Finance, health, math, time and developer tools, all free with no signup. Tax and benefit figures follow official 2026 data.
Tax and paycheck calculators use the official 2026 IRS figures: tax brackets, standard deductions, and Social Security and Medicare rates. Health calculators use published formulas and CDC, NIH and WHO definitions, and each page names its sources. Results are estimates based on what you enter, so check with a professional before a big decision.
No account required for any tool on this site. Open any calculator, enter your numbers, get your answer. No email, no password, no credit card, ever.
Use our Paycheck Calculator under Finance. Enter your salary or hourly rate, select your filing status and state, and instantly see your take-home pay after federal taxes, Social Security, Medicare, and state taxes.
The World Clock widget on this page shows your current local time automatically. For other cities, visit our Time Zone Converter to compare times across any two locations instantly.
Tax figures are updated when the IRS publishes the next year's inflation adjustments, usually in the fall, and again whenever a law or agency changes a figure during the year. Each calculator page shows its Last updated date. Math formulas do not change, and health tools are reviewed when the CDC, NIH or WHO revise their guidance.
The numbers you type into a calculator are processed in your browser and are not sent to us. There are no accounts and no database of inputs. A few tools contact an outside service to work: the currency converter loads exchange rates, the What Is My IP tool queries an IP location service, and This Day in History loads events from Wikipedia. The privacy policy lists each one.
Use our Percentage Calculator under Math. It handles three common scenarios: what is X% of Y, X is what percent of Y, and percentage change from X to Y. All instantly and free.
The How Much House Can I Afford calculator estimates your maximum home price from gross income, monthly debts, down payment and interest rate. A common lender guideline is the 28/36 rule: housing costs at or below 28% of gross monthly income and all debt payments at or below 36%.
Yes. Our Temperature Converter converts between Celsius, Fahrenheit, Kelvin and Rankine instantly. The formula is F = (C × 9/5) + 32. You can also convert any unit of length, weight, speed, area, volume and data storage in our Converters section.
Go to our Free QR Code Generator under Dev Tools. Enter any URL, text or contact info, choose your size and color, and download the QR code as a PNG. No signup, no watermark, completely free.
Our Calendar Converter shows any date in 11 calendar systems at once: Gregorian, Julian, Islamic (Hijri, tabular and Umm al-Qura), Hebrew, Persian, Ethiopian, Coptic, Byzantine, Roman AUC and the Maya Long Count. Find it under Converters.
Our Random Number Generator under Fun uses JavaScript's Math.random() to generate uniformly distributed numbers in any range you specify. You can generate multiple numbers at once, allow or forbid duplicates, and sort the results.
Yes. Our Coin Flip tool gives you an animated heads-or-tails result with streak tracking. Our Dice Roller supports D4, D6, D8, D10, D12, D20, D100 and custom-sided dice, handy for D&D and tabletop RPGs. Both are under Fun → Randomizers.
Use our BMI Calculator under Health. Enter your height and weight in metric or imperial units. BMI = weight (kg) / height (m)². Underweight: below 18.5. Healthy weight: 18.5 to 24.9. Overweight: 25 to 29.9. Obesity: 30 and above. Note: BMI does not account for muscle mass or body composition.
Gross pay is your salary or wages before any deductions. Net pay (take-home pay) is what remains after federal income tax, Social Security (6.2% on wages up to $184,500 in 2026), Medicare (1.45%), state income tax, and any pre-tax deductions like 401(k) or health insurance. Our Paycheck Calculator shows you the full breakdown.
Use our JSON Formatter under Dev Tools. Paste any JSON string and it instantly formats it with proper indentation, validates the syntax, and highlights errors. You can also minify JSON to remove all whitespace. Useful for APIs, config files, and debugging.
Our Compound Interest Calculator uses the formula A = P(1 + r/n)^(nt) where P = principal, r = annual rate, n = compounds per year, t = years. For example, $10,000 at 7% compounded monthly for 20 years grows to $40,387. Time matters far more than compounding frequency: the same deposit compounded once a year still reaches $38,697.
