All tools
Free Online Calculators
Every calculator runs entirely in your browser — no signup, no uploads, no waiting. Pick a tool below; each page includes the formulas behind it and answers to the questions people actually ask.
Built on real market data
Currency Analysis Tools
These three go beyond converting a number: they measure what a conversion actually cost you, place today’s rate in decades of real history, and rank every transfer route by the money that arrives.
Money
Finance Calculators
Publishers
Creator & Ad Revenue Tools
Health
Health & Fitness Calculators
Everyday
Quick Math Tools
Developers
Developer Tools
A toolkit, not just one tool
The Calculators Behind Yunjx
Every tool on this page shares the same goals: instant results in your browser, no account to create, and plain language notes about what each number does and does not mean. The sections below group the calculators by the kind of decision they help with.
Money calculators for everyday decisions
Several of our tools focus on the numbers behind personal finance. The mortgage calculator breaks a home loan into principal and interest and shows the lifetime cost of different rates and terms, while the compound interest calculator demonstrates how earnings build on themselves across decades. The AdSense revenue calculator helps creators model the page views and ad rates that turn a website into income. Each one runs entirely in your browser, so you can experiment freely without creating an account or sending data anywhere.
Health and fitness estimators
The body focused tools translate simple inputs into context. The BMI calculator places your weight and height on the World Health Organization scale and shows the healthy range for your height, while the TDEE calculator estimates the daily calories you burn so you can plan around maintenance, loss, or gain. Both are screening aids rather than medical instruments, and both explain their limits plainly so the result is useful without being mistaken for a diagnosis.
The percentage calculator
The percentage calculator handles the three questions people actually need: finding a percentage of a number, working out what percentage one number is of another, and reversing a percentage change back to the original. It is the quiet workhorse behind discounts, tips, tax, and survey results, and it removes the mental arithmetic that so often leads to small but costly mistakes at the shop or on a spreadsheet.
Built for speed, privacy, and clarity
Every calculator on this page shares the same design goals. Calculations happen locally and instantly, the interface stays uncluttered, and the results are paired with plain language notes about what the number does and does not mean. There are no accounts to register, no inputs stored on a server, and no features hidden behind an ad wall. The aim is to give you a trustworthy number quickly, then step back so you can make the decision yourself.
Choosing the right tool
If you are comparing a loan or planning a saving goal, start with the mortgage or compound interest calculators. If you are thinking about diet or fitness, the BMI and TDEE tools are the natural fit. For quick arithmetic on discounts, tax, or shares, the percentage calculator is the one to reach for, and content creators can model a publishing business with the AdSense tool. Pick the relevant calculator below, and each page includes its own explained examples to help you interpret the result with confidence.
Private and readable
How These Tools Respect Your Privacy
Beyond the math, the way these calculators are built matters for trust. The notes below explain the privacy model and the editorial standard behind every page on this hub.
No accounts and no tracking of your inputs
Every calculator on this page runs in your own browser. The numbers you type never leave the device, no profile is built from your activity, and nothing is stored on a server that could later be matched to you. That design is not an afterthought; it is the reason the tools feel instant, because there is no network round trip between you and a result.
Written to be read, not stuffed
The explanations above are written to be read, not padded with repeated phrases to look longer. Each paragraph aims to answer a question a real visitor asks, and the examples use round numbers so you can follow the math yourself. When a topic deserves more depth, the relevant calculator page carries its own worked examples and frequently asked questions.
One hub, many tools
Keeping every calculator in a single place means you can move from a mortgage question to a BMI question without learning a new interface each time. The shared privacy model, the consistent layout, and the plain language notes are deliberate choices so the site stays easy to use as the toolkit grows. Pick any tool above and start with the numbers that matter to your decision.
What to do with the result
A calculator gives you a number; the decision is still yours. Treat each result as a starting point for a conversation with a professional, whether that is a lender, a clinician, or a financial adviser, and bring the figures you produced here so the discussion begins from something concrete rather than from guesswork. None of these tools replace qualified advice.