Free Online Tools That Just Work
131+ useful calculators, converters and everyday utilities — fast, simple and privacy-friendly.
Trending Tools
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Business & Finance
Percentage Calculator
Calculate percentages, percentage changes and reverse percentages.
Percentage Change Calculator
Calculate percentage increase, decrease and percent change between two values.
Compound Percentage Calculator
Combine multiple percentage increases and decreases and calculate the overall net change.
Profit Margin Calculator
Calculate profit, gross margin and markup from cost and selling price.
Markup Calculator
Calculate selling price and profit from cost and markup percentage.
Discount Calculator
Find sale price and savings after a percentage discount.
VAT Calculator
Add or remove VAT from a net or gross price. Get clear results instantly in a modern desktop or mobile browser.
Sales Tax Calculator
Calculate sales tax and total price from a tax rate.
GST Calculator
Add or remove GST and calculate the tax amount.
Commission Calculator
Calculate sales commission, commission rate, required sales and base-plus-commission pay.
ROI Calculator
Calculate return on investment, profit and ROI percentage.
Break-even Calculator
Estimate break-even units and break-even revenue.
Unit Price Calculator
Compare cost per unit for products or packages.
Simple Interest Calculator
Calculate simple interest, total interest and final balance from principal, rate and time.
Compound Interest Calculator
Estimate compound growth from principal, annual rate, time and compounding frequency.
Loan Payment Calculator
Estimate a fixed monthly loan payment, total payment and total interest.
Mortgage Payment Calculator
Estimate principal-and-interest mortgage payments from loan amount, rate and term.
Tip Calculator
Calculate tip amount, bill total and per-person split.
Salary to Hourly Calculator
Convert annual salary to an approximate hourly rate using work hours per week and weeks per year.
Hourly to Salary Calculator
Estimate annual, monthly and weekly pay from an hourly wage and work schedule.
CAGR Calculator
Calculate compound annual growth rate between a starting and ending value.
Savings Goal Calculator
Estimate the monthly contribution needed to reach a savings target by a chosen deadline.
Future Value Calculator
Estimate the future value of a lump sum with compound growth over time.
Debt-to-Income Ratio Calculator
Calculate monthly debt payments as a percentage of gross monthly income.
COGS Calculator
Calculate cost of goods sold from beginning inventory, purchases and ending inventory.
Inventory Turnover Calculator
Estimate inventory turnover and average days inventory is held.
Freelance Hourly Rate Calculator
Estimate a freelance hourly rate from income goals, expenses, billable hours and time off.
Price per Square Foot Calculator
Calculate price per square foot, total cost or area from any two known values.
Decimal to Fraction Calculator
Convert a decimal value to a simplified fraction with a configurable precision limit.
Fraction to Decimal Calculator
Convert a fraction or mixed number to its decimal value.
Date & Time
Day of Week Calculator
Find the weekday, day of year and ISO week number for any date.
Age Calculator
Calculate exact age in years, months and days from a birth date.
Date Difference Calculator
Find days, weeks and calendar difference between two dates.
Add or Subtract Date Calculator
Add or subtract days, weeks, months or years from a date.
Business Days Calculator
Count workdays between dates or add and subtract business days from a date.
Hours Calculator
Calculate elapsed hours and minutes between two times.
Time Duration Calculator
Calculate duration between two date-and-time values.
Week Number Calculator
Find the ISO week number for any date. Get clear results instantly in a modern desktop or mobile browser.
Birthday Calculator
Find days until the next birthday and birthday weekday.
Countdown Calculator
Calculate how much time remains until a future date.
Unix Timestamp Converter
Convert Unix timestamps to human-readable dates and back.
Time Zone Difference Calculator
Compare two UTC offsets and calculate the time difference between them.
Days Until Calculator
Count the number of days from today or a chosen start date until a future date.
Days Since Calculator
Count how many calendar days, weeks and months have passed since a date.
