, with both answers in the ambiguous case.
-
Volume Calculator
Volume of 8 3D shapes with formula.
-
Advanced Fraction Calculator
Fraction operations with steps.
-
Advanced Percentage Calculator
Comprehensive percentage operations.
-
Aspect Ratio Calculator
Find ratio and equivalent dimensions.
-
Binary Arithmetic
Binary + - × ÷ operations.
-
Boolean Algebra
Simplify boolean expression and truth table.
-
Complex Number Calculator
Add/subtract/multiply/divide complex numbers.
-
Cubic Equation Solver
Solve ax³+bx²+cx+d=0 for all three roots (real and complex) using the discriminant and Cardano/trigonometric method.
-
Factorial Calculator
Factorial up to 20! with expansion.
-
Fibonacci Calculator
Generate sequence or nth term.
-
GCD & LCM Calculator
Compute GCD/LCM for 2–5 numbers with steps.
-
ISO Week Number
Find the ISO 8601 week number for any date, plus the day of year and week-year
-
Logarithm Calculator
Log base 2, 10, e, custom.
-
Matrix Calculator
2x2/3x3 add, multiply, determinant, inverse, transpose.
-
Modulo Calculator
Modulo with quotient and remainder.
-
Number Base Converter
Convert bases 2,8,10,16 and custom.
-
Percent Error Calculator
Percent error between a measured/experimental value and the true/theoretical value, with absolute error.
-
Percentage Change Calculator
Percent increase or decrease between an old and new value, with absolute difference.
-
Prime Checker
Check primality and nearest primes.
-
Prime Factorization
Prime factors with exponents.
-
Proportion Solver
Solve a/b = c/d for the missing term via cross multiplication. Leave one box blank to find x.
-
Quadratic Solver
Solve ax²+bx+c with discriminant and roots.
-
Ratio Simplifier
Simplify and generate equivalent ratios.
-
Rounding Calculator
Round decimals, sig figs, or nearest.
-
Scientific Notation
Convert standard <-> scientific.
-
Sequence Calculator
Nth term and sum for arithmetic/geometric.
-
Set Theory Calculator
Union, intersection, difference + Venn text.
-
Significant Figures
Round to sig figs with explanation.
-
Trigonometry Calculator
sin cos tan and inverse in deg/rad.
-
Truth Table Generator
Generate truth table for boolean expression.
-
Mean, Median & Mode Calculator
Mean, median, mode, range, variance and standard deviation from a list of numbers.
-
Permutation & Combination Calculator
Compute nPr and nCr with n! and r!, using iterative products for large-number safety.
-
Z-Score Calculator
Standard score z=(x−μ)/σ with an approximate normal-distribution percentile.
-
Add or Subtract Days
Add or subtract days from any date and get the exact resulting date and weekday
-
Age Calculator
Calculate exact age in years, months and days from date of birth, with next birthday countdown
-
Business Days Calculator
Count working days (Mon–Fri) between two dates, excluding weekends
-
Countdown Timer
Set minutes and seconds and count down with start, pause and reset controls
-
Date Difference Calculator
Days, weeks, months and years between any two dates
-
Day of the Week Finder
Find what day of the week any date falls on using Zeller
-
Days in Month Calculator
Find how many days are in any month and year, including leap-year February
-
Days Until Calculator
Count down the days remaining until a birthday, exam, wedding or any event
-
Easter Sunday Date Finder
Calculate the exact date of Easter Sunday for any year using the Computus algorithm
-
Leap Year Checker
Check whether any year is a leap year and see the next and previous leap years
-
Moon Phase Calculator
See the moon phase, illumination and lunar age for any date with an emoji icon
-
Online Stopwatch
Precise stopwatch with lap times, start, pause and reset — works fullscreen
-
Pomodoro Timer
Focus timer with 25-minute work sessions and 5-minute breaks for productivity
-
Weekday Counter
Count how many Mondays, Fridays or any weekday fall between two dates
-
World Clock & Time Zone Converter
See the current time in major cities worldwide and convert any time between time zones
-
Electricity Cost Calculator
Appliance electricity bill estimate.
-
Fuel Cost Calculator
Trip fuel cost estimate.
-
Ohm's Law Calculator
Solve V, I, R or P.
-
PPI/DPI Calculator
Pixels per inch from resolution/size.
-
Typing Speed Test
Test your typing speed in WPM with live accuracy tracking — retry as many times as you want
No tools match. Try another word, or .
About Calc & Convert Studio
Calc and Convert Studio has 133 tools for numbers, units and dates. School and work maths sits next to practical converters: the Percentage Calculator handles the usual what-percent-of questions, the Fraction Calculator keeps answers as exact fractions, and the Quadratic Solver shows real and complex roots. The Length Converter and Temperature Converter cover the everyday units, while specialist converters handle torque, wire gauge, clothing sizes and paper sizes. The Age Calculator and date-difference tools round it out.
Accuracy is the point of this studio. Fraction and big-number tools use exact arithmetic rather than floating point, so 1/3 + 1/6 gives 1/2 instead of a long decimal. Conversion factors are the official definitions, such as the 1959 international yard and pound or the 231-cubic-inch US gallon. Date tools count days with integer calendar maths, so your device's time zone or a daylight-saving change cannot shift the answer by a day. All of it runs in the browser.
Frequently asked questions
Why does the fraction calculator not show decimals?
Which gallon and ton do the converters use?
Does the age calculator handle leap-year birthdays?
Do I need to be online to use the calculators?
Where are the cooking and fuel economy converters?
Other studios
- PDF StudioMerge, compress, sign and convert PDFs on your device.
- Image StudioResize, compress, convert and clean up images privately.
- Media StudioTrim, convert and record video and audio in the browser.
- Money StudioLoans, savings, tax and seller fees, with the maths shown.
- Health StudioCalories, BMI, heart-rate zones and sleep, explained.
- Developer StudioFormat, validate, convert and decode — locally, instantly.
- Design StudioColours, gradients, CSS and SVG you can copy straight in.
- Writing StudioCount, clean, transform and draft text without distractions.
- Office & Business StudioInvoices, documents, charts and policies, tidy and fast.
- Study StudioFlashcards, citations, quizzes and revision timers.
- Security StudioPasswords, hashes and ciphers generated on your device.
- Fun StudioWheels, dice, pickers and fancy text for when chance decides.