Calculators
Specialized calculators for developers and finance. Built for performance and privacy. Instant processing directly in your browser.
Percentage Calculator
Calculate percentage of a number, percentage change, what percent X is of Y, and work backward from a percentage — all in one tool.
Loan Calculator
Calculate monthly EMI, total interest paid, and view a full month-by-month amortization schedule for any loan.
Investment Calculator
Calculate compound interest returns for lump-sum or monthly SIP investments with a year-by-year growth chart, wealth breakdown, and Rule of 72 insight.
Age Calculator
Find your exact age in years, months, days, weeks, and total hours from any date, with a next birthday countdown.
Unix Timestamp Converter
Convert Unix timestamps to human-readable dates and back. Supports seconds and milliseconds with a live Unix timestamp clock.
Number Base Converter
Convert any number between binary, octal, decimal, and hexadecimal bases instantly with input validation and one-click copy.
BMI Calculator
Calculate your Body Mass Index in metric or imperial units with a visual gauge, BMI category, and healthy weight range.
Aspect Ratio Calculator
Calculate width, height, or ratio from any two values. Supports common presets like 16:9, 4:3, and 1:1 with a visual preview.
Color Contrast Calculator
Check foreground and background color contrast ratios against WCAG AA and AAA accessibility standards with a live preview.
Tip Calculator
Calculate tip, total bill, and split between people.
Discount Calculator
Find discounted price and savings from a % off.
Freelance Hourly Rate Calculator
Calculate your perfect freelance hourly rate based on target income, expenses, and billable hours.
Twitch Money Calculator
Calculate streamer payouts for Bits and Subs, and estimate viewer costs.
Substack Revenue Calculator
Calculate exact Substack and Stripe fees to find your true net subscription revenue.
Kick Payout Calculator
Calculate your exact streamer earnings using Kick's 95/5 revenue split.
Discord Boost Calculator
Calculate how many boosts you need to reach the next server level and exactly how much it will cost.
Patreon Fee Calculator
Calculate Patreon platform and payment processing fees based on your membership tier.
GST / VAT Calculator
Add or remove GST/VAT from any amount.
Scientific Calculator
Full scientific calculator with history.
Margin Calculator
Calculate gross margin, markup, and profit.
ROI Calculator
Calculate Return on Investment percentage.
Attendance Calculator Online
Calculate your attendance percentage online and find out how many classes you can skip or must attend to reach your 75%, 80%, or custom target.
CGPA to Percentage Calculator
Convert CGPA to percentage (or back) for VTU, Anna University, KTU, Mumbai University and more grading scales.
GPA Calculator
Calculate semester GPA from subject grades and credit hours. Supports US 4.0 and Indian 10.0 grading scales with live grade classification.
Timetable Maker
Create beautiful weekly timetables for school, college, work, or personal use. Add subjects, color-code periods, and export to PDF or PNG — 100% free, no sign-up.
Free Calculators for Everyday Tasks
FluxToolkit calculators provide rapid, precise answers to specialized math problems. From financial forecasting like ROI and profit margins to health metrics like BMI and technical conversions like Unix timestamps, these tools save you from setting up complex spreadsheet formulas.
Financial and Business planning
Entrepreneurs and marketers rely on our ROI Calculator, Profit Margin Calculator, and Discount Calculator to price products, forecast campaign profitability, and manage retail sales effectively.
Everyday math made easy
The Percentage Calculator takes the headache out of tip calculations, tax additions, and percent-change comparisons. The Age Calculator provides your exact age down to the days and months.
Technical and Developer calculations
Convert complex epochs with the Unix Timestamp Converter, translate data across binary and hex with the Number Base Converter, and calculate exact dimensions for video and images using the Aspect Ratio Calculator.
Calculators FAQ
What is the difference between markup and profit margin?
Markup is the percentage added to your cost to get the selling price, while profit margin is the percentage of the selling price that is profit. Our Margin Calculator helps you determine the correct selling price to achieve your desired margin.
How accurate is the Age Calculator?
Highly accurate. It accounts for leap years and varying month lengths to give you a precise breakdown of years, months, weeks, and days between a birth date and today (or any custom target date).
Does the GST Calculator work for my country?
The GST Calculator allows you to input custom percentage rates, making it adaptable to almost any country's Goods and Services Tax, VAT, or standard sales tax systems.
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