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JSON Formatter
Format, prettify, and validate JSON text.
Enter values and calculate the result.
About the JSON Formatter
The JSON Formatter validates JSON and converts it into readable indented formatting.
How to use it
Paste JSON text, press Format JSON, and copy the formatted result.
Formula / Explanation
The tool validates JSON and adds two-space indentation without changing numbers, strings, key order, or duplicate keys.
Example
{"name":"OnlineCalMaster"} becomes a neatly formatted JSON object.
Does it fix invalid JSON?
No. It reports invalid JSON so you can correct it.
Is my JSON uploaded?
No. Formatting happens in your browser.
Can I copy the result?
Yes. Use the Copy button after formatting.
Basic Calculator
Perform basic math operations like addition, subtraction, multiplication, and division. Includes memory functions and square root support.
Scientific Calculator
Perform complex calculations including sine, cosine, tangent, logarithms, constants like pi and e, and exponent support.
Unit Converter
Convert between units of length, weight, and temperature easily. Supports metric and imperial systems for accurate conversions.
Age Calculator
Calculate your exact age in years, months, and days based on your birthdate. Also shows countdown to your next birthday!
Date Difference Calculator
Find the number of days between two dates. Useful for planning events, calculating durations, or tracking timelines.
Time Difference Calculator
Calculate the difference between two times or datetime values. Shows total hours, minutes, and seconds between timestamps.
Percentage Calculator
Quickly calculate percentages of any value. Great for discounts, grades, and general math problems.
Percentage Change Calculator
Determine the percentage increase or decrease between two numbers. Useful for financial analysis and performance tracking.
Tip Calculator
Split bills and calculate tips effortlessly. Enter the bill amount and desired tip percentage to get total cost instantly.
VAT / Discount Calculator
Add or remove VAT (Value Added Tax) or discounts from prices. Perfect for shoppers, business owners, and accountants.
About the VAT Calculator
This VAT calculator helps you add tax to a net price or remove VAT from a tax-inclusive price.
How to use it
Enter the amount, type the VAT rate, then choose Add VAT or Remove VAT.
Formula
Add VAT: Total = Amount x (1 + Rate / 100). Remove VAT: Net = Total / (1 + Rate / 100).
Example
For Rs. 10,000 at 18 percent VAT, the VAT-inclusive total is Rs. 11,800.
Can I use this for sales tax?
Yes. It works for any percentage-based tax similar to VAT.
What does Remove VAT mean?
It calculates the original net price from a price that already includes VAT.
Can the VAT rate be changed?
Yes. Enter the tax rate that applies to your country or invoice.
Loan EMI Calculator
Calculate monthly loan payments, total payment, and total interest for personal, vehicle, housing, or business loans.
Enter loan details and calculate your monthly EMI.
About the Loan EMI Calculator
This calculator estimates the fixed monthly payment for a loan and shows total payment and total interest.
How to use it
Enter the loan amount, annual interest rate, loan term, and choose whether the term is in years or months.
Formula
EMI = P x R x (1 + R)^N / ((1 + R)^N - 1). For 0 percent interest, EMI = P / N.
Example
A Rs. 500,000 loan for 5 years at 10 percent interest gives an estimated monthly EMI.
What is EMI?
EMI means Equated Monthly Installment, the fixed amount paid each month.
Does this include fees?
No. It calculates loan payment from principal, rate, and term only.
Can I calculate a 0 percent loan?
Yes. The calculator divides the loan amount by the number of months.
Mortgage Calculator
Estimate home loan payments with down payment, interest, taxes, insurance, and total loan cost breakdown.
Enter home loan details and calculate your monthly mortgage payment.
Compound Interest Calculator
Project savings and investments with compound growth, optional monthly contributions, and clear interest breakdowns.
Enter investment details and calculate compound growth.
BMI Calculator
Calculate body mass index with metric or imperial units and see a clear health category range.
Enter weight and height to calculate BMI.
About the BMI Calculator
This BMI calculator estimates body mass index from weight and height, then shows the common BMI category.
How to use it
Enter your weight and height, choose the correct units, and press Calculate.
Formula
BMI = weight in kilograms / (height in meters x height in meters).
Example
A person who weighs 70 kg and is 1.75 m tall has a BMI of about 22.9.
Is BMI a medical diagnosis?
No. BMI is a general screening number and does not replace medical advice.
Can I use pounds and feet?
Yes. The calculator converts imperial units before calculating BMI.
What is a normal BMI range?
A BMI from 18.5 to 24.9 is commonly considered the normal range for adults.
Discount Calculator
Calculate sale price, savings, optional tax, and final payable amount for shopping or business pricing.
