Built for Simplicity
Our tools are designed to be fast, intuitive, and accessible to everyone.
Lightning Fast
Get instant results with no loading screens or delays.
Privacy First
Your data stays in your browser. We never store or share your information.
Always Free
All tools are completely free to use, no hidden fees or subscriptions.
Over 70 Free Tools Across 6 Categories
From income tax calculators and BMI tools to JSON formatters and password generators, Kalcify covers the tools you need most. Available in 5 languages.
Finance & Tax
29 toolsIncome tax calculators for the US, UK, Canada, Australia, and Germany. Compound interest, loan calculators, salary tools, and VAT calculators.
Health & Wellness
7 toolsBMI calculator, calorie counter, TDEE calculator, body fat estimator, and BAC calculators based on WHO classifications.
Developer Tools
12 toolsJSON formatter, SQL formatter, password generator, DNS checker, color contrast checker, and schema validators.
Image Tools
6 toolsCompress, resize, crop, and convert images directly in your browser. Supports PNG, JPEG, WebP, and SVG formats.
Everyday Calculators
13 toolsPercentage calculator, tip calculator, discount calculator, age calculator, GPA calculator, and more everyday math tools.
Text & Document Tools
4 toolsWord counter, AI content detector, privacy policy generator, and resignation letter generator.
Start with one of our most-used calculators
Twelve calculators that cover the vast majority of everyday tax, health, finance and developer needs. Browse the full library on the tools page.
Income Tax Calculator
FinanceEstimate federal and state income tax for the 2026 tax year.
Mortgage Points Calculator
FinanceDecide whether to buy discount points based on break-even months.
Tax Bracket Calculator
FinanceFind your marginal and effective federal tax rate.
Salary Calculator
FinanceConvert hourly, weekly, monthly and annual pay across pay periods.
BMI Calculator
HealthBody Mass Index using the WHO classification with imperial and metric input.
Calorie Calculator
HealthDaily calorie needs from Mifflin-St Jeor with activity multipliers.
BAC Calculator
HealthBlood alcohol concentration with Widmark formula and US legal limits.
Age Calculator
EverydayYears, months, days, hours between two dates with timezone awareness.
Tip Calculator
EverydayTip and split a bill across any group size with tax handling.
JSON Formatter
DeveloperPretty-print, validate and minify JSON entirely in your browser.
Password Generator
DeveloperCryptographically secure passwords using the Web Crypto API.
Time Card Calculator
EverydayWeekly hours, breaks and overtime — payroll-ready totals.
Accurate Results You Can Trust
Every Kalcify tool is built with accuracy, privacy, and transparency in mind. Here is how we ensure reliable results for every calculation.
Client-Side Computation
All calculations run entirely in your browser. Your financial data, health metrics, and passwords are never sent to our servers or stored anywhere. What you enter stays on your device.
Official Data Sources
Tax calculators use rates from the IRS, HMRC, CRA, and ATO. Health tools follow WHO classifications. We cite our sources on every tool page so you can verify the data.
Available in 5 Languages
Our tools are available in English, German, French, Spanish, and Polish, with locale-specific tax rates and regulations for each country.
No Account Required
Every tool is free to use immediately. No sign-up, no email, no subscription. Just open the tool and get your result in seconds.