🧮 Everyday Converters & Calculators

44 free tools, all running in your browser. No sign-up.

🧮 Length Converter

Convert between mm, cm, m, km, inches, feet, yards, miles, and nautical miles — type once, see every unit at once.

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🧮 Weight / Mass Converter

Convert between mg, g, kg, metric tons, ounces, pounds, stone, and US tons instantly in your browser.

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🧮 Temperature Converter

Convert between Celsius, Fahrenheit, Kelvin, and Rankine with correct absolute-zero validation.

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🧮 Area Converter

Convert between mm², cm², m², hectares, km², square inches/feet/yards/miles, and acres.

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🧮 Volume Converter

Convert between mL, L, m³, US and Imperial fluid units — with US vs Imperial gallon sizes clearly distinguished.

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🧮 Speed Converter

Convert between m/s, km/h, mph, knots, ft/s, and Mach (sea-level approximation).

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🧮 Pressure Converter

Convert between Pascal, kPa, MPa, bar, PSI, atmospheres, mmHg, and torr.

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🧮 Energy Converter

Convert between joules, calories, food Calories, watt-hours, kilowatt-hours, BTU, and foot-pounds.

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🧮 Angle Converter

Convert between degrees, radians, gradians, and degrees-minutes-seconds (DMS) format.

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🧮 Torque & Force Converter

Convert force (Newton, kgf, lbf, dyne) and torque (N·m, kgf·m, lb-ft, lb-in) in one page.

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🧮 Fuel Economy Converter

Convert between MPG (US), MPG (Imperial), L/100km, and km/L, accounting for different gallon sizes.

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🧮 Data Storage Converter

Convert between bits, bytes, KB/MB/GB/TB — shown in both binary (1024-based) and decimal (1000-based) units side by side.

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🧮 Typography Unit Converter

Convert between px, pt, em, and rem with an adjustable base font size and DPI.

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🧮 Cooking Measurement Converter

Convert between cups, tablespoons, teaspoons, mL, fl oz, and grams for over 20 common ingredients.

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🧮 Shoe Size Converter

Convert shoe sizes between US, UK, EU, and cm for men's, women's, and kids' sizing.

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🧮 Clothing Size Converter

Convert clothing sizes between US, UK, EU, and international (XS-XXL) for men's and women's items.

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🧮 Paper Size Reference

Searchable reference of ISO A/B series and North American paper sizes with exact dimensions in mm and inches.

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🧮 Screen Size / PPI Calculator

Calculate pixels-per-inch from a screen's diagonal size and resolution, or solve for diagonal size from a target PPI.

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🧮 Aspect Ratio Calculator

Simplify a width/height into its aspect ratio, or solve for a missing dimension given a target ratio.

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🧮 Print DPI Calculator

Calculate print resolution (DPI) from pixel dimensions and print size, or the pixels needed for a target DPI.

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🧮 Paper Weight (GSM) Calculator

Convert between GSM and US paper weight (lb), correctly per paper category — Bond, Text, Cover, or Index.

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🧮 Unit Price Comparator

Compare multiple products by price per standard unit (per 100g, per liter, per item) to find the better deal.

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🧮 Time Zone Converter

Convert a date and time from one time zone to several others at once, with correct DST handling.

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🧮 Date Difference Calculator

Calculate the difference between two dates in days, weeks, hours, and a calendar-aware years/months/days breakdown.

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🧮 Age Calculator

Calculate exact age in years, months, and days as of any date, plus total days lived and day of the week born.

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🧮 Days Until / Countdown Calculator

Get a live countdown (or elapsed time) to or from any target date and time.

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🧮 Week Number Calculator

Find a date's ISO-8601 week number and the US (Sunday-start) week number side by side.

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🧮 Business Days Calculator

Count business days between two dates (with optional holiday exclusions), or add business days to a start date.

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🧮 Roman Calendar Date Converter

Convert a Gregorian date to the Roman Kalends/Nones/Ides naming system, and back.

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🧮 Sleep Cycle Calculator

Find the best bedtime or wake-up time based on 90-minute sleep cycles — a general estimate, not medical advice.

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🧮 Percentage Calculator

Four calculators in one: X% of Y, X as a percent of Y, percent change, and increase/decrease by a percent.

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🧮 Ratio & Proportion Calculator

Simplify a ratio, solve a proportion for a missing value, or split a total according to a given ratio.

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🧮 Fraction ↔ Decimal ↔ Percent Converter

Convert between a fraction, decimal, and percent, all kept in sync live, including repeating decimals.

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🧮 Random Number / List Generator

Generate unbiased random integers or decimals in a range, or randomly pick/shuffle items from a pasted list.

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🧮 Dice Roller

Roll standard dice or type dice notation like "3d6+2" to see every die result plus the total.

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🧮 BMI Calculator

Calculate BMI from metric or imperial measurements and see the WHO weight category range — a general estimate, not medical advice.

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🧮 Body Fat Estimate Calculator

Estimate body fat percentage using the US Navy circumference method — a general estimate, not medical advice.

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🧮 Calorie Burn by Activity Calculator

Estimate calories burned for over 20 common activities using standard MET values — a general estimate, not medical advice.

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🧮 Pregnancy Due Date Calculator

Estimate a due date and current gestational age from the last menstrual period using Naegele's rule — a general estimate, not medical advice.

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🧮 GPA / CGPA Calculator

Calculate weighted GPA from courses and grades, with an option to blend in a prior cumulative GPA.

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🧮 Grade Curve Calculator

Apply a flat-addition, square-root, or linear-rescale curve to a list of scores and see before/after stats.

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🧮 Tip & Bill Split Calculator

Calculate tip amount and split a bill evenly or proportionally by each person's order subtotal.

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🧮 Heart Rate Zone Calculator

Calculate max heart rate and the 5 standard training zones from age — a general estimate, not medical advice.

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🧮 Water Intake Calculator

Estimate daily water intake from body weight, activity level, and climate — a general estimate, not medical advice.

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