Free tools for time, dates, text, and everyday math

Life in Weeks

Your whole life as a grid of weeks: lived, remaining, and the milestones in between.

Age Calculator

Exact age in years, months, and days, plus your age on any date and the next birthday countdown.

Days Between Dates

Days, weeks, months, and weekdays between any two dates.

Date Calculator

Add or subtract days, weeks, months, and years from a date.

Countdown to a Date

Live countdown to any date and time, with a shareable link.

Online Timer

Simple countdown timer with an alarm, presets, and a full-screen view.

Stopwatch

Stopwatch with lap times, split averages, and keyboard controls.

Pomodoro Timer

Focus and break intervals with session tracking and sound.

World Clock

Current time in cities around the world, side by side.

Time Zone Converter

Convert a time across several time zones at once, DST-aware.

Meeting Time Planner

Find the overlap in working hours across time zones.

UTC Time Converter

Convert between your local time and UTC / GMT.

New York to London Time

Convert New York (ET) to London (GMT/BST) and back.

Los Angeles to Tokyo Time

Convert Los Angeles (PT) to Tokyo (JST) and back.

Chicago to Sydney Time

Convert Chicago (CT) to Sydney (AEST/AEDT) and back.

Business Days Calculator

Working days between two dates, with US federal holidays excluded.

Add or Subtract Business Days

The date that is N business days before or after a start date.

Workday Count

How many working days are in a month, quarter, or year.

Deadline Calculator

Due dates from a start date in calendar or business days.

Day of the Week

What day of the week any past or future date falls on.

Week Number

ISO week number for any date, and the current week.

Day of the Year

Day number of the year, days remaining, and year progress.

Unix Timestamp Converter

Epoch seconds or milliseconds to a human date and back, live.

Time Duration Calculator

Add and subtract hours and minutes, or the time between two clock times.

Hours Worked Calculator

Time card: clock in, clock out, breaks, weekly total, and decimal hours.

Sleep Calculator

Bedtimes and wake-up times aligned to 90-minute sleep cycles.

Leap Year Checker

Is it a leap year? List every leap year in a range.

Moon Phase

The moon phase for any date and the next full and new moons.

Sunrise & Sunset

Sunrise, sunset, solar noon, and day length for any location and date.

Birthday Calculator

Day you were born, days until your next birthday, and milestone birthdays.

Cron Expression Generator

Build a cron schedule, read it in plain English, and see the next runs.

Printable Calendar

Clean monthly and yearly calendars for any year, ready to print.

Zodiac Sign

Western and Chinese zodiac sign, birthstone, and generation from a birth date.

Due Date Calculator

Estimated due date, current week, and trimester from your last period or conception.

Dog Age in Human Years

Convert dog and cat years to human years with the modern research formula.

Year Progress

How much of the year, month, week, and day has already passed, live.

Word Counter

Words, characters, sentences, paragraphs, reading time, and top keywords.

Case Converter

UPPER, lower, Title, Sentence, camelCase, snake_case, and kebab-case.

Text Diff

Compare two texts and highlight every added and removed line or word.

Lorem Ipsum Generator

Placeholder paragraphs, sentences, or words, with an optional classic opening.

Slug Generator

Turn any title into a clean, URL-safe slug.

Line Tools

Sort, deduplicate, reverse, shuffle, trim, and number lines of text.

Find and Replace

Replace text with plain or regex matching, case and whole-word options.

Markdown Preview

Write markdown on the left, see the rendered page on the right.

Text Cleaner

Strip HTML, collapse whitespace, fix smart quotes, and remove line breaks.

JSON Formatter

Pretty-print, minify, and validate JSON with the exact error position.

Base64 Encode / Decode

Text and files to Base64 and back, with URL-safe output.

URL Encode / Decode

Percent-encode strings or decode them, component or full URL.

Regex Tester

Live matches, capture groups, and replacements with a syntax cheat sheet.

Hash Generator

MD5, SHA-1, SHA-256, SHA-384, and SHA-512 of text or a file.

