Free Online Tools & Calculators
27 free tools for finance, development, and everyday tasks. No account required, instant results in your browser.
Popular tools
Loan Repayment Calculator
Calculate monthly loan payments, total interest, and full borrowing cost for any fixed-rate loan. Works for mortgages, car loans, and more.
Currency Converter
Convert between 30 world currencies with live or manual exchange rates. Handles USD, EUR, GBP, JPY, CNY, and more.
JSON Formatter & Validator
Format, validate, and minify JSON with syntax highlighting and error detection. Runs entirely in your browser.
Password Generator
Generate strong random passwords with custom length, uppercase, lowercase, numbers, and symbols.
Unit Converter
Convert between units of length, weight, temperature, area, and speed. Results update instantly.
Percentage Calculator
Calculate percentage of a number, what percentage one value is of another, and percentage change — three calculators in one.
Finance & Math
Loan Repayment Calculator
Calculate monthly loan payments, total interest, and full borrowing cost for any fixed-rate loan. Works for mortgages, car loans, and more.
Loan Affordability Calculator
Find the maximum loan amount you can afford based on your monthly budget and interest rate.
Currency Converter
Convert between 30 world currencies with live or manual exchange rates. Handles USD, EUR, GBP, JPY, CNY, and more.
Percentage Calculator
Calculate percentage of a number, what percentage one value is of another, and percentage change — three calculators in one.
Discount Calculator
Calculate final price after a discount, the savings amount, or reverse-engineer the discount rate from two prices.
Tip Calculator & Bill Splitter
Calculate the tip amount and split the total bill equally between any number of people.
Compound Interest Calculator
See how investments grow over time with compound interest, including regular monthly contributions.
Date & Time
Date Difference Calculator
Calculate the exact number of days, weeks, and months between any two dates. Handles leap years automatically.
Age Calculator
Calculate exact age in years, months, and days from a date of birth. Shows total days lived and days until next birthday.
Time Zone Converter
Convert any date and time between 18 world time zones. Daylight saving time is handled automatically.
Developer Tools
JSON Formatter & Validator
Format, validate, and minify JSON with syntax highlighting and error detection. Runs entirely in your browser.
Base64 Encoder / Decoder
Encode text to Base64 or decode Base64 strings back to plain text. Supports Unicode, emoji, and non-Latin characters.
Color Converter — HEX, RGB, HSL
Convert colors between HEX, RGB, HSL, and HSB/HSV formats instantly. Includes a visual color picker.
URL Encoder / Decoder
Encode special characters in URLs using percent-encoding, or decode percent-encoded URLs back to readable text.
URL Shortener
Turn long URLs into short, shareable links via TinyURL, is.gd, or cleanuri — with a one-tap copy button, QR code, and local history. No sign-up required.
Regex Tester
Test regular expressions with live match highlighting. Supports flags (g, i, m) and shows capture groups.
HTML Encoder / Decoder
Convert special characters to HTML entities and decode HTML entities back to plain text.
Cron Expression Generator
Build and validate cron expressions visually with a plain-English schedule description. Copy-paste ready output.
Utilities
Password Generator
Generate strong random passwords with custom length, uppercase, lowercase, numbers, and symbols.
Word Counter & Character Count
Count words, characters, sentences, and paragraphs instantly. Includes reading time estimates.
Random Number Generator
Generate random integers or decimals within any range. Supports multiple numbers and no-duplicate mode.
BMI Calculator
Calculate your Body Mass Index (BMI) from height and weight in metric or imperial units.
Unit Converter
Convert between units of length, weight, temperature, area, and speed. Results update instantly.
Case Converter
Convert text between UPPERCASE, lowercase, Title Case, camelCase, PascalCase, snake_case, and kebab-case.
TDEE & Calorie Calculator
Calculate your Total Daily Energy Expenditure and daily calorie targets for weight loss, maintenance, or gain.
Markdown Editor & Preview
Write Markdown with a live side-by-side HTML preview. Supports full CommonMark syntax. Runs in your browser.
UUID Generator
Generate RFC 4122 UUIDs in v1, v4, or v5 format. Options for quantity, uppercase, and hyphen formatting.
What is Tools Hub, and who is it for?
Tools Hub is a free collection of calculators, converters, and lightweight utilities that run in your web browser. Whether you are comparing loan options, checking your BMI, formatting JSON for an API, or generating a UUID for a database key, you can get an answer in seconds — no account, no install. It is built for students, independent developers, small-business owners, and anyone who needs fast, dependable numbers or text transformations during a busy day.
The finance tools cover loan repayment and affordability, compound interest, tips, discounts, and currency conversion with live or manual rates. Date and time helpers handle age, time-zone conversion, and the number of days between two dates. For developers there is JSON formatting and validation, Base64 and URL encoding, cron-expression building, regex testing, and HTML encoding. Most tools run on your device, so the figures and text you type are not sent to a server just to get a result.
When a tool relies on a published formula or standard band — such as BMI categories or fixed-rate loan amortization — the assumptions are explained on that tool’s page so you can read the result in context. For legal, medical, or major financial decisions, please confirm with a qualified professional: these tools are educational and convenience aids, not a substitute for personalised advice.
Browse every tool in the categories above, or open the full tools directory to search the complete list in one place. Everything stays free, so bookmark the pages you reach for most and come back whenever you need a quick check.