Math

Number Base Converter

Convert numbers between binary, octal, decimal, and hexadecimal bases instantly.

Date & Time

Business Days Calculator

Count the number of working days between two dates, excluding weekends and optional public

Finance

One Rep Max Calculator

Estimate your one-rep max (1RM) for any lift using weight lifted and number of reps perfor

Everyday

Roman Numeral Converter

Convert between Roman numerals and Arabic numbers instantly. Supports values from 1 to 399

Date & Time

Working Days Calculator

Calculate the number of working days between two dates, excluding weekends and optional pu

Everyday

Data Storage Converter

Convert between bytes, KB, MB, GB, TB and more. Essential for developers and IT profession

Statistics

Mean Median Mode Calculator

Calculate mean, median, mode, range and standard deviation for a set of numbers.

Everyday

Binary to Decimal Converter

Convert between binary, decimal, hexadecimal, and octal number systems instantly.

Math

GCD and LCM Calculator

Calculate the Greatest Common Divisor (GCD) and Least Common Multiple (LCM) of two or more

Date & Time

Add Days to Date Calculator

Add or subtract any number of days from a date to find a future or past date instantly.

Math

Prime Number Checker

Check if a number is prime and find all prime factors of any number instantly.

Date & Time

Calendar Week Number Calculator

Find the ISO week number of any date and see the start and end dates of that week.

Everyday

Number to Words Converter

Convert any number up to one trillion into words in English. Useful for cheques, invoices,

Chemistry

Redox Reaction Balancer Guide

Calculate the oxidation state of elements in common chemical compounds and ions.

Everyday

IP Subnet Calculator

Calculate network address, broadcast address, host range, and number of hosts for any IPv4

Everyday

Hex to Binary Converter

Convert hexadecimal numbers to binary, decimal and octal. Also convert binary or decimal t

Physics

Wavelength to Energy Calculator

Calculate the energy of a photon from its wavelength or frequency using E=hf and E=hc/λ.

Everyday

Permutation and Combination Calculator

Calculate nPr (permutations) and nCr (combinations) for any values of n and r.

Everyday

Significant Figures Calculator

Round any number to a specified number of significant figures and identify sig figs in any

Everyday

Binary Calculator

Perform addition, subtraction, multiplication and division on binary numbers with step-by-

Construction

Fence Calculator

Calculate the number of fence panels, posts and rails needed for any yard or property boun

Engineering

Bandwidth Calculator

Calculate network bandwidth, data transfer time and internet speed requirements for files

Engineering

Pipe Flow Rate Calculator

Calculate the volumetric flow rate through a pipe using pipe diameter and fluid velocity.

Construction

Tile Calculator

Calculate the number of tiles needed for any floor or wall area including waste factor.

Everyday

Tip Split Calculator

Calculate tip amount and split the total bill among any number of people with custom tip p

Everyday

Numerology Calculator

Calculate your Life Path Number, Expression Number and Soul Urge Number based on your name

Everyday

Electricity Bill Splitter

Split your electricity bill fairly among roommates or household members based on usage or

Construction

Stair Calculator

Calculate stair dimensions including number of steps, riser height, tread depth and total