UUID Generator

Random v4 and time-ordered v7 UUIDs, one or in bulk.

JWT Decoder

Decode a JSON Web Token's header and payload and check its expiry.

HTML Entity Encoder

Escape and unescape HTML entities and special characters.

Color Converter

HEX, RGB, HSL, HSV, and CMYK with tints, shades, and contrast ratios.

Password Generator

Strong random passwords and passphrases with an entropy estimate.

Number Base Converter

Binary, octal, decimal, hex, and any base from 2 to 36.

QR Code Generator

QR codes for links, text, and Wi-Fi, downloadable as PNG.

Chmod Calculator

Unix file permissions between checkboxes, octal, and symbolic notation.

Unit Converter

Length, weight, temperature, volume, area, speed, data, pressure, and energy.

Temperature Converter

Celsius, Fahrenheit, and Kelvin with a quick reference table.

Cooking Converter

Cups, tablespoons, milliliters, ounces, and grams for common ingredients.

Percentage Calculator

Percent of a number, percent change, and what percent one number is of another.

Roman Numeral Converter

Numbers to Roman numerals and back, with a year chart.

Number to Words

Spell out any number in English, including check-writing format.

Fraction Calculator

Add, subtract, multiply, and divide fractions; simplify and convert decimals.

GPA Calculator

Weighted and unweighted GPA from letter grades and credit hours.

Random Number Generator

Random numbers in a range, dice, coin flips, and picking from a list.

Average Calculator

Mean, median, mode, range, and standard deviation of a list of numbers.

Ratio Calculator

Simplify, scale, and solve ratios, including screen aspect ratios.

BMI Calculator

Body mass index in metric or imperial, with the healthy range for your height.

Calorie Calculator

BMR and daily calorie needs (TDEE) with targets for losing or gaining.

Ideal Weight

Ideal body weight by the Devine, Robinson, Miller, and Hamwi formulas.

Body Fat Calculator

Body fat percentage from tape measurements using the US Navy method.

Running Pace Calculator

Pace, time, or distance from the other two, with race-time predictions and splits.

Paint Calculator

Gallons of paint for walls and ceilings, minus doors and windows, by coats.

Deck Paint & Stain

Stain or paint needed for deck boards, railings, and stairs.

Exterior Paint Calculator

Paint for siding, trim, and gables by house dimensions.

Concrete Calculator

Cubic yards and bags of concrete for slabs, footings, columns, and steps.

Driveway Concrete

Concrete volume and bag count for a driveway slab.

Patio Concrete

Concrete for a patio slab, including waste allowance.

Flooring Calculator

Square footage, boxes, and waste for any flooring material.

Tile Calculator

Number of tiles and boxes for a floor or wall, grout gaps included.

Vinyl Flooring Calculator

Planks or sheet vinyl needed for a room, with waste factor.

Basement Flooring

Material for a basement floor with irregular rooms and stairs.

Square Footage Calculator

Area of rectangles, circles, triangles, and L-shaped rooms.

Mulch Calculator

Cubic yards and bags of mulch for beds at any depth.

Gravel Calculator

Tons and cubic yards of gravel or stone for a path, pad, or driveway.

Wallpaper Calculator

Rolls of wallpaper for a room, allowing for pattern repeat.

CPM Calculator

Cost per thousand impressions from spend and impressions, or solve for either.

CPC Calculator

Cost per click from spend and clicks, or the clicks a budget buys.

CPA Calculator

Cost per acquisition from spend and conversions.

CPM, CPC & CPA Calculator

All three metrics from one campaign's spend, impressions, clicks, and conversions.

CTR Calculator

Click-through rate and the clicks an impression count should produce.

Conversion Rate Calculator

Conversion rate, plus the lift needed to hit a target.

ROAS Calculator

Return on ad spend as a ratio and percentage, with profit after ad costs.

Break-Even ROAS

The ROAS you need to break even given margins and costs.

CAC Calculator

Customer acquisition cost and the CAC-to-lifetime-value ratio.

Campaign Budget Calculator

Budget required for a conversion target from CPM, CTR, and conversion rate.