All Your Tools in One Place

Plan retirement savings with employer match and 2026 contribution limits.

Compare Roth vs Traditional IRA growth with 2026 phase-out limits.

Estimate monthly benefits by claiming age 62–70 with break-even analysis.

Calculate take-home pay after federal, FICA, and all 50 state taxes.

Calculate SE tax, quarterly estimates, and the deductible half for freelancers.

Calculate monthly PITI payments with PMI, taxes, and insurance.

Full month-by-month payment schedule with CSV download.

Compare Standard, Extended, and IBR plans with 2026 federal rates.

See savings grow with contributions and daily/monthly/annual compounding.

Compare Avalanche vs Snowball strategies for up to 5 debts.

Find how long to reach your savings goal or how much to save monthly.

Allocate income using the 50/30/20 rule with needs, wants, and savings breakdown.

Calculate total net worth from assets and liabilities with breakdown chart.

Calculate US purchasing power from 1913 to 2025 using historical CPI data.

12 topics from fundamentals to lead-level concepts.

16 topics covering metaprogramming, ActiveRecord, and more.

14 topics: threads, GIL, Mutex, Fibers, Ractor, deadlocks, and real-world patterns.

16 topics: data types, persistence, pub/sub, clustering, and caching patterns.

Calculate Body Mass Index and health category.

Estimate body fat percentage using the US Navy method.

Find ideal body weight range from 4 clinical formulas.

Calculate daily calorie needs for weight loss, maintenance, or gain.

Total daily energy expenditure and macro breakdown.

Calculate Basal Metabolic Rate using the Mifflin-St Jeor equation.

Calculate daily protein, carbs, and fat targets based on your goal.

Calculate daily water intake based on weight, activity, and climate.

Find your ideal bedtime and wake-up time based on 90-minute sleep cycles.

Find your due date, trimester, and key pregnancy milestones from LMP or gestational age.

Calculate exact age in years, months, and days.

Find days between dates or add/subtract time.

Stay focused with 25-minute work sessions and breaks.

Set any duration and count down with audio alarm.

Count up with lap times, accurate to the centisecond.

Convert any time between 20 major world time zones.

Current local time in 15 major cities worldwide.

Count down days until Christmas, New Year, birthdays, or any custom date.

Count working days between dates or find a date N business days away.

Find out what day of the week any date falls on — past or future.

Find the ISO week number for any date and view all 52 weeks of the year.

Check if any year is a leap year and find the next upcoming one.

Full scientific calculator with trig, logs, and memory.

Calculate weighted grades, GPA, and final exam needed.

Mean, median, mode, standard deviation, and quartiles.

Calculate percentages four ways — X% of Y, percentage change, and more.

Add, subtract, multiply, and divide fractions with step-by-step solutions.

Add or subtract time durations. Calculate the difference between two times.

Calculate area, perimeter, and volume for 11 shapes — circle, rectangle, triangle, and more.

Calculate tips and split bills among friends.

Calculate sale prices and savings instantly.

Calculate trip fuel cost and compare two vehicles.

Create QR codes for URLs, WiFi, text, and more.

Pick colors and convert between HEX, RGB, HSL.

Convert colors between HEX, RGB, HSL, and CMYK.

Create linear and radial CSS gradients visually with live preview.

Generate harmonious color palettes from any base color using color theory.

Meters, km, miles, feet, inches, yards.

Kg, pounds, ounces, grams, stones.

Celsius, Fahrenheit, Kelvin.

Sq meters, sq feet, acres, hectares.

Km/h, mph, m/s, knots.

GB, MB, TB, KB, bytes.

Liters, gallons, cups, pints, fluid ounces, cubic meters.

Convert between binary, octal, decimal, and hexadecimal.

Convert pixels to REM for responsive CSS.

Convert pixels to EM based on parent font-size.

Format, validate, and minify JSON.

Format and beautify SQL queries.

Format, indent, and validate XML documents online.

Beautify and format HTML code with proper indentation.

Format, validate, and convert YAML to JSON online.

Beautify and format CSS code for readability.

Visual CSS box-shadow builder with live preview and copy.

Visual rounded corners CSS builder with live preview.

Calculate width, height, or ratio for any aspect ratio.

Generate random UUID v4 identifiers.

MD5, SHA-1, SHA-256 hash calculation.

Generate secure random passwords.

Decode and inspect JWT header, payload, and signature.

Encode and decode Base64 strings.

Percent-encode and decode URLs.

Encode/decode HTML entities — escape < > & " instantly.

Minify CSS to reduce file size for production.

Minify JavaScript code to reduce file size for production.

Convert Unix epoch timestamps to human-readable dates.

Convert Ruby Hashes to valid JSON.

Convert images to Base64 data URI strings.

Convert text to uppercase, lowercase, title case.

Count words, characters, sentences, paragraphs.

Search and replace text patterns.

Compare two texts and highlight differences.

Test and debug regular expressions.

Write markdown with live preview.

Generate placeholder text for designs.

Clean and format messy text.

Remove duplicate lines from text.

Reverse text, words, or lines.

Generate strikethrough unicode text.

Copy special characters and symbols.

Count characters, words, and check against Twitter/SMS limits.

Add prefix or suffix to each line of text in bulk.

Generate random numbers within any range, including unique sets.

Flip a virtual coin with cryptographically secure randomness.

Roll D4, D6, D8, D10, D12, or D20 dice — up to 10 at once.

Generate random first and last names by gender and origin.

Shuffle and randomize any list of items instantly.

Generate random colors with HEX, RGB, and HSL values.