# How2.me – LLMs.txt # AI-readable index of all tools and calculators on How2.me # Format: https://llmstxt.org/ # Last updated: 2026-03-05 # Contact: hello@how2.me > How2.me is a free online tool platform offering 200+ calculators, text utilities, > PDF tools, and generators. No signup, no app, no cost. Tools cover finance, health, > math, date/time, home improvement, electronics, automotive, and everyday utilities. > Primary audience: global users with strong Singapore focus. ## Financial Calculators - [Mortgage Calculator](https://how2.me/mortgage-calculator/): Monthly payment, total interest, and amortization schedule for home loans. - [Loan Calculator](https://how2.me/loan-calculator/): Monthly payments and amortization for any loan. - [Auto Loan Calculator](https://how2.me/auto-loan-calculator/): Car payment estimator with down payment and trade-in. - [Compound Interest Calculator](https://how2.me/compound-interest-calculator/): Watch money grow with compounding over time. - [Simple Interest Calculator](https://how2.me/simple-interest-calculator/): I = PRT formula calculator. - [APR Calculator](https://how2.me/apr-calculator/): True annual percentage rate including fees. - [Savings Calculator](https://how2.me/savings-calculator/): Project savings growth with monthly contributions. - [Investment Calculator](https://how2.me/investment-calculator/): Forecast portfolio growth over time. - [Retirement Calculator](https://how2.me/retirement-calculator/): Plan retirement nest egg with draw-down projection. - [401(k) Calculator](https://how2.me/401k-calculator/): 401(k) balance forecast with employer match. - [Roth IRA Calculator](https://how2.me/roth-ira-calculator/): Tax-free Roth IRA growth projector. - [Income Tax Calculator](https://how2.me/income-tax-calculator/): US federal income tax estimator. - [Sales Tax Calculator](https://how2.me/sales-tax-calculator/): Add or remove sales tax for any US state. - [VAT Calculator](https://how2.me/vat-calculator/): Add or extract VAT for UK, EU, SG. - [Salary Calculator](https://how2.me/salary-calculator/): Convert hourly to annual salary and vice versa. - [Take-Home Pay Calculator](https://how2.me/take-home-paycheck-calculator/): Net paycheck after all US deductions. - [FIRE Calculator](https://how2.me/fire-calculator/): Financial Independence Retire Early number and date. - [Budget Calculator](https://how2.me/budget-calculator/): Monthly budget planner. - [Debt-to-Income Ratio Calculator](https://how2.me/debt-to-income-ratio-calculator/): DTI ratio for loan qualification. - [Finance Calculator](https://how2.me/finance-calculator/): Time value of money: PV, FV, rate, payment. - [Present Value Calculator](https://how2.me/present-value-calculator/): Discount future cash flows to today. - [Future Value Calculator](https://how2.me/future-value-calculator/): Project today's investment into the future. ## Health & Fitness Calculators - [BMI Calculator](https://how2.me/bmi-calculator/): Body Mass Index with WHO weight categories. - [Calorie Calculator](https://how2.me/calorie-calculator/): Daily calorie needs using Mifflin-St Jeor. - [BMR Calculator](https://how2.me/bmr-calculator/): Basal Metabolic Rate at rest. - [TDEE Calculator](https://how2.me/tdee-calculator/): Total Daily Energy Expenditure with activity levels. - [Body Fat Calculator](https://how2.me/body-fat-calculator/): Body fat percentage via US Navy method. - [Ideal Weight Calculator](https://how2.me/ideal-weight-calculator/): Ideal body weight using 4 formulas. - [Target Heart Rate Calculator](https://how2.me/target-heart-rate-calculator/): Heart rate training zones via Karvonen. - [Water Intake Calculator](https://how2.me/water-intake-calculator/): Daily hydration target. - [One Rep Max Calculator](https://how2.me/one-rep-max-calculator/): Estimate 1RM for weightlifting. - [Pace Calculator](https://how2.me/pace-calculator/): Running pace and race finish time. - [Waist-to-Hip Ratio Calculator](https://how2.me/waist-to-hip-ratio-calculator/): Cardiovascular risk