Scientific Calculator
A powerful scientific calculator with trigonometric functions, logarithms, and more.
Percentage Calculator
Calculate percentages easily with multiple calculation modes.
Margin & Markup Calculator
Calculate gross margin, markup percentage, and profit for your business pricing.
ROI Calculator
Calculate Return on Investment (ROI) and annualized returns for any investment.
Compound Interest Calculator
Calculate how your money grows with compound interest over time.
Loan / Mortgage Amortization Calculator
Calculate monthly payments, total interest, and view full amortization schedule for any loan or mortgage.
Salary / Hourly Wage Converter
Convert between hourly, daily, weekly, monthly, and annual salary rates instantly.
Freelance Hourly Rate Calculator
Calculate the minimum hourly rate you need to charge as a freelancer to meet your income goals.
Stripe Fee Calculator
Calculate Stripe processing fees and find out exactly how much to charge to receive your desired amount.
PayPal Fee Calculator
Calculate PayPal processing fees and find out exactly how much to charge to receive your desired amount.
Flea Market Fee & Profit Calculator
Calculate fees, net profit, and ROI for Mercari, Rakuma, PayPay Flea Market, eBay, and more.
Currency Converter
Convert between world currencies with live exchange rates. Updated regularly.
Crypto to Fiat Converter
Convert cryptocurrency to fiat currency with live prices from CoinGecko.
Bitcoin Satoshi to USD Converter
Convert between Bitcoin, Satoshi, mBTC, bits and fiat currency with live BTC price.
Tax / VAT Calculator
Add or remove tax/VAT from any price. Supports all tax rates worldwide.
Discount Calculator
Calculate discounts, sale prices, and savings instantly. Works for any percentage off.
Tip Calculator
Calculate tip amount and split the bill evenly among friends.
Split the Bill Calculator
Split a restaurant bill equally or by custom amounts among friends. Includes tip calculation.
Cost of Living Comparison Calculator
Compare cost of living between major cities worldwide. Find the equivalent salary needed to maintain your lifestyle.
Inflation Calculator
Calculate the effect of inflation on purchasing power. See how much money from the past is worth today.
Break-Even Analysis Calculator
Calculate how many units you need to sell to cover your costs and start making profit.
CPM / CPC / CTR Advertising Calculator
Calculate CPM, CPC, CTR, and CPA metrics for your digital advertising campaigns.
Google AdSense Revenue Estimator
Estimate your Google AdSense earnings based on page views, RPM, CTR, and CPC.
YouTube Ad Revenue Calculator
Estimate your YouTube ad earnings based on views, RPM, and ad impression rate.
Rule of 72 Calculator
Calculate how long it takes to double your investment using the Rule of 72.
CAGR Calculator
Calculate Compound Annual Growth Rate (CAGR) to measure investment or business growth over time.
Auto Loan Calculator
Calculate your monthly car payment, total interest, and full amortization schedule for any auto loan.
Date Difference Calculator
Calculate the exact number of days, weeks, months, and years between two dates instantly.
Add/Subtract Days Calculator
Add or subtract days, weeks, months, or years from any date instantly. Find resulting dates with day of week info.
Age on a Specific Date Calculator
Calculate your exact age on any specific date. Find your age in years, months, and days, plus next birthday countdown and fun facts.
Unix Timestamp Converter
Convert Unix timestamps to human-readable dates and vice versa. Supports seconds and milliseconds with multiple timezone representations.
Time Zone Converter & Meeting Planner
Convert times across multiple time zones and plan meetings with a business hours grid. Supports all IANA time zones.
Work Hours / Timesheet Calculator
Calculate weekly work hours and estimated pay from your timesheet. Enter start/end times and breaks for each day.
BMI Body Mass Index Calculator
Calculate your Body Mass Index (BMI) instantly. Supports metric and imperial units with BMI category and healthy weight range.
BMR & TDEE Calculator
Calculate your Basal Metabolic Rate (BMR) and Total Daily Energy Expenditure (TDEE). Supports Mifflin-St Jeor and Harris-Benedict formulas with metric and imperial units.
Pregnancy Due Date Calculator
Calculate your pregnancy due date using LMP, conception date, or IVF transfer date. Get gestational age, trimester info, and key pregnancy milestones.
Ovulation Calculator
Calculate your ovulation date, fertile window, and next period. Track your cycle and plan ahead with this free ovulation calculator.
Macros Calculator
Calculate your ideal daily macronutrients — protein, fat, and carbs — based on your body stats, activity level, and fitness goal. Free macro nutrient calculator with meal split.
Running Pace Calculator
Calculate your running pace, finish time, or distance. Supports km and miles with race time predictions for 5K, 10K, half marathon, and marathon.
1RM One-Rep Max Calculator
Calculate your one-rep max (1RM) for any lift using multiple formulas (Epley, Brzycki, Lombardi, Mayhew). Supports kg and lbs with a full percentage table for training zones.
Blood Alcohol Content (BAC) Calculator
Calculate your Blood Alcohol Content (BAC) using the Widmark formula. Enter gender, weight, drinks consumed, and time elapsed to estimate your BAC and time to sober up.
Fertility Window Calculator
Calculate your fertile window, ovulation day, and conception probability by day. Detailed fertility tracking with next 6 cycles forecast.
GPA Calculator
Calculate your cumulative GPA using your course grades and credit hours. Supports 4.0 and percentage scales. Free online GPA calculator.
Final Grade Calculator
Calculate what score you need on your final exam to reach your desired grade, or find out your overall course grade based on weighted assignments.
