200 tools.
One trip.

Slope Calculator

Find the slope between two points — plus equation, angle, distance, and midpoint

Volume of a Cube Calculator

Volume from one side length — plus surface area, face & space diagonals

Volume of a Sphere Calculator

Sphere volume from radius or diameter — plus surface area and great-circle circumference

Volume of a Cone Calculator

Cone volume from radius and height — plus slant height and surface area

Rectangle Area Calculator

Area, perimeter, and diagonal from length and width

Factorial Calculator

Compute n! exactly for n up to 170, scientific notation up to n = 1000

Mg to Ml Converter

Convert milligrams to millilitres (and back) — for water, oils, alcohol, and medications

Square Footage Calculator

Add up rooms in ft, in, m, or cm — totals shown in sq ft and m²

Weeks Left in the Year Calculator

Auto-counts weeks remaining in the current year — plus days, day-of-year, and percent done

Sales Tax Calculator

Add tax to a price or extract tax from a total — US state presets included

Annual Income Calculator

Convert any pay rate (hourly, weekly, monthly) to annual — and back to every other interval

Permutation Calculator

P(n, k) = n! / (n−k)! — arrangements where order matters

Combination Calculator

C(n, k) = n! / (k! × (n−k)!) — selections where order does not matter

Logarithm Calculator

ln (natural), log₁₀, log₂, or any custom base — answers 'what power gives me this number?'

Volume Calculator

Volume of cube, rectangular box, cylinder, sphere, cone, or pyramid — one tool

Surface Area Calculator

Surface area of cube, box, cylinder, sphere, cone, or pyramid — total and lateral

Standard Deviation Calculator

Sample and population SD plus mean, median, variance, min/max — paste any list of numbers

Tablespoon to Grams Converter

Convert tbsp to grams (and back) for flour, sugar, butter, salt, honey, oil, and 15+ kitchen staples

Period Calculator

Predict your next 4 periods plus ovulation and fertile window from your last period date and cycle length

Ovulation Calculator

Find your ovulation date, fertile window, and peak conception days for the next 3 cycles

Due Date Calculator

Pregnancy due date from last period, conception, or IVF transfer — plus current week and trimester

Dog Age Calculator

Convert dog years to human years using the modern AVMA formula — size-adjusted, not the '× 7' myth

Millionaire Calculator

How long until you hit $1M (or any target) given starting balance, monthly contributions, and rate of return

Height Predictor

Predict a child's adult height from parental heights using the mid-parental (Tanner) method

Long Division Calculator

Divide step-by-step with the algorithm you learned in school — quotient, remainder, and every intermediate step

Minecraft Circle Generator

Generate pixel circles for Minecraft towers, walls, and floors — diameters 1 to 64

Moon Phase Calculator

Find the moon phase for any date — illumination percent, days into the cycle, and next new/full moon

Sunrise/Sunset Calculator

Sunrise and sunset times for any date and location — uses the NOAA algorithm

Binary Decoder

Decode binary code (8-bit ASCII bytes) into readable text — accepts spaces, commas, or no separators

Concrete Calculator

Concrete needed for slabs, footings, columns, and stairs — in cubic yards, cubic metres, and bag count

Word Counter

Count words, characters & reading time

Character Counter

Count characters with and without spaces

Paraphrasing Tool

Rewrite text in your own words

Text Summarizer

Summarize long text into key points

AI Bio Generator

Generate professional bios for LinkedIn

Cover Letter Generator

Generate tailored cover letters fast

Hashtag Generator

Generate trending hashtags for social media

Caption Generator

Generate engaging captions for Instagram

AI Poem Writer

Write poems on any topic or style

Outline Generator

Generate an AI-style outline from a topic

Thank You Note Generator

Generate heartfelt thank you notes

Email Subject Generator

Generate high-open-rate email subject lines

JSON Formatter

Format and validate JSON data

Base64 Encoder/Decoder

Encode and decode Base64 strings

Regex Tester

Test and debug regular expressions

JSON to CSV

Convert JSON arrays to CSV format

CSV to JSON

Convert CSV to JSON format

URL Encoder/Decoder

Encode and decode URLs

HTML Encoder/Decoder

Encode and decode HTML entities

SHA-256 Generator

Generate SHA-256 cryptographic hash

MD5 Hash Generator

Generate MD5 hashes from any text

UUID Generator

Generate random UUID v4 identifiers

Curl Builder

Build cURL commands from a URL

Binary Decoder

Decode binary code (8-bit ASCII bytes) into readable text — accepts spaces, commas, or no separators

Percentage Calculator

Calculate percentages, discounts & more

BMI Calculator

Calculate your Body Mass Index

Tip Calculator

Calculate tips and split bills

Loan Calculator

Calculate monthly payments & total interest

Compound Interest Calc

See how your money grows over time

Average Calculator

Calculate mean, median, mode & range

Standard Deviation Calculator

Sample and population SD plus mean, median, variance, min/max — paste any list of numbers

Factorial Calculator

Compute n! exactly for n up to 170, scientific notation up to n = 1000

Combination Calculator

C(n, k) = n! / (k! × (n−k)!) — selections where order does not matter

Permutation Calculator

P(n, k) = n! / (n−k)! — arrangements where order matters

Logarithm Calculator

ln (natural), log₁₀, log₂, or any custom base — answers 'what power gives me this number?'

Long Division Calculator

Divide step-by-step with the algorithm you learned in school — quotient, remainder, and every intermediate step