via WHR. - [Lean Body Mass Calculator](https://how2.me/lean-body-mass-calculator/): LBM and FFMI calculation. - [Asian BMI Calculator](https://how2.me/asian-bmi-calculator/): BMI with WHO Asian-specific thresholds. - [Blood Pressure Calculator](https://how2.me/blood-pressure-calculator/): Blood pressure classification per AHA/ACC 2017. - [BAC Calculator](https://how2.me/bac-calculator/): Blood alcohol content via Widmark formula. - [Sleep Calculator](https://how2.me/sleep-calculator/): Optimal bedtime based on 90-min sleep cycles. - [Height Calculator](https://how2.me/height-calculator/): Height conversion and child height predictor. ## Women's Health - [Ovulation Calculator](https://how2.me/ovulation-calculator/): Fertile window prediction with 3-cycle forecast. - [Period Calculator](https://how2.me/period-calculator/): Next period date and 6-month cycle tracking. - [Due Date Calculator](https://how2.me/due-date-calculator/): Pregnancy due date from LMP or conception. ## Nutrition - [Macro Calculator](https://how2.me/macro-calculator/): Protein, carbs, and fat targets for any goal. - [Calories Burned Calculator](https://how2.me/calories-burned-calculator/): Calories burned in 25+ activities. ## Math & Science - [Basic Calculator](https://how2.me/basic-calculator/): Fast everyday arithmetic with history. - [Scientific Calculator](https://how2.me/scientific-calculator/): Trig, log, powers, factorial, inverse. - [Percentage Calculator](https://how2.me/percentage-calculator/): 3-mode percentage tool. - [Fraction Calculator](https://how2.me/fraction-calculator/): Add, subtract, multiply, divide fractions. - [Ratio Calculator](https://how2.me/ratio-calculator/): Simplify, compare, and scale ratios. - [Quadratic Formula Calculator](https://how2.me/quadratic-formula-calculator/): Solve ax²+bx+c=0. - [Roman Numeral Converter](https://how2.me/roman-numeral-converter/): Arabic ↔ Roman numeral conversion. - [Molarity Calculator](https://how2.me/molarity-calculator/): Concentration, moles, mass, and dilution. - [Molecular Weight Calculator](https://how2.me/molecular-weight-calculator/): MW from any chemical formula. - [Area Calculator](https://how2.me/area-calculator/): Area for 11 geometric shapes. - [Volume Calculator](https://how2.me/volume-calculator/): Volume for 10 3D shapes. - [Triangle Calculator](https://how2.me/triangle-calculator/): Solve any triangle (SSS/SAS/ASA/AAS). - [Pythagorean Theorem Calculator](https://how2.me/pythagorean-theorem-calculator/): a²+b²=c². - [Mean Median Mode Calculator](https://how2.me/mean-median-mode-calculator/): Descriptive statistics. - [Z-Score Calculator](https://how2.me/z-score-calculator/): Z-score and percentile from normal distribution. - [GDP Calculator](https://how2.me/gdp-calculator/): GDP, growth rate, and per capita analysis. ## Date & Time - [Date Calculator](https://how2.me/date-calculator/): Date differences, add/subtract days, workdays. - [Age Calculator](https://how2.me/age-calculator/): Exact age in years, months, days. - [Time Calculator](https://how2.me/time-calculator/): Time differences and add/subtract time. - [Hours Calculator](https://how2.me/hours-calculator/): Work hours with break deductions and pay. - [Time Duration Calculator](https://how2.me/time-duration-calculator/): Duration between two times. - [Day Counter](https://how2.me/day-counter/): Days until or since any date. - [Day of the Week Calculator](https://how2.me/day-of-the-week-calculator/): What day was/is any date. - [Sleep Calculator](https://how2.me/sleep-calculator/): Best bedtime by sleep cycle. - [Time Zone Calculator](https://how2.me/time-zone-calculator/): World time zone conversions. - [Time Card Calculator](https://how2.me/time-card-calculator/): Weekly work hours and payroll. ## Everyday Tools - [Tip Calculator](https://how2.me/tip-calculator/): Tip amount and bill splitting. - [Conversion Calculator](https://how2.me/conversion-calculator/): 11-category unit converter. - [Shoe Size Conversion](https://how2.me/shoe-size-conversion/): US, UK, EU, CM