Finance 193Math 200Health 91Practical 217Science 119Developer Tools 46AI Tools 43Sustainability 45Engineering 84Business 83

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Finance 193

For loans, interest, savings, taxes, and money decisions where guessing gets expensive.

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Mortgage CalculatorCalculate monthly mortgage payments with taxes and insurance.Compound Interest CalculatorCalculate how your savings will grow with compound interest.Tax Bracket CalculatorCalculate your federal tax bracket and effective tax rate with our free tax bracket calculator.ROI CalculatorCalculate return on investment (ROI) percentage to compare investment opportunities.
$40 000 Loan Payment For 10 YearsCalculate monthly payments for a $40,000 loan over 10 years.1 Mortgage CalculatorCalculate your monthly mortgage payment instantly. Enter loan amount, interest rate, and term to see exact pri…10 Year Loan Payment CalculatorCalculate your monthly payment on a 10-year loan. Enter loan amount and interest rate to see exact monthly pay…11 000 LoanCalculate your exact monthly payment on an $11,000 loan.25 Year LoanCalculate monthly payments and total cost for a 25-year loan.3 Year Loan CalculatorCalculate monthly payments for a 3-year loan. Enter loan amount and interest rate to see exact monthly payment…30000 Home LoanCalculate your monthly payment on a $30,000 home loan.401k Early Withdrawal CalculatorCalculate penalties and taxes on early 401k withdrawals.

Math 200

Arithmetic, algebra, geometry, and statistics. For when estimation is not good enough.

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Percentage CalculatorCalculate percentages, find what percent one number is of another, or determine percentage increases and decre…Average CalculatorCalculate the average (arithmetic mean) of any set of numbers instantly.Fraction CalculatorCalculate fraction addition, subtraction, multiplication, and division with automatic simplification.Standard Deviation CalculatorCalculate standard deviation from your data set. Enter numbers separated by commas to find population or sampl…
AAA Triangle CalculatorCalculate unknown sides and area of any triangle using three angles.AAS Triangle CalculatorCalculate the third angle and all side lengths of a triangle using two angles and one adjacent side (AAS).Abc Triangle CalculatorCalculate missing sides and angles of any triangle using the Law of Cosines and Law of Sines.Absolute Value CalculatorFind the absolute value of any real number instantly.Acute Triangle CalculatorEnter three side lengths to instantly classify your triangle and calculate all angles and area using the Law o…Adding Fractions CalculatorAdd fractions instantly with automatic simplification.Adding and Subtracting Fractions CalculatorCalculate fraction addition and subtraction with automatic simplification.Annual Percentage Rate CalculatorCalculate the true annual percentage rate (APR) of any loan including fees and charges.

Health 91

BMI, calories, hydration, sleep, and clinical calculators. Verify results with a professional.

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BMI CalculatorCalculate your Body Mass Index (BMI) instantly. Enter height and weight to see your BMI category and health ra…Calorie CalculatorCalculate daily calories needed to maintain, lose, or gain weight.TDEE CalculatorCalculate your Total Daily Energy Expenditure (TDEE) to determine exactly how many calories you burn each day…Heart Rate CalculatorCalculate your maximum heart rate and target heart rate zones for optimal exercise intensity.
Adderall Dosage CalculatorCalculate safe Adderall dosage recommendations based on age, weight, and condition severity.Adjusted Age CalculatorCalculate your premature baby's adjusted age in seconds.Adjusted Body Weight CalculatorCalculate adjusted body weight for medication dosing and clinical decisions.Adjusted Weight CalculatorCalculate adjusted body weight using the Devine formula.Age CheckerEnter your date of birth to instantly find your exact age in years, months, and days.Aleve Dosage CalculatorCalculate safe Aleve (naproxen sodium) dosage based on your weight and pain level.Arterial Age CalculatorFind out if your arteries are aging faster than you are.BMI CalculatorCalculate your Body Mass Index (BMI) instantly. Enter height and weight to determine if you're underweight, no…

Practical 217

Everyday converters for dates, units, travel, cooking, and life.