Yes. Our Age Calculator shows your exact age in years, months, days, hours, minutes and seconds. Our Seconds Alive Calculator under Fun shows the total seconds you have been alive with a live counter. Our Days Between Dates calculator computes the exact difference between any two dates.
Our Currency Converter supports 30 currencies: the euro plus the 29 currencies the European Central Bank publishes reference rates for, including USD, GBP, JPY, CHF, CAD, AUD, CNY, INR, MXN and BRL. The ECB sets these rates once each business day at about 16:00 CET, and the converter loads the latest set through the free Frankfurter service. They are reference rates, not the rate a bank or card will charge you.
Not on this homepage. Tool pages have a few ad slots, each clearly labeled. Until Google AdSense approves the site, those slots show ads for other sites run by the same owner (LegalCost.us, discount5.us and favorit5.us), marked Our network. Ads never change what a calculator returns.
Currently, CalculatorsHub is in English only, targeting US and anglophone markets. The calculators use US units and US tax data by default. Most converters work globally. All tools work in any modern browser regardless of your device language setting.
Yes. Every calculator and converter works in any modern mobile browser, with layouts built for small screens, and nothing needs to be installed. You can add a page to your home screen from the browser menu to open it like an app. Your inputs stay on your device, so it works the same on a phone, tablet or computer.
CalculatorsHub is a free collection of 172 calculators, converters and generators in eight categories, written for US users: US tax rules, US units first, dollar amounts. Every tool runs in your browser with no account, and every tool page shows its sources and a Last updated date.
Most calculator sites are built once and forgotten. Here, tax brackets, benefit amounts, loan limits and conversion factors are checked against the agencies and standards that publish them, and a page is re-dated whenever one of its figures changes.
The tools here also go deeper than single-number outputs. The mortgage calculator gives you a full amortization schedule and total cost breakdown. The paycheck calculator covers federal income tax, Social Security, Medicare and a state income tax estimate. The BMI calculator shows the adult categories used by the CDC and WHO. The currency converter uses the European Central Bank's daily reference rates. The budget calculator has a 50/30/20 rule analyzer and savings goal tracker built in.
No account required. No paywalls. No ads that block the tool, and none at all on this homepage. Every calculator is free, works on any device, and gives you results in seconds.
Each tool page ends with a short Method and sources note naming the formula and the official sources behind it, and shows a Last updated line with the date its figures were last checked. Tax figures are refreshed when the IRS publishes the next year's numbers, usually in the fall, and again when a law or agency changes a figure during the year.
| Category | Tools | Figures and formulas come from |
|---|---|---|
| Finance & Tax | 41 | IRS, SSA, CMS (Medicare), FHFA and Freddie Mac (loans), BLS (inflation) |
| Health & Fitness | 24 | CDC, NIH, WHO and the published formulas each tool names (for example Mifflin-St Jeor) |
| Math | 25 | Standard formulas; no yearly figures involved |
| Time & Date | 18 | Your browser's built-in time zone database (IANA); Wikipedia for This Day in History |
| Dev Tools | 21 | The published standards for each format (JSON, Base64, UUID, hashes, cron) |
| Fun | 30 | Published averages and NASA planet data where numbers are involved; results are for fun |
| Converters | 12 | Exact NIST conversion factors; European Central Bank reference rates for currency |
That is 171 tool pages. Two tools sit in eight categories each (the Unix timestamp converter in Time and Dev Tools, and What If I Invested in Finance and Fun), so there are 172 distinct tools.
A calculator applies a published formula to the numbers you give it. It cannot see the rest of your situation: other income, credits you qualify for, your lender's rules, your employer's plan or your medical history. Use the results to plan, compare and check your own math, then confirm anything important with the IRS, your lender, your plan administrator or your doctor. The disclaimer covers financial, tax and health estimates in more detail.
Suggest a new calculator, report an issue, or ask about advertising on CalculatorsHub. We read every message.