Free Online Calculators
Finance, health, and everyday math — ROI, margins, EMI, mortgage, BMI, fuel cost, inflation, savings goals, and more — free in your browser.
Browse every free calculators on FileToolsHub. Open a tool to upload or paste your input, run the action, and download or copy the result — no installation and no paid plan required for everyday use.
72 free online tools
Free online calculators
FileToolsHub calculators run entirely in your browser — finance (ROI, profit margin, markup, break-even, simple interest, APR, inflation, sales tax, commission, overtime, savings goals, debt payoff, Rule of 72, pay raise, hourly↔salary, net worth, stacked discounts), health (BMI, BMR/TDEE, calorie deficit, pregnancy due date, ovulation, water intake, protein, macros, Navy body-fat, 1RM), and everyday helpers (fuel cost, electricity bill, fraction converter, hours adder, tip split, grade weights, aspect ratio, DPI, hours↔decimal, timezone meeting planner, dice roller), plus percentage, tip, units, EMI, mortgage, VAT, currency, week number, and countdown.
These tools use standard formulas only. Loan/EMI/mortgage and debt estimates exclude taxes, insurance, and fees. Health and fertility tools are informational, not medical advice. Currency defaults are illustrative. Results are for everyday planning — not professional financial, tax, or medical advice.
Browse /calculator or the HTML sitemap for every calculator URL. New Wave 1 tools are linked from related tools and featured in the Calculators hub.
- Estimate ROI, margin, markup, or break-even units
- Plan savings goals or debt payoff timelines
- Check BMI, BMR/TDEE, or calorie deficit
- Estimate EMI, mortgage, or loan payments
- Add sales tax or VAT/GST to a price
- Estimate fuel trip cost or electricity bill
- Convert fractions; roll dice; Rule of 72
- Split a restaurant bill with tip
All calculators
ROI Calculator
Calculate return on investment from amount invested and amount returned.
BMI Calculator
Calculate body mass index from weight (kg) and height (cm) with WHO adult categories.
Debt Payoff Calculator
Estimate months, total paid, and interest to clear a balance with fixed monthly payments.
Profit Margin Calculator
Find profit and margin percent from revenue and cost.
Savings Goal Calculator
Estimate months to reach a savings goal with monthly contributions and optional return rate.
Fuel Cost Calculator
Estimate trip fuel use and cost using L/100km or MPG plus fuel price.
Compound Interest Calculator
Project savings growth with compound interest and optional regular contributions.
EMI Calculator
Calculate equated monthly installments (EMI) for a fixed-rate loan or purchase plan.
Mortgage Calculator
Estimate mortgage payments from property price, down payment, rate, and term.
Loan Calculator
Estimate monthly payments, total interest, and payoff cost for a fixed-rate amortizing loan.
VAT Calculator
Add or extract VAT/GST from an amount using a percentage rate.
Pay Raise Calculator
Calculate the raise amount and new pay from current pay and raise percent.
BMR & TDEE Calculator
Estimate basal metabolic rate and daily calories (TDEE) using Mifflin–St Jeor.
Sales Tax Calculator
Add sales tax to a net price or extract tax from a tax-inclusive total.
Simple Interest Calculator
Calculate simple interest and total amount from principal, rate, and years.
Hourly to Salary Calculator
Convert an hourly wage to weekly, monthly, and annual salary estimates.
Salary to Hourly Calculator
Convert annual salary to an equivalent hourly rate from hours/week and weeks/year.
Net Worth Calculator
Subtract liabilities from assets for a quick net-worth snapshot.
Tip Split Calculator
Calculate tip, total bill, and equal per-person share.
Grade Calculator
Compute a weighted grade from scores and matching weights.
Macro Calculator
Split daily calories into protein, carbs, and fat grams from percent targets.
Aspect Ratio Calculator
Simplify width×height to a ratio like 16:9 and show the decimal.
Discount Stack Calculator
Apply multiple discounts in order to see the final price and total savings.
CAGR Calculator
Calculate compound annual growth rate from start value, end value, and years.
Sleep Cycle Calculator
Suggest wake times based on ~90-minute sleep cycles from your bedtime.
Pace Split Calculator
Generate even kilometer (or custom) splits from race distance and target pace.
Payback Period Calculator
Estimate how many years to recover an investment from steady annual cash flow.
Amortization Schedule Calculator
Calculate monthly loan payment and preview the amortization schedule.
Refinance Break-even Calculator
Find how many months until refinance closing costs are offset by lower payments.