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Age CalculatorCalculate your exact age in years, months, and days.Date CalculatorCalculate days between dates, add or subtract time from any date.Hours CalculatorCalculate hours and minutes between two times. Get duration for timesheets, work shifts, project planning, or…
3D Render Time CalculatorCalculate how long your 3D render will take based on scene complexity, resolution, and hardware specs.A Real CalculatorA straightforward calculator for everyday arithmetic.Ab Test CalculatorCalculate statistical significance for your A/B test.Accounting Calculator OnlineCalculate gross profit, net profit, and key accounting ratios instantly.Add Time CalculatorAdd hours, minutes, and seconds together instantly.Adding Hours CalculatorAdd multiple time periods together to find total hours worked, project time, or combined durations.Age CalculatorCalculate your exact age in years, months, and days from your birth date.Age Difference CalculatorCalculate the exact age difference between two people in years, months, and days.

Science 119

Physics, chemistry, and earth science calculations for students and researchers.

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Density CalculatorCalculate density using mass and volume with our free density calculator.Half-Life CalculatorCalculate radioactive decay half-life, remaining quantity, and elapsed time.Gravitational Force CalculatorCalculate gravitational force between two objects. Enter masses and distance to find the attractive force in N…Molar Mass CalculatorCalculate the molar mass of any chemical compound. Enter your chemical formula and get the molecular weight in…
3 Phase Motor Amperage CalculatorCalculate 3 phase motor amperage from power, voltage, and efficiency.Acceleration CalculatorCalculate acceleration from velocity change and time.Acceleration CalculatorCalculate acceleration from velocity change and time, or find velocity and time from acceleration values.Activation Energy CalculatorCalculate activation energy from reaction rate constants at different temperatures.Air Density CalculatorCalculate air density from temperature, pressure, and humidity.Angle of Refraction CalculatorCalculate how light bends when passing between materials using Snell's law.Angular Acceleration CalculatorCalculate angular acceleration from change in angular velocity and time.Aperture Area CalculatorCalculate the light-collecting area of any circular aperture — telescope, camera lens, or antenna — instantly…

Developer Tools 46

Encoders, formatters, generators, and converters for developers.

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JSON FormatterFormat, validate, and prettify JSON data instantly.Base64 Encoder DecoderConvert text to Base64 encoding or decode Base64 strings back to readable text.Hash GeneratorGenerate secure MD5, SHA-1, SHA-256, and SHA-512 hashes from any text input.Regex TesterTest regular expressions against text instantly. Debug regex patterns, validate matches, and see capture group…
API Rate Limit CalculatorCalculate if your API usage stays within rate limits.Bandwidth CalculatorCalculate network bandwidth, data transfer rates, and download times.CDN Cost CalculatorCalculate CDN costs based on data transfer, bandwidth usage, and provider pricing.Cache Hit Ratio CalculatorCalculate cache hit ratio percentage from hits and misses.Code Complexity CalculatorCalculate cyclomatic complexity of your code. Enter lines of code, conditional statements, and loops to see co…Color Code ConverterConvert colors between hex, RGB, HSL, and HSV formats instantly.Color Contrast CheckerCheck color contrast ratios for web accessibility. Enter foreground and background colors to see if they meet…Cron Expression GeneratorGenerate cron expressions instantly. Set your schedule frequency, time fields, and get a ready-to-paste cron s…

AI Tools 43

Cost estimators, token calculators, and ROI tools for AI and LLM workflows.

