Frequently Asked Questions

Find answers to common questions about our calculators and services.

General Questions

What is OpportAI?

OpportAI is a free online calculator platform offering a wide range of calculators for finance, health, construction, and everyday use. Our tools are designed to be user-friendly and accurate.

Are the calculators free to use?

Yes, all calculators on OpportAI are completely free to use. No registration or subscription is required.

How accurate are the calculators?

Our calculators use standard formulas and algorithms to provide accurate results. However, for critical financial decisions, we recommend consulting with a professional.

Can I use these calculators on mobile devices?

Yes, all our calculators are fully responsive and work on smartphones, tablets, and desktop computers.

Financial Calculators

How does the Loan Calculator work?

Our loan calculator uses the standard amortization formula to calculate monthly payments based on principal, interest rate, and loan term. It also shows total interest paid and the full amortization schedule.

What is compound interest and how is it calculated?

Compound interest is interest calculated on the initial principal and also on the accumulated interest. Our calculator uses the formula A = P(1 + r/n)^(nt) where A is the future value, P is principal, r is annual interest rate, n is compounding frequency, and t is time.

How accurate is the Mortgage Calculator?

Our mortgage calculator provides estimates based on the principal, interest rate, and loan term. Actual payments may include additional costs like property taxes and insurance.

What is ROI and how do you calculate it?

ROI (Return on Investment) measures the profitability of an investment. It's calculated as (Net Profit / Cost of Investment) × 100. Our calculator makes this easy by asking for your initial investment and final value.

Health Calculators

How is BMI calculated?

BMI (Body Mass Index) is calculated as weight in kilograms divided by height in meters squared. The formula is: BMI = kg/m². Our calculator automatically converts your measurements and displays your BMI category.

What do BMI categories mean?

BMI categories are: Underweight (below 18.5), Normal weight (18.5-24.9), Overweight (25-29.9), and Obese (30 and above). Note that BMI is a general guideline and doesn't account for muscle mass or body composition.

How are daily calorie needs calculated?

Our calorie calculator uses the Harris-Benedict equation to estimate your basal metabolic rate (BMR) and then multiplies it by your activity level to determine your daily calorie needs.

Construction Calculators

How much concrete do I need?

Our concrete calculator determines the volume in cubic feet or yards based on your project's length, width, and depth. We recommend adding 10% for waste and spillage.

How do I calculate how many tiles I need?

Enter the area dimensions and tile size. Our calculator will determine the number of tiles needed, including a recommended waste factor for cutting and breakage.

How much paint do I need for a room?

Our paint calculator considers wall area, ceiling area, and subtracts areas for doors and windows. It then calculates the number of paint cans needed based on typical coverage rates.

How many bricks do I need for a wall?

Enter the wall dimensions and our calculator will estimate the number of standard bricks needed, including recommended mortar allowance.

Technical Questions

Is my data secure?

All calculations are performed locally in your browser. We don't store or transmit any personal data you enter into our calculators.

Do you save my calculation history?

No, we don't save any calculation history. All data remains on your device and is cleared when you refresh or close the page.

Can I bookmark specific calculations?

Yes, you can bookmark any calculator page. The input values you enter will remain in your browser's local storage for your convenience.

How can I report an error?

If you find any inaccuracies, please contact us through our contact page. We appreciate your feedback and continuously work to improve our tools.

Still have questions?

Can't find the answer you're looking for? Please contact our support team.