A collection of 87+ free calculator tools for everyday life.
🇯🇵 日本語版
Calculate BMI from height and weight. Check obesity level and ideal weight.
Estimate body fat percentage from height, weight, age, and gender.
Calculate calories burned during exercise and daily activities.
Convert dog/cat age to human years. Size-specific conversion.
Calculate pregnancy weeks and due date from last menstrual period.
Calculate optimal sleep/wake times based on 90-minute sleep cycles.
Calculate basal metabolic rate and daily calorie expenditure.
Calculate alcohol decomposition time and estimated sober time.
Calculate ideal weight and daily calorie deficit for your goal.
Calculate calories and nutrients for common foods.
Instantly convert between tax-inclusive and tax-exclusive prices.
Easily split bills for dining. Handles remainder.
Calculate monthly/yearly electricity costs from wattage.
Convert length, weight, temperature, and area units.
Calculate discounted price. Supports double discounts.
Calculate area for various shapes with unit conversion.
Calculate speed, distance, or time. Marathon pace included.
Generate random numbers in a specified range. Lottery mode included.
Convert between 10 major currencies.
Simulate monthly payments and total cost for mortgages and car loans.
Calculate take-home pay from gross salary with tax breakdown.
Simulate asset growth with compound interest and regular contributions.
Estimate maximum deduction for hometown tax donations.
Simulate housing loan tax deduction amounts.
Calculate daily/monthly/yearly income from hourly rate.
Calculate points earned and effective discount from reward rate.
Estimate future pension amounts from salary and enrollment period.
Compare up to 3 loan conditions side by side.
Calculate the number of days between two dates.
Calculate age from birthday. Shows days lived and next birthday countdown.
Add/subtract times and calculate time differences.
Convert between Japanese era (Reiwa, Heisei, etc.) and Western calendar.
Convert time between major world timezones.
Real-time countdown to your target date and time.
Precision stopwatch with lap time recording.
Browse years with era, age, and zodiac information.
Convert between Unix timestamps and human-readable dates.
Count characters, words, lines, and bytes in real-time.
Calculate mean, median, standard deviation, and more.
Calculate factorials, permutations, and combinations.
Compare two texts with color-highlighted differences.
Calculate percentages, ratios, and percentage changes.
Calculate tip amount and split the bill per person.
Calculate weighted GPA from grades and credits.
Display a date in multiple formats (ISO 8601, RFC 2822, etc.).
Calculate overtime pay based on Japanese labor law rates.
Calculate recommended daily water intake by weight and activity.
Calculate max heart rate and 5 training zones by age.
Convert shoe sizes between Japan, US, UK, and EU.
Convert cooking measurements (tbsp, tsp, cup, mL, g) by ingredient.
Simulate months to reach savings goal with interest.
Calculate fuel cost from distance and efficiency, or distance from budget.
Estimate moving costs by distance, household size, and season.
Calculate recommended rent range from your income.
Reference table for A/B series and common paper sizes.
Calculate and convert aspect ratios with common presets.
Predict next period, ovulation, and fertile window.
Check blood type compatibility and personality traits (entertainment).
Find your Western zodiac sign and Chinese zodiac from your birthdate.
Recommended gift amounts for weddings and funerals by relationship.
Calculate school entry and graduation years from birthdate (Japanese system).
Calculate annual car tax by engine displacement (Japanese tax rates).
Estimate retirement pay and tax from salary, years of service, and type.
Calculate next car inspection date and upcoming schedule.
Calculate paint and wallpaper needed from room dimensions.
Estimate WBGT heat index from temperature and humidity.
Calculate wind chill temperature from air temp and wind speed.
Generate secure passwords with strength meter.
Generate SHA-1/SHA-256/SHA-512 hashes from text.
Generate v4 UUIDs with bulk generation and validation.
Convert between binary, octal, decimal, and hexadecimal.
Convert between HEX, RGB, and HSL color formats.
Format, minify, and validate JSON.
Base64, URL, and HTML entity encoding/decoding.
Test regex patterns in real-time with match highlighting.
Calculate network address, broadcast, and host range from CIDR.
Parse cron expressions with next execution times.
Calculate file permissions with intuitive checkbox UI.
Decode JWT token header and payload. Check expiration.
Bidirectional CSV and JSON conversion.
Auto-format SQL queries for readability.
Convert between B/KB/MB/GB/TB/PB.
Reference for HTTP status codes and their meanings.
Real-time markdown preview with HTML copy.
Generate linear/radial CSS gradients visually.
Generate QR codes from text or URLs instantly.
Generate dummy text by paragraphs, sentences, or words.