Enter price and discount to calculate savings.
Fuel Cost Calculator
Estimate total fuel needed and travel fuel cost from distance, vehicle efficiency, and fuel price per liter.
Enter trip and fuel details to calculate total fuel cost.
About the Fuel Cost Calculator
This calculator estimates how much fuel a trip needs and the total cost based on distance, efficiency, and fuel price.
How to use it
Enter distance, your vehicle fuel efficiency in kilometers per liter, and the fuel price per liter.
Formula
Fuel needed = Distance / Fuel efficiency. Total cost = Fuel needed x Fuel price per liter.
Example
For 100 km at 20 km/l and Rs. 300 per liter, fuel needed is 5 liters and cost is Rs. 1,500.
What fuel efficiency unit is used?
The calculator uses kilometers per liter.
Can I use it for bike trips?
Yes. It works for cars, bikes, vans, and any vehicle using distance and fuel efficiency.
Does it include tolls or parking?
No. It calculates only fuel usage and fuel cost.
Profit Margin Calculator
Calculate profit amount, profit margin, and markup percentage from cost price and selling price.
Enter cost and selling price to calculate profit margin.
About the Profit Margin Calculator
This calculator shows profit amount, profit margin, and markup from cost price and selling price.
How to use it
Enter the cost price and selling price, then press Calculate.
Formula
Profit = Selling price - Cost price. Margin = Profit / Selling price x 100. Markup = Profit / Cost price x 100.
Example
If cost is Rs. 100 and selling price is Rs. 150, profit is Rs. 50, margin is 33.33 percent, and markup is 50 percent.
What is profit margin?
Profit margin shows profit as a percentage of selling price.
What is markup?
Markup shows profit as a percentage of cost price.
Can profit be negative?
Yes. If selling price is lower than cost price, the result shows a loss.
Break-Even Calculator
Find how many units you need to sell to cover fixed costs and calculate break-even sales value.
Enter business cost details to calculate break-even point.
About the Break-Even Calculator
This calculator estimates how many units must be sold to cover fixed and variable costs.
How to use it
Enter fixed costs, selling price per unit, and variable cost per unit.
Formula
Break-even units = Fixed costs / (Selling price per unit - Variable cost per unit).
Example
If fixed costs are Rs. 1,000, price is Rs. 50, and variable cost is Rs. 30, break-even is 50 units.
What are fixed costs?
Fixed costs are costs that do not change directly with each unit sold, such as rent or salaries.
What is variable cost?
Variable cost is the cost linked to each unit, such as materials or packaging.
Why must price be higher than variable cost?
Each sale must contribute something toward fixed costs; otherwise break-even cannot be reached.
ROI Calculator
Measure investment performance by calculating net profit and return on investment percentage.
Enter investment and final value to calculate ROI.
About the ROI Calculator
This ROI calculator measures return on investment by comparing the investment amount with the final value.
How to use it
Enter the original investment amount and the final value or return amount.
Formula
Net profit = Final value - Investment amount. ROI = Net profit / Investment amount x 100.
Example
If you invest Rs. 1,000 and the final value is Rs. 1,250, net profit is Rs. 250 and ROI is 25 percent.
What does ROI mean?
ROI means return on investment, a percentage that shows gain or loss compared with the amount invested.
Can ROI be negative?
Yes. If the final value is lower than the investment, ROI is negative.
Does ROI include time?
No. This calculator shows simple ROI and does not annualize the return.
Simple Interest Calculator
Calculate simple interest and total amount from principal, annual interest rate, and time in years.
Enter principal, rate, and time to calculate simple interest.
About the Simple Interest Calculator
This calculator finds interest earned or charged using principal, annual rate, and time in years.
How to use it
Enter the principal amount, annual interest rate, and time period in years.
Formula
Simple interest = Principal x Rate x Time / 100. Total amount = Principal + Interest.
Example
For Rs. 1,000 at 10 percent for 2 years, interest is Rs. 200 and total amount is Rs. 1,200.
What is simple interest?
Simple interest is calculated only on the original principal amount.
Is this compound interest?
No. Compound interest adds interest to the balance over time.
Can I enter decimal years?
Yes. You can use values such as 1.5 years for one year and six months.
Volume Calculator
Calculate volume for cubes, boxes, cylinders, spheres, and cones with clear unit-based results.
Select a shape and enter dimensions to calculate volume.
Area Calculator
Calculate area for common 2D shapes with dynamic fields, formulas, and clean unit-based results.
Select a shape and enter dimensions to calculate area.
How to Use
Paste JSON text, press Format JSON, and copy the formatted result.