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Loan EMI Calculator Work out the fixed monthly payment (EMI) for any loan amount, interest rate and term. Finance and Loans Mortgage Calculator Estimate your monthly mortgage payment including principal, interest, tax and insurance. Real Estate Percentage Calculator Solve everyday percentage problems — find a percent, a share or a change. Mathematics Age Calculator Find an exact age in years, months and days from a date of birth. Date and Time BMI Calculator Check your Body Mass Index and weight category in metric or imperial units. Health and Nutrition Unit Converter Convert length, weight, temperature, volume, area, speed and data units instantly. Unit Converters Word Counter Count words, characters, sentences and paragraphs with live reading time. Text and Writing JSON Formatter Format, validate and minify JSON with clear error reporting. Developer Tools

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Finance and Loans Free finance and loan calculators — work out EMI, monthly payments, simple and compound interest, amortization and the true cost of borrowing. 21 tools Investment Plan your investments with free calculators for SIP, compound growth, ROI, CAGR, retirement, savings goals and long-term wealth building. 21 tools Business and Ecommerce Free business and ecommerce calculators for profit margin, markup, break-even, ROAS, CPM, conversion rate, AOV and unit pricing. 22 tools Real Estate Free real estate calculators for mortgage payments, home affordability, down payment, rent vs buy, rental yield and cap rate. 14 tools Insurance Free insurance calculators to estimate life cover, term premiums, human life value, health insurance costs and claim amounts. 5 tools Health and Nutrition Free health and nutrition calculators for BMI, daily calories, BMR, TDEE, macros, body fat, ideal weight and water intake. 17 tools Fitness Free fitness calculators for calories burned, one-rep max, running pace, TDEE, body fat and training targets — fast and private. 12 tools Mathematics Free math calculators for percentages, fractions, averages, statistics, ratios, combinations, scientific notation and more. 38 tools Education Free education calculators for GPA, grades, study time and exam scores to help students plan and track their progress. 4 tools Date and Time Free date and time tools to calculate age, durations, days between dates, business days, the day of the week and time zones. 15 tools Unit Converters Free unit converters for length, weight, temperature, speed, area, volume, power, time and currency — see every unit at once. 15 tools Text and Writing Free text tools to count words, change case, remove duplicates, find and replace, check readability and clean up your writing. 25 tools Developer Tools Free developer tools to format, minify, validate and encode — JSON, CSS, regex, base64, JWT, hashes, cron and HTML utilities. 43 tools SEO and Website Tools Free SEO and website tools to generate meta tags, Open Graph, Twitter cards, FAQ schema, robots.txt, slugs and SERP previews. 11 tools Image Tools Free image tools to compress, resize, crop, convert and extract colours — all processed privately in your browser, no uploads. 7 tools PDF and File Tools Free PDF and file tools to merge PDFs, split pages and convert documents right in your browser — private, with nothing uploaded. 5 tools Security and Privacy Free security and privacy tools to generate strong passwords and passphrases, hash text, check password strength and validate cards. 5 tools Travel and Vehicle Free travel and vehicle calculators for fuel cost, fuel economy, trip distance, speed and time, and auto loan payments. 8 tools Random Generators Free random generators — numbers, dice rolls, coin flips, name pickers, colours, passwords and UUIDs, all quick, fair and private. 7 tools Productivity Free productivity tools including a Pomodoro timer, stopwatch, countdown, QR code generator and everyday helpers to save you time. 20 tools Science and Engineering Free science and engineering calculators for Ohm's law, force, density, energy, pressure, resistor colour codes and conversions. 26 tools

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DRIP Calculator Project investment growth with dividends reinvested over time. Investment Engine Displacement Calculator Calculate engine displacement from bore, stroke and cylinder count. Travel and Vehicle Hooke's Law Calculator Solve F = k·x for spring force, spring constant or displacement. Science and Engineering HTTP Status Code Lookup Look up the meaning of any HTTP status code. Developer Tools Caesar Cipher Encode or decode text with a Caesar shift cipher, including ROT13. Text and Writing Wilks Calculator Calculate your Wilks score to compare powerlifting totals across bodyweights. Fitness Pendulum Calculator Find the period of a simple pendulum from its length, or the reverse. Science and Engineering HTML Minifier Minify HTML by removing comments and collapsing whitespace. Developer Tools

Why choose Toolzio

Privacy-first

Calculations run in your browser. Your numbers, files and text never touch a server.

Lightning fast

Lean, dependency-free code means instant results on any connection or device.

Accurate & transparent

Every tool shows its formula, method and assumptions so you can trust the result.

Works everywhere

Mobile-first, accessible and keyboard-friendly — designed for users worldwide.

Frequently asked questions

Is Toolzio free to use?

Yes. Every tool is free, with no account or registration required.

Do my inputs get stored anywhere?

No. Tools process your data locally in your browser. We do not store private calculator values, text or files.

Do the tools work on mobile?

Absolutely. Toolzio is built mobile-first with large, finger-friendly controls and works fully without a mouse.

How accurate are the results?

Each tool shows the exact formula and assumptions it uses. Financial and health tools include estimates and disclaimers.

Powerful Tools. Instant Results.