Simple tools for everyday calculations
Use fast calculators, converters and text utilities organized by category. No sign-up required.
Text Tools
Text, formatting and developer-friendly utilities for cleaning, transforming, encoding and validating text data.
Base64 Encoder & Decoder
Encode UTF-8 text to Base64 or decode Base64 back to text.
Open tool → Text ToolsCase Converter
Convert text to uppercase, lowercase, title case or sentence case.
Open tool → Text ToolsCharacter Counter
Count characters with and without spaces.
Open tool → Text ToolsCSV to JSON Converter
Convert simple delimited tabular text into a JSON array of objects.
Open tool → Text ToolsFind and Replace Tool
Find plain text and replace every matching occurrence in a larger block of text.
Open tool → Text ToolsHTML Entity Encoder & Decoder
Encode common HTML-sensitive characters or decode HTML entities to readable text.
Open tool → Text ToolsJSON Formatter & Validator
Validate JSON and format valid JSON with readable indentation.
Open tool → Text ToolsReading Time Calculator
Estimate reading time from word count and reading speed.
Open tool →Math Tools
Everyday and study-focused math calculators for arithmetic, algebra, geometry, combinatorics and number operations.
Absolute Value Calculator
Find the non-negative absolute value of a number.
Open tool → Math ToolsAverage Calculator
Find the arithmetic mean of a list of numbers.
Open tool → Math ToolsCircle Calculator
Calculate circle diameter, circumference and area from radius.
Open tool → Math ToolsExponent Calculator
Raise a base number to a chosen exponent.
Open tool → Math ToolsFactorial Calculator
Calculate n! for a non-negative whole number.
Open tool → Math ToolsFraction to Percent Calculator
Convert a fraction into a percentage.
Open tool → Math ToolsGCD & LCM Calculator
Find the greatest common divisor (GCD) and least common multiple (LCM) of two positive whole numbers.
Open tool → Math ToolsLogarithm Calculator
Calculate a logarithm using any valid positive base except 1.
Open tool →Finance & Shopping
Shopping and money estimation tools for prices, tax, margins, growth, commissions, savings and simple payment calculations.
Break-Even Calculator
Estimate break-even units from fixed cost, unit price and variable cost per unit.
Open tool → Finance & ShoppingCAGR Calculator
Calculate compound annual growth rate between a beginning value and ending value.
Open tool → Finance & ShoppingCommission Calculator
Calculate commission amount from sales value and commission rate.
Open tool → Finance & ShoppingCompound Interest Calculator
Estimate compound growth from a starting amount, annual rate, time period and compounding frequency.
Open tool → Finance & ShoppingDebt-to-Income Ratio Calculator
Calculate a simple monthly debt-to-gross-income percentage.
Open tool → Finance & ShoppingDiscount Calculator
Calculate sale price and amount saved.
Open tool → Finance & ShoppingFuel Cost Calculator
Estimate trip fuel use and fuel cost from distance, efficiency and fuel price.
Open tool → Finance & ShoppingLoan EMI Calculator
Estimate a fixed monthly payment for a standard amortizing loan.
Open tool →Converters
Unit converters for physical measurements, engineering values, cooking, fuel economy and digital transfer rates.
Acceleration Converter
Convert acceleration between m/s², ft/s², standard gravity and Gal.
Open tool → ConvertersAngle Converter
Convert angles between degrees, radians, gradians and turns.
Open tool → ConvertersArea Converter
Convert square meters, square feet, acres, hectares and other common area units.
Open tool → ConvertersCooking Measurement Converter
Convert common liquid cooking volumes including mL, liters, teaspoons, tablespoons, cups and US fluid units.
Open tool → ConvertersData Storage Converter
Convert bytes, KB, MB, GB and TB using decimal storage units.
Open tool → ConvertersData Transfer Rate Converter
Convert network and file-transfer rates between bits per second and bytes per second units.
Open tool → ConvertersDensity Converter
Convert density between kg/m³, g/cm³, lb/ft³ and lb/in³.
Open tool → ConvertersEnergy Converter
Convert joules, kilojoules, calories, kilocalories, watt-hours and kilowatt-hours.
Open tool →Date & Time
Date and time calculators for ages, date gaps, business days, week numbers, timestamps and fixed UTC-offset conversions.
Add or Subtract Days Calculator
Add a positive or negative number of calendar days to a selected date.
Open tool → Date & TimeAge Calculator
Calculate age in completed years, months and days between two dates.
Open tool → Date & TimeBusiness Days Calculator
Count Monday-through-Friday calendar days between two dates, including both endpoints.
Open tool → Date & TimeDate Difference Calculator
Find the number of calendar days between two dates.
Open tool → Date & TimeDays Until Date Calculator
Calculate how many calendar days remain until a selected date, or how many days have passed since it.
Open tool → Date & TimeISO Week Number Calculator
Find the ISO-8601 week number and week-year for a calendar date.
Open tool → Date & TimeTime Duration Calculator
Find elapsed hours and minutes between two clock times.
Open tool → Date & TimeTime Zone Offset Calculator
Convert a date and clock time between two numeric UTC offsets.
Open tool →Health Tools
General health screening calculators with clear limitations and non-diagnostic guidance.
Built for quick, understandable results
SmartCheu keeps the tool first and explains the method underneath.
No sign-up required
Open a calculator or utility, enter the values you need and get the result without creating an account.
Clear formulas and examples
Each tool page explains the calculation or conversion basis so you can understand and verify the result.
Category-wise navigation
Related tools are grouped together and internally linked, making it easier to find the next calculator you need.