Fuel Economy Calculator
Calculate fuel economy in MPG, L/100km, and km/L. Estimate fuel needed and trip cost for any distance.
Trip Fuel Cost Calculator
Calculate trip fuel cost, total fuel needed, cost per passenger, and cost per mile/km. Supports round trips, multiple stops, and car comparison.
Metric to Imperial Unit Converter
Convert metric units to imperial units instantly — length, weight, volume, area, and speed conversions in one free tool.
Temperature Converter
Convert between Celsius, Fahrenheit, Kelvin, Rankine, and Réaumur instantly. Free online temperature converter with visual thermometer scale and reference table.
Length/Distance Converter
Convert between metric and imperial length units instantly.
Weight/Mass Converter
Convert between metric and imperial weight and mass units instantly.
Golden Ratio Calculator
Calculate golden ratio proportions instantly. Enter any value to find its golden ratio counterpart for design, art, and nature.
Flight Distance Calculator
Calculate the great-circle distance between two airports or cities. Get distance in km and miles plus estimated flight time based on a cruising speed of 900 km/h.
Coordinates to Address Finder
Convert GPS coordinates (latitude & longitude) to a full address using free reverse geocoding. Instantly find any location on Earth.
Address to Coordinates
Convert any address or place name to GPS coordinates (latitude & longitude) using free forward geocoding. Instantly find the exact location of any place on Earth.
IP Address to Location Map
Look up the geographic location of any IP address. See city, country, ISP, timezone, and view it on an interactive map. Free IP geolocation tool.
Math Equation Solver
Free online math equation solver. Solve linear equations, quadratic equations, and evaluate mathematical expressions step-by-step. Entirely client-side.
Aspect Ratio Calculator
Calculate and simplify aspect ratios. Find missing dimensions for 16:9, 4:3, 1:1, and more. Free online aspect ratio calculator.
Video Bitrate Calculator
Calculate recommended video bitrate and estimated file size for any resolution, frame rate, and codec. Free online video bitrate calculator.
Audio Bitrate Calculator
Calculate audio bitrate, file size, and choose the right quality settings for MP3, AAC, FLAC, WAV, OGG, and OPUS. Free online audio bitrate calculator.
Storage Size Converter
Convert between bits, bytes, KB, MB, GB, TB, and more. Supports both decimal (SI) and binary (IEC) units. Free online storage size converter.
Bandwidth / Download Time Calculator
Calculate how long it will take to download a file based on your internet connection speed.
Data Transfer Rate Converter
Convert between data transfer rates including Mbps, MB/s, Gbps and more.
A/B Test Sample Size Calculator
Calculate the required sample size for statistically valid A/B tests. Set your baseline conversion rate, minimum detectable effect, confidence level, and power to get accurate results instantly.
Statistical Significance Calculator
Calculate whether your A/B test results are statistically significant. Enter visitor and conversion counts to get p-value, z-score, and confidence level instantly.
NPS Calculator
Calculate your Net Promoter Score (NPS) instantly. Enter promoter, passive, and detractor counts or paste raw survey scores to get your NPS and category breakdown.
Customer Churn Rate Calculator
Calculate your customer churn rate, retention rate, and key business metrics instantly. Free, real-time calculator with industry benchmarks.
CLV Calculator
Calculate Customer Lifetime Value (CLV/LTV) using Simple, Traditional, or Predictive methods. Free real-time calculator with LTV:CAC ratio.
Monthly Recurring Revenue (MRR) Calculator
Calculate your Monthly Recurring Revenue (MRR), track new MRR, churn, and growth rate for your SaaS business.
Burn Rate & Runway Calculator
Calculate your startup's gross burn rate, net burn rate, and cash runway to know how long your funding will last.
Employee Turnover Rate Calculator
Calculate your employee turnover rate to understand workforce retention and identify areas for improvement.
Meeting Cost Calculator (Time is Money)
Calculate the real cost of your meetings based on attendees, hourly rates, and duration. Make every meeting count.
Salary Take-Home Pay Calculator
Estimate your take-home pay after taxes and deductions. Supports US, UK, Canada, Australia, Japan, Germany, and France.
Online Calculators for Every Need
From quick percentage calculations to detailed financial projections, our calculator tools cover a wide range of everyday mathematical needs. Each calculator provides instant results with full precision, and many include step-by-step breakdowns so you can understand the logic behind the numbers. All calculations run locally in your browser — no data is sent to any server.
Getting the Most from Online Calculators
- For financial calculations like loan payments and compound interest, double-check your input units — are you entering annual or monthly interest rates?
- Use the percentage calculator for quick markup/markdown calculations when shopping or pricing products.
- BMI calculations are a screening tool, not a diagnosis. Consider factors like muscle mass and body composition alongside BMI results.
- When converting units, pay attention to precision. Our tools maintain full decimal precision for scientific and engineering calculations.
- Bookmark your most-used calculators for quick access — they load instantly with no sign-up required.
Related Articles
Frequently Asked Questions
How accurate are the calculations?
Our calculators use JavaScript's 64-bit floating-point arithmetic, which provides approximately 15-17 significant decimal digits of precision. This is more than sufficient for everyday calculations and most professional uses.
Can I use these for professional or academic work?
Yes. The mathematical formulas used are standard and well-documented. However, for critical financial or engineering decisions, we recommend verifying results with a second source.
Do the calculators work offline?
Once the page is loaded, most calculators work without an internet connection since all computation happens in your browser.