Instant Results
Need a quick calculation? Pick a tool, enter your numbers, and get the answer right away. No sign-up, no downloads, no waiting.
Try our most popular tools like the percentage calculator or the ROI calculator.
Find what percent a number is, calculate percentage change, or get a percentage of any value.
Calculate PercentagesEnter the original price and the discount to see exactly how much you save and what you pay.
Calculate DiscountsEnter your height and weight to find your Body Mass Index and what it means for your health.
Check Your BMIEnter what you invested and what you got back to find out if it was worth it.
Calculate ROI
Most of us run into quick math problems every day — figuring out a tip, checking if a deal is actually good, or making sure a business decision makes financial sense. Searching for a formula and doing the math manually takes time and leaves room for mistakes.
That's why dedicated online calculators are so popular. You put in your numbers and get the answer right away, without setting up a spreadsheet or remembering how a formula works.
At Calqora, each calculator does one job and does it well. The interface stays simple so you can focus on the result, not on figuring out how to use the tool.
Percentage questions come up constantly — in shopping, at work, in school, and in everyday decisions. What is 20% of 85? How much did the price go up? What percentage of the budget is left?
Instead of doing the math by hand, you can use our percentage calculator to get an instant, accurate answer. Just choose the type of question and fill in the numbers.
It handles three common scenarios: finding a percentage of a number, figuring out what percent one number is of another, and calculating the percentage change between two values.
ROI (Return on Investment) is one of the most useful numbers in business. It tells you whether the money you spent actually generated a return. According to Investopedia, ROI is a key metric used to evaluate investment efficiency.
The formula is straightforward — gain minus cost, divided by cost — but doing it manually for multiple scenarios takes time. Our ROI calculator lets you run the numbers quickly and compare different investments side by side.
Whether you're evaluating a marketing campaign, a piece of equipment, or a business project, knowing the ROI helps you make better decisions with your money.
People use online calculators for all kinds of everyday situations. A student checks what grade they need on the final exam. A shopper figures out which deal actually saves more money. A small business owner calculates whether a new investment made sense. A person trying to get healthier checks their BMI to see where they stand.
What these situations have in common is that they all require a quick, reliable answer — not a long explanation, not a complex spreadsheet. Just a number you can trust and act on.
That's what Calqora is built for. Each tool is focused on one type of calculation, designed to be fast on any device, and free to use without any account or payment.
The percentage calculator on Calqora handles the three most common percentage questions people search for:
What is X% of a number? For example: what is 15% of 240? This comes up when calculating tips, taxes, discounts, or commission.
X is what percent of Y? For example: 36 is what percent of 240? This is useful for figuring out test scores, budget percentages, or market share.
Percentage change from one number to another. For example: a product went from $40 to $52 — that's a 30% increase. Useful for tracking price changes, sales growth, or weight loss progress.
Each scenario has its own input fields, so you only fill in what's relevant to your question.
When a store advertises 35% off, it's not always obvious how much you're saving in dollars or what you'll actually pay at checkout. The discount calculator makes it clear instantly.
Enter the original price and the discount percentage. The calculator shows you the amount saved and the final price. It's useful for comparing deals, setting sale prices for your own products, or just making sure you're getting what you think you're getting.
It works on any device, so you can pull it up right in the store before you buy.
BMI (Body Mass Index) is a simple number calculated from your height and weight. It's not a perfect measure of health, but it's a widely used starting point for understanding whether your weight is in a healthy range for your height.
The BMI calculator uses the standard formula defined by the CDC. Enter your height and weight and you'll see your BMI along with what category it falls into: underweight, normal, overweight, or obese.
It supports both metric and imperial units, so you can use the measurements you're already comfortable with.
Before spending money on something — an ad campaign, a new piece of equipment, a course, a product — it helps to know what return you can expect. And after the fact, it's worth knowing whether it paid off.
The ROI calculator takes two inputs: how much you spent and how much you got back. It calculates the return on investment as a percentage and tells you whether the result was positive or negative.
It's a straightforward tool for anyone making financial decisions, from freelancers evaluating their marketing spend to small business owners comparing investment options.
We're working on adding more calculators based on what people search for most. Coming soon: a tip calculator, an age calculator, a loan interest calculator, and a days-between-dates calculator.
If there's a specific calculator you'd like to see on Calqora, the tools are built to be practical and focused — so suggestions are always welcome.