50tools
A collection of 50 fast, secure, and 100% offline-capable tools for finance, fitness, math, tech, and everyday tasks.
Finance
16Mortgage Calculator
Calculate monthly mortgage payments including principal, interest, taxes, insurance, and HOA fees.
Open Calculator →Mortgage Payoff Calculator
Calculate interest savings and how much faster you will pay off your mortgage by adding extra monthly payments.
Open Calculator →Loan Calculator
Calculate payment schedules, interest, and payoff dates for personal, student, or business loans.
Open Calculator →Auto Loan Calculator
Calculate monthly car payments, sales taxes, fees, and interest based on dealer pricing and trade-in inputs.
Open Calculator →Compound Interest Calculator
Calculate future portfolio growth by customizing interest rates, compounding frequency, and regular additions.
Open Calculator →Debt Payoff Calculator
Compare Snowball (lowest balance first) and Avalanche (highest interest first) payoff strategies to eliminate debt.
Open Calculator →Paycheck Calculator
Estimate net take-home pay based on salary inputs, pay schedules, filing status, and pre-tax deductions.
Open Calculator →Take-Home Pay Calculator
Understand your yearly, monthly, and weekly take-home income distribution after FICA and federal tax deductions.
Open Calculator →Sales Tax Calculator
Calculate sales tax amounts or reverse-calculate the pre-tax sticker price from a gross total.
Open Calculator →Retirement Savings Calculator
Project your retirement nest egg and estimate how long your savings will last during your retirement years.
Open Calculator →401(k) Growth Calculator
Calculate long-term 401(k) retirement plan value, including employer matching contributions.
Open Calculator →Crypto Profit/Loss Calculator
Calculate cryptocurrency profit, loss, fee deductions, and return on investment (ROI) percentages.
Open Calculator →Loan-to-Value (LTV) Calculator
Calculate Loan-to-Value (LTV) ratios to evaluate mortgage risk levels and PMI requirements.
Open Calculator →Rent vs. Buy Calculator
Compare the 10-year cumulative financial costs of renting an apartment vs. buying a home.
Open Calculator →Tax Bracket Calculator
Determine your marginal tax bracket and estimate your effective federal income tax rate.
Open Calculator →Freelance Hourly Rate Calculator
Calculate the hourly rate you must charge to cover target salaries, business expenses, and taxes.
Open Calculator →Health
7BMI Calculator
Calculate your Body Mass Index (BMI) and determine your weight category based on standard clinical thresholds.
Open Calculator →Calorie Calculator (TDEE)
Estimate your Total Daily Energy Expenditure (TDEE) and target calories for weight loss or gain.
Open Calculator →Body Fat Calculator
Calculate your estimated body fat percentage using the US Navy tape-measure method.
Open Calculator →Pregnancy Due Date Calculator
Calculate your estimated due date, gestational age, and trimester progress using Naegele's rule.
Open Calculator →Macro Calculator
Split your target daily calories into optimal protein, carbohydrate, and fat gram ratios.
Open Calculator →Water Intake Calculator
Calculate your daily hydration requirements based on body weight, climate, and exercise.
Open Calculator →Sleep Cycle Calculator
Calculate optimal wake-up times and bedtimes based on 90-minute sleep cycles.
Open Calculator →Math & Education
4Scientific Calculator
Evaluate complex mathematical and trigonometric expressions with an interactive scientific input interface.
Open Calculator →Fraction Calculator
Add, subtract, multiply, and divide fractions. Get step-by-step solutions with simplified results.
Open Calculator →Percentage Calculator
Calculate percentages, percentage change, and percentage differences with a multi-purpose tool set.
Open Calculator →Prime Number Checker / Factorizer
Check if a number is prime, view its divisors, prime factorization, and nearest prime numbers.
Open Calculator →Date & Time
5Date Difference Calculator
Calculate the exact duration between two dates in years, months, weeks, days, and seconds.
Open Calculator →Business Day Calculator
Calculate business days between two dates, or add/subtract business days to find a deadline.
Open Calculator →Hours (Time Card) Calculator
Calculate total worked hours from weekly check-in times with lunch break deductions.
Open Calculator →Time Zone Converter
Convert dates and times between major global time zones without external network dependencies.
Open Calculator →Age Calculator
Calculate your exact age in years, months, days, minutes, and seconds, and find your zodiac sign.
Open Calculator →Tech & Web
9Number Base Converter
Convert numbers between binary, octal, decimal, hexadecimal, and custom bases (2 to 36).
Open Calculator →Offline QR Code Generator
Generate offline QR codes for links, text, or Wi-Fi configurations without external tracker calls.
Open Calculator →Secure Password Generator
Generate strong, cryptographically secure passwords with custom entropy rules.
Open Calculator →JSON Formatter & Validator
Validate, prettify, format, and minify JSON strings with instant syntax error locations.
Open Calculator →Crypto Hash Generator
Generate MD5, SHA-1, and SHA-256 hashes from target text values completely offline.
Open Calculator →URL Encoder / Decoder
Encode or decode strings for safe query parameter passing in URLs.
Open Calculator →Unix Epoch Timestamp Converter
Convert Unix epoch timestamps to human-readable dates, and dates back to timestamps.
Open Calculator →Base64 Encoder / Decoder
Convert binary or plain text strings into safe Base64 representation, and decode it back.
Open Calculator →IP Address & Subnet Calculator
Calculate subnets, usable host ranges, wildcard masks, and binary representations for IPv4 addresses.
Open Calculator →Everyday Life
9Tip & Split Calculator
Calculate tips and split restaurant or service bills evenly among multiple people.
Open Calculator →Itemized Bill Splitter
Split items among specific diners/payers with proportional tax and tip calculations.
Open Calculator →Gas Mileage & Fuel Cost Calculator
Estimate total fuel volume and financial costs for road trips and commutes.
Open Calculator →Paint Coverage Calculator
Determine how many gallons or liters of paint are needed to cover walls and rooms.
Open Calculator →Concrete & Mulch Volume Calculator
Calculate the volume of concrete, soil, or mulch needed for slabs, walls, and circular holes.
Open Calculator →Random Number Generator
Generate single or multiple random integers within a custom range.
Open Calculator →Semester GPA Calculator
Calculate your grade point average (GPA) based on class grades and credits.
Open Calculator →Weighted Grade Calculator
Calculate your current class grade based on assignment categories and weights.
Open Calculator →Word & Paragraph Counter
Analyze text blocks for character count, words, paragraphs, and reading times.
Open Calculator →