Free Online Calculators
Fast, accurate tools for math, finance, health, science, and more — no sign-up required.
UK Statutory Redundancy Pay Calculator
Calculate UK statutory redundancy pay using the age-banded formula from the Employment Rights Act 1996, with separate Great Britain and Northern Ireland weekly pay caps, a tax-free/taxable breakdown, and your statutory notice period.
UK Holiday Entitlement Calculator
Calculate UK statutory holiday entitlement under the Working Time Regulations 1998, pro-rated for a partial year and tracked as accrued-to-date, with an optional bank-holiday and hours-based breakdown.
UK Statutory Sick Pay (SSP) Calculator
Calculate UK Statutory Sick Pay under the post-reform rules in force from 6 April 2026, using the lower of the statutory flat rate or 80% of average weekly earnings, with no earnings threshold and no waiting days.
Germany Income Tax Calculator
Calculate your German net salary from gross pay using the official 2026 income tax tariff (§32a EStG), plus pension, health, care, and unemployment insurance, the solidarity surcharge, and church tax.
UK Salary Calculator
Calculate your UK take-home pay from gross salary using official 2026/27 PAYE income tax bands (England, Wales, Scotland, Northern Ireland), employee and employer National Insurance, workplace pension treatment, and student loan repayments.
US Income Tax Calculator
Calculate your US take-home pay from gross salary using official 2026 and 2025 IRS federal tax brackets, Social Security and Medicare (FICA) taxes, standard or itemized deductions, and pre-tax 401(k) and HSA contributions.
Body Fat Calculator
Estimate your body fat percentage using the U.S. Navy circumference method and the BMI method, with body fat category, lean mass, and ideal body fat for your age.
Waist-to-Hip Ratio Calculator
Calculate your waist-to-hip ratio (WHR) and see your cardiometabolic risk category using World Health Organization thresholds, with sex-specific bands and correct measurement guidance for men and women.
Water Intake Calculator
Calculate your personalized daily fluid target from body weight, age, exercise, climate, and pregnancy or breastfeeding status, based on NASEM Adequate Intake guidance and ACSM exercise fluid-replacement recommendations.
Protein Intake Calculator
Calculate your personalized daily protein target from body weight, age, activity level, and pregnancy or breastfeeding status, based on the IOM Recommended Dietary Allowance and the ISSN's position stand on protein and exercise.
Ideal Weight Calculator
Estimate your ideal body weight using four established medical formulas — Devine, Robinson, Miller, and Hamwi — plus the healthy weight range based on BMI, for your height and sex.
BMI Calculator
Calculate your Body Mass Index (BMI) using US, metric, or any other combination of height and weight units, with a visual gauge and healthy weight range.
Calclity brings together calculators for mathematics, finance, health and fitness, science, unit conversion, date and time, and sports in one place, so you don't need to hunt across different sites for the tool you need. Every calculator shows the exact formula and steps behind each result, not just the final number.
100% Free
Every calculator is free to use, with no sign-up, subscription, or hidden fees.
Instant Results
Calculations run right in your browser and update instantly — no waiting, no page reloads.
Step-by-Step Formulas
Every result shows the exact formula and substitution used, so you can see how the answer was calculated.
7 Languages
Use Calclity in English, German, French, Spanish, Portuguese, Italian, or Japanese — fully translated.
Why the World Needs a Smarter Way to Calculate
Every day, people type math formulas, unit conversions, and financial questions into a search bar — how much is left on a loan, how many milliliters are in three tablespoons, how fast something is moving in metric units. These aren't complicated questions, but finding a straight answer often isn't as simple as it should be.
Search for a calculator online and you'll find thousands of them. Most share the same two problems: they're buried under aggressive, layout-shifting ads that make the page harder to use than the math itself, and they treat the calculation as a black box — you type in numbers, a result appears, and you're left to simply trust it.
Calclity was built as an alternative to that standard.
Our Philosophy: Built for Clarity, Not Just Answers
A calculation is only half as useful if you don't understand the logic behind it. Whether you're a student checking a physics formula, comparing mortgage options, or converting a recipe between units, you deserve to see the reasoning, not just the number.
Every calculator on Calclity is designed around that idea: a clean, distraction-free interface, and results that show the formula and the substituted values behind them, so you can follow exactly how the answer was reached, not just read it off a screen.
A Toolset Built for Everyday Life and Advanced Work
Calclity is organized into focused categories, each covering a specific kind of problem:
Mathematics (11 tools)
From basic arithmetic and percentages to roots and scientific functions, these tools simplify equations and help students and professionals work through numbers without fighting complicated software.
Finance (19 tools)
Loan and mortgage calculators that break down interest, payments, and payoff timelines clearly, so you can see exactly where your money is going before you commit to it.
Health & Fitness (6 tools)
Baseline calculators for BMI and body composition, built to support real training, nutrition, and wellness decisions with numbers you can trust.
Unit Converters (5 tools)
Convert length and area between metric, imperial, and specialty units instantly, with exact conversion factors rather than rounded approximations.
Science (5 tools)
Physics calculators covering electricity and motion, built for students and anyone who needs a dependable reference for lab work or fieldwork.
Date & Time (2 tools)
Exact calendar math for ages, deadlines, and the span between two dates — including business-day-only counts when weekends shouldn't be part of the answer.
Sports Calculators (2 tools)
Statistics for athletes and fans, from batting average to pitching performance, calculated the way the sport actually defines them.
Architecture & Construction (4 tools)
Material quantities for building and renovation projects — concrete volumes, paint coverage, and other calculations that turn a set of dimensions into an accurate order, without over- or under-buying.
Electrical Engineering (1 tool)
Wiring checks based on electrical code rules, such as box fill, so you can choose the right size before you start the job.
Utility Without Compromise
A web calculator shouldn't force a trade-off between speed and functionality. Calclity is built mobile-first and lightweight, so every tool loads fast, runs entirely in your browser, and gives you a precise answer without the clutter.
Stop guessing at the math. Start calculating with context.