Margin Markup Converter
Convert between profit margin percent and markup percent.
Calories from Macros
Convert protein, carb, and fat grams into total calories (4/4/9).
Ideal Weight Calculator
Estimate ideal body weight with the Devine formula from height.
VO2 Max Cooper Calculator
Estimate VO₂ max from a 12-minute Cooper run distance.
Tip on Taxed Bill Calculator
Calculate tip and grand total with tax, tipping on pre-tax or post-tax amount.
Unit Price Calculator
Find price per unit from pack price and quantity — compare grocery and bulk deals.
Monthly vs Annual Savings
Compare paying monthly vs yearly for a subscription and see which saves money.
Meeting Cost Calculator
Estimate the cost of a meeting from attendees, average hourly rate, and duration.
Percentage Calculator
Find X% of Y, what percent one number is of another, or percent change.
Tip Calculator
Calculate tip amount and split a bill between people.
Discount Calculator
Calculate sale price and savings from an original price and discount percent.
Unit Converter
Convert length, weight, temperature, area, volume, speed, and data storage units.
Number Base Converter
Convert numbers between binary, octal, decimal, and hexadecimal.
Date Difference
Calculate the number of days, weeks, and hours between two dates.
Age Calculator
Calculate age in years, months, and days from a date of birth.
Salary Converter
Convert between hourly, daily, weekly, monthly, and yearly pay.
Pace Calculator
Calculate running or walking pace, speed, and finish time from distance and time.
GPA Calculator
Calculate weighted GPA from course grades and credits on a 4.0, 5.0, or percentage scale.
Currency Converter
Convert between currencies using editable exchange rates (illustrative defaults vs USD).
Week Number
Find the ISO week number (1–53) for any date.
Countdown Timer
Live countdown to a target date and time — days, hours, minutes, and seconds.
Markup Calculator
Calculate selling price from cost and markup percent.
Break-Even Calculator
Estimate units needed to cover fixed costs given price and variable cost per unit.
APR / Effective Rate Calculator
Convert a nominal APR into an effective annual rate given compounding frequency.
Inflation Calculator
See how inflation changes the future value of money over a number of years.
Commission Calculator
Calculate sales commission from revenue and rate, with optional base pay.
Overtime Pay Calculator
Estimate regular and overtime pay from hourly rate, hours, OT threshold, and multiplier.
Calorie Deficit Calculator
Compare TDEE and intake to estimate daily/weekly deficit and rough kg change.
Pregnancy Due Date Calculator
Estimate a due date from the last menstrual period (LMP) using Naegele’s rule.
Ovulation Calculator
Estimate ovulation day and fertile window from period start and cycle length.
Time Zone Meeting Planner
Convert a meeting time between two fixed UTC offsets (no live DST lookup).
Hours & Minutes Adder
Add two durations in hours and minutes and see the total.
Electricity Bill Calculator
Estimate an electricity bill from kWh usage, rate per kWh, and optional fixed fee.
Fraction Converter
Convert fractions to decimal/percent, or approximate a decimal as a fraction.
Dice Roller
Roll one or more dice with a chosen number of sides using secure browser randomness.
Rule of 72 Calculator
Estimate years for an investment to double at a given annual return percent.
Water Intake Calculator
Estimate daily water needs from body weight and activity minutes.
One Rep Max Calculator
Estimate one-rep max (1RM) from a weight and rep count using the Epley formula.
Protein Intake Calculator
Estimate daily protein grams from body weight and grams-per-kg target.
DPI Calculator
Calculate DPI/PPI from pixel count along one side and physical size in inches.
Body Fat Navy Calculator
Estimate body-fat percent with the US Navy circumference method (informational).
Hours to Decimal
Convert hours and minutes to decimal hours for timesheets.
Decimal to Hours
Convert decimal hours back to hours and minutes.
Looking for something else? Browse the full sitemap.
Why use FileToolsHub for calculators?
FileToolsHub keeps calculators in one place so you do not bounce between unrelated converter sites. Each tool page explains how the workflow works, lists benefits, and answers common questions so you can finish the job without searching for instructions.
When you need a different format or a follow-up step, related tools and category links make it easy to continue — for example merge then compress, or format JSON then validate. Browse the sitemap if you want a full alphabetical-style list by category.
Every tool in this category is free for unlimited everyday use. Prefer mobile? The same pages work in phone and tablet browsers so you can convert a file or format text when you are away from your desktop.