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BMI CalculatorHealth & Fitness
EMI CalculatorLoans & Debt
Compound Interest CalculatorInvesting & Retirement
Mortgage Payment EstimatorReal Estate
Percentage CalculatorEveryday Life
Retirement CalculatorInvesting & Retirement
Age CalculatorDate & Time
IPv4 Subnet CalculatorIP & Domain Tools
Calorie Burn CalculatorHealth & Fitness
Unit ConverterUnit Converters
ROI CalculatorBusiness & Marketing
Tip and Bill Split CalculatorEveryday Life
Money
Loans, investing, property, tax and crypto.
- Mortgage Payment Estimator
- Loan-to-Value (LTV) Calculator
- Mortgage Points Calculator
- Mortgage Refinance Calculator
- GST Calculator India (Add or Remove GST, CGST/SGST/IGST)
- US Federal Income Tax Calculator 2026
- Paycheck Calculator 2026 (Take-Home Pay After Tax)
- FICA Tax Calculator 2026 (Social Security and Medicare)
- Crypto Profit Calculator (with Trading Fees)
- Crypto Average Price Calculator (DCA Cost Basis)
- Satoshi Converter (BTC, Sats and Fiat)
- Staking Rewards Calculator (APR, APY and Compounding)
Business & Online
Margins, marketing, creators and online selling.
- ROI Calculator
- Markup and Margin Calculator
- Customer Lifetime Value Calculator
- Email Marketing ROI Calculator
- YouTube Money Calculator (Earnings from Views, CPM and RPM)
- TikTok Engagement Rate Calculator
- AdSense Revenue Calculator (Pageviews, CTR and CPC)
- Influencer Rate Card Calculator (What to Charge per Post)
Health & Body
Body metrics, nutrition, training and sport.
- Macro Calculator
- Water Intake Calculator
- Keto Macro Calculator
- Intermittent Fasting Calculator (16:8 and Other Schedules)
- Running Pace Calculator
- Race Time Predictor (Riegel)
- True Shooting Percentage Calculator (TS%)
- OPS Calculator (On-Base Plus Slugging)
Math & Tools
Equations, statistics, generators and everyday maths.
- Quadratic Equation Solver
- Triangle Calculator (Solve Any Triangle: SSS, SAS, ASA)
- Matrix Multiplication Calculator (3×3)
- Linear Equation Solver
- Permutation and Combination Calculator
- Probability Calculator (Two Events)
- Bayes' Theorem Calculator
- Binomial Distribution Calculator
- Scientific Calculator
- Graphing Calculator (Plot Functions Online)
- Random Number Generator
- Password Generator (Strong, Random, Private)
Science
Physics, chemistry, biology and the environment.
- Terminal Velocity Calculator
- Orbital Period Calculator (Kepler)
- Carnot Efficiency Calculator
- Speed of Sound Calculator
- Molar Mass Calculator (Molecular Weight from Formula)
- Grams to Moles Calculator (and Moles to Grams)
- Percent Composition Calculator (Mass Percent)
- Molality Calculator
- Punnett Square Calculator (Monohybrid and Dihybrid)
- Blood Type Calculator (Child's Possible ABO and Rh Type)
- Hardy-Weinberg Equilibrium Calculator
- Chi-Square Goodness-of-Fit Calculator (Genetic Ratios)
- Electricity Bill Calculator (Tiered Tariff)
- Home Solar System Size Calculator (kW and Panels)
- Solar Battery Size Calculator (Home Backup kWh)
- EV Range Calculator (Battery, Efficiency and Weather)
Tech & Engineering
Circuits, networks, radio, power and AI.