shoe size chart. - [GPA Calculator](https://how2.me/gpa-calculator/): GPA on 4.0 and 5.0 scales. - [Grade Calculator](https://how2.me/grade-calculator/): Weighted grades and final exam target. - [Weight Calculator](https://how2.me/weight-calculator/): Weight unit conversion with planetary comparison. - [Mass Calculator](https://how2.me/mass-calculator/): Mass conversion and density×volume. - [Density Calculator](https://how2.me/density-calculator/): Solve density, mass, or volume. - [Speed Calculator](https://how2.me/speed-calculator/): Speed, distance, time solver. - [Dice Roller](https://how2.me/dice-roller/): D4–D100 dice roller with history. ## Home & Construction - [Concrete Calculator](https://how2.me/concrete-calculator/): Bags and volume for any concrete job. - [Square Footage Calculator](https://how2.me/square-footage-calculator/): Area for multiple room shapes. - [Roofing Calculator](https://how2.me/roofing-calculator/): Shingles, squares, and roofing cost. - [Tile Calculator](https://how2.me/tile-calculator/): Tiles needed with waste factor. - [Mulch Calculator](https://how2.me/mulch-calculator/): Mulch volume in cubic yards and bags. - [Gravel Calculator](https://how2.me/gravel-calculator/): Gravel in tons, cubic yards, cubic metres. - [Stair Calculator](https://how2.me/stair-calculator/): Steps, rise, run, stringer, IRC compliance. - [BTU Calculator](https://how2.me/btu-calculator/): Heating/cooling BTU estimator. ## Electronics & Tech - [Ohm's Law Calculator](https://how2.me/ohms-law-calculator/): V, I, R, P from any two values. - [Voltage Drop Calculator](https://how2.me/voltage-drop-calculator/): Wire voltage drop with NEC check. - [Electricity Cost Calculator](https://how2.me/electricity-calculator/): Appliance electricity cost. - [Resistor Calculator](https://how2.me/resistor-calculator/): Color code decoder + series/parallel. - [Bandwidth Calculator](https://how2.me/bandwidth-calculator/): Download time and speed unit converter. - [IP Subnet Calculator](https://how2.me/ip-subnet-calculator/): IPv4 CIDR subnetting. ## Automotive - [Horsepower Calculator](https://how2.me/horsepower-calculator/): HP from torque×RPM or 1/4-mile ET. - [Fuel Cost Calculator](https://how2.me/fuel-cost-calculator/): Trip fuel cost estimator. - [Mileage Calculator](https://how2.me/mileage-calculator/): MPG and trip cost. - [Gas Mileage Calculator](https://how2.me/gas-mileage-calculator/): Fuel economy and annual cost tracking. - [Tire Size Calculator](https://how2.me/tire-size-calculator/): Tire dimensions and size comparison. ## Fun & Lifestyle - [Love Calculator](https://how2.me/love-calculator/): Fun name compatibility scorer. - [Wind Chill Calculator](https://how2.me/wind-chill-calculator/): Feels-like temperature with frost risk. - [Dew Point Calculator](https://how2.me/dew-point-calculator/): Dew point, humidity, wet-bulb. - [Golf Handicap Calculator](https://how2.me/golf-handicap-calculator/): WHS Handicap Index from recent rounds. ## Text Tools - [Word Counter](https://how2.me/word-counter/): Words, characters, sentences, reading time. - [Case Converter](https://how2.me/text-case-converter/): UPPER, lower, Title, camelCase, snake_case. - [Remove Duplicate Lines](https://how2.me/remove-duplicate-lines/): Deduplicate line lists instantly. - [Add Prefix/Suffix](https://how2.me/add-prefix-suffix/): Batch-add text to every line. - [Find & Replace](https://how2.me/find-replace/): Text find and replace tool. ## Generators - [Password Generator](https://how2.me/password-generator/): Strong random password creator. - [QR Code Generator](https://how2.me/qr-code-generator/): Free QR codes for URLs, text, email. - [Lorem Ipsum Generator](https://how2.me/lorem-ipsum/): Placeholder text by word, sentence, or paragraph. ## Optional - [About How2.me](https://how2.me/about/): Learn about the platform. - [Privacy Policy](https://how2.me/privacy-policy/): Our data and privacy practices. - [Contact](https://how2.me/contact/): Get in touch with the How2.me team.