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AI Token Cost CalculatorCalculate the exact cost of any AI API call by entering your token counts and provider pricing.LLM Token CalculatorFree LLM token calculator. Convert tokens to words, estimate API costs for GPT-4o, Claude 3.5, Gemini 1.5 Pro,…Context Window CalculatorFree context window calculator. Paste any text to see if it fits in GPT-4o (128K), Claude 3.5 (200K), or Gemin…Prompt Cost EstimatorCalculate the cost of AI prompts across different models.
AI API Budget CalculatorFree AI API budget calculator. Enter your monthly budget and usage pattern to see how many LLM calls you can a…AI Automation Opportunity FinderCalculate ROI potential for AI automation projects.AI Automation ROI CalculatorCalculate the ROI of AI automation projects. Compare implementation costs with savings from reduced labor, tim…AI Break Even CalculatorCalculate when your AI project becomes profitable. Enter development costs, monthly operating expenses, and re…AI Chatbot Value CalculatorCalculate your monthly savings and payback period from deploying an AI chatbot.AI Content Brief GeneratorGenerate a structured content brief instantly. Enter your topic, audience, and format to get section counts, w…AI Content Cost CalculatorCalculate exact costs for AI-generated content across providers.AI Cost CalculatorCalculate the exact cost of any AI API call. Enter token counts and pricing to see total spend per request in…

Sustainability 45

Carbon footprint, solar, energy, and environmental impact calculators.

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Carbon Footprint CalculatorCalculate your annual carbon footprint from transportation, energy use, and lifestyle.Solar ROI CalculatorCalculate solar panel return on investment with our free calculator.EV Charging Cost CalculatorCalculate electric vehicle charging costs with our free EV charging cost calculator.Rainwater Harvesting CalculatorCalculate annual rainwater collection potential from your roof.
Appliance Energy CalculatorCalculate appliance energy usage and cost. Enter power rating and usage hours to see daily, monthly, yearly co…Appliance Energy Cost CalculatorCalculate monthly and yearly electricity costs for any appliance.Battery Backup CalculatorCalculate how long your battery will power your devices.Battery Storage CalculatorCalculate how long your battery will power your devices.Calculate EnergyCalculate energy consumption and cost for any appliance or device.Carbon Offset CalculatorCalculate the cost and number of trees needed to offset your carbon footprint from flights, driving, and energ…Composting CalculatorCalculate ideal brown to green material ratios for composting.Composting Impact CalculatorCalculate how much CO2 you save by composting organic waste.

Engineering 84

Structural, electrical, mechanical, and civil engineering calculators.

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Ohm's Law CalculatorCalculate voltage, current, resistance, and power using Ohm's Law.Beam Deflection CalculatorCalculate maximum beam deflection instantly. Supports simply supported and cantilever beams with point or dist…
Ac Tonnage CalculatorCalculate the AC tonnage you need for any room or building.Aluminum Weight CalculatorCalculate the weight of aluminum stock in seconds. Enter dimensions and alloy, get pounds and kilograms instan…Beam Deflection CalculatorCalculate beam deflection for simply supported beams under point loads.Beam Load CalculatorCalculate beam load capacity and deflection for structural beams.Bearing Load CalculatorCalculate bearing static and dynamic loads for shaft design.Bolt Torque CalculatorCalculate bolt torque values using diameter, thread pitch, yield strength, and safety factor.Calculate My Roof SizeCalculate your roof size from footprint and pitch. Get total square footage, roofing squares, and material est…Carat Weight CalculatorCalculate the carat weight of a gemstone from its dimensions and shape.

Business 83

Revenue, margins, churn, CAC, LTV, and operational metrics for founders and operators.

Accounts Receivable Turnover CalculatorCalculate how quickly your business collects outstanding payments.Airbnb Profitability CalculatorCalculate your Airbnb rental profitability with monthly income, occupancy rates, and expenses.Arr CalculatorCalculate Annual Recurring Revenue (ARR) from monthly subscriptions, churn rate, and customer growth.Break Even Analysis CalculatorFind your break-even point in units and revenue. Enter fixed costs, variable costs, and price to see exactly w…Break Even Chart MakerFind your break-even point instantly. Enter fixed costs, variable costs, and price to see exactly how many uni…Break Even Graph MakerFind your break-even point instantly. Enter fixed costs, variable cost per unit, and price to see exactly when…Burn Rate CalculatorCalculate monthly burn rate, runway, and cash depletion timeline.Business Appraisal CalculatorEstimate your business value using revenue multiples, EBITDA multiples, and asset-based methods.
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