- Ohm's Law Calculator
- Electrical Power Calculator (Single and Three Phase)
- Resistors in Series and Parallel Calculator
- Capacitors in Series and Parallel Calculator
- Hosting Bandwidth Calculator
- Data Transfer Time Calculator
- Data Rate Converter (Mbps, MB/s, Gbps)
- Bandwidth Needed Calculator
- IPv4 Subnet Calculator
- CIDR Prefix to Hosts Calculator
- Subnet Mask to CIDR Prefix Calculator
- IP Address to Binary, Hex and Decimal Converter
- RSRP, RSRQ and RSSI Calculator
- SINR Calculator
- Thermal Noise and Receiver Sensitivity Calculator
- dBm Adder (Power Sum) Calculator
- Telecom Site Energy Cost Calculator (Grid, Diesel, Solar)
- Generator Fuel Consumption Calculator
- Genset Fuel Efficiency and Theft Check
- Generator Sizing Calculator (kVA)
- LLM API Cost Calculator (Tokens per Request to Monthly Cost)
- Words to Tokens Calculator (LLM Token Estimate)
- GPU Memory (VRAM) Calculator for LLMs
- Model File Size Calculator (Quantization)
Home & Life
Dates, building, cars, events, pets, travel and more.
- Percentage Calculator
- Tip and Bill Split Calculator
- Unit Price Calculator
- Pizza Size Comparison Calculator
- Board Foot Calculator (Lumber Volume and Cost)
- Drywall Mud, Tape and Screws Calculator
- Fence Post and Concrete Calculator
- Roof Pitch Calculator (Pitch, Angle and Roof Area)
- Trip Fuel Cost Calculator
- Towing Capacity Calculator (GCWR, Tongue Weight and Payload)
- Fuel Cost per Mile Calculator (Compare Two Vehicles)
- Engine Displacement Converter (cc, Cubic Inches, Liters)
- Wedding Alcohol Calculator (Wine, Beer and Liquor)
- Party Ice Calculator (How Much Ice per Guest)
- Pizza Order Calculator (Adults and Kids)
- Tiered Cake Serving Calculator
- GPA Calculator
- Test Score Calculator (Percentage and Letter Grade)
- Grade Curve Calculator (Curve Test Scores)
- Attendance Calculator (75% Rule: Classes to Attend or Skip)
- Dog Age Calculator
- Cat Age Calculator
- Dog Food Calculator (Calories and Cups per Day)
- Cat Food Calculator (Calories, Wet and Dry Food)
- Distance Between Coordinates Calculator (Latitude and Longitude)
- Flight Time Calculator (Duration and Arrival Time)
- Jet Lag Calculator (Recovery Days)
- Travel Budget Calculator (Trip Cost per Person)
- Exposure Value (EV) Calculator
- Depth of Field Calculator (Near, Far, Hyperfocal)
- Astrophotography Shutter Speed Calculator (500 Rule and NPF Rule)
- Photo Print Size Calculator (Pixels, DPI and Megapixels)
- Zakat Calculator (Cash, Gold, Silver and Business)
- Gold Zakat Calculator (Tola, Grams and Karat)
- Gold Price Calculator (Tola, Gram and Karat)
- Hijri Date Converter (Gregorian to Islamic and Back)
Converters
Every common unit, with the exact factor shown.
Recently added
Fuel Stops Calculator (Range and Refuels)Hotel vs Vacation Rental Cost CalculatorBaggage Size Calculator (Linear Inches and Weight)Sunrise and Sunset Calculator (Day Length and Twilight)Mileage Reimbursement Calculator (IRS Rate)Per Diem Calculator (Lodging and M&IE, 75% Travel Days)Altitude Oxygen Calculator (Air Pressure and Boiling Point)Hiking Time Calculator (Naismith's Rule)Road Trip Time Calculator (Driving Days and Breaks)Currency Exchange Fee Calculator (Hidden Markup)Travel Budget Calculator (Trip Cost per Person)Jet Lag Calculator (Recovery Days)Flight Time Calculator (Duration and Arrival Time)Distance Between Coordinates Calculator (Latitude and Longitude)Roman Numeral ConverterCase Converter (Upper, Lower, Title, camelCase)
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Every page shows the formula, a worked example and its sources, so you can check the result yourself.
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Results are checked against independent reference calculations, and every page is tested on small screens.
04
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Unit switching, currency symbols, shareable links and printable summaries on every calculator.
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