Month Difference Calculator
Calculate whole months, approximate months and total days between two dates.
Decimal to Time Calculator
Convert decimal hours to hours and minutes, or convert HH:MM back to decimal time.
Work Hours Calculator
Calculate worked hours between start and end times with an optional break deduction.
Developer Tools
JSON Formatter & Validator
Format, minify and validate JSON in your browser.
XML Formatter
Format, validate and minify XML online with readable indentation and browser-local processing.
HTML Formatter
Format HTML markup for easier reading. Get clear results instantly in a modern desktop or mobile browser.
CSS Formatter
Format and minify CSS for quick cleanup. Get clear results instantly in a modern desktop or mobile browser.
JavaScript Formatter
Apply lightweight formatting or minification to JavaScript code.
Base64 Encoder / Decoder
Encode text to Base64 or decode Base64 back to text.
URL Encoder / Decoder
Encode or decode URL components safely. Get clear results instantly in a modern desktop or mobile browser.
UUID Generator
Generate random RFC 4122 version 4 UUIDs locally.
Password Generator
Generate random passwords with configurable length and character sets.
Hash Generator
Generate SHA-256, SHA-384 or SHA-512 hashes in your browser.
HEX / RGB Color Converter
Convert colors between HEX and RGB formats. Get clear results instantly in a modern desktop or mobile browser.
PX / REM Converter
Convert CSS pixels and rem values using a configurable root font size.
JSON to CSV Converter
Convert a JSON array of objects into CSV text in your browser.
CSV to JSON Converter
Convert CSV text with a header row into a JSON array of objects.
HTML Entity Encoder Decoder
Encode reserved HTML characters as entities or decode entities back to text.
URL Parser
Break a URL into protocol, host, port, path, query parameters and hash.
JWT Decoder
Decode JWT header and payload sections locally without verifying the signature.
Number Base Converter
Convert integers between binary, octal, decimal and hexadecimal.
Text Binary Converter
Convert UTF-8 text to binary bytes and binary byte groups back to text.
IPv4 Subnet Calculator
Calculate network address, broadcast address, host range and usable hosts for an IPv4 CIDR block.
HTTP Status Code Lookup
Look up common HTTP response status codes and their standard meaning.
HMAC Generator
Generate HMAC signatures with SHA-256, SHA-384 or SHA-512 using the browser Web Crypto API.
URL Query Builder
Build a URL query string from a base URL and key-value parameters with correct percent encoding.
Image & PDF
Image Compressor
Compress JPG, PNG and WebP images locally in your browser.
Image Resizer
Resize an image to exact pixel dimensions in the browser.
Image Cropper
Crop an image by pixel coordinates without uploading it.
Image Format Converter
Convert images between JPG, PNG and WebP locally.
JPG / PNG Converter
Convert JPG to PNG or PNG to JPG in your browser.
QR Code Generator
Generate QR codes for URLs, text and other content.
PDF Merge
Combine multiple PDF files into one PDF in your browser.
PDF Split
Extract selected pages from a PDF into a new PDF.
Aspect Ratio Calculator
Calculate image aspect ratio and find a missing width or height while preserving proportions.
Image DPI PPI Calculator
Calculate print PPI/DPI from image pixels and physical print size.
Image to Base64 Converter
Convert an image file to a Base64 data URL locally in your browser.
Base64 to Image Converter
Preview and download an image from a Base64 data URL or raw Base64 image string locally.
Image Color Picker
Upload an image and click any point to read its HEX and RGB color locally in your browser.
PDF Organizer
Reorder, rotate and remove PDF pages with visual thumbnails.
Remove PDF Pages
Select unwanted PDF pages visually and remove them in one step.
Extract PDF Pages
Extract selected PDF pages into one PDF or separate files.
PDF to Images
Convert PDF pages to PNG or JPG images with page selection.
Images to PDF
Combine JPG, PNG or WebP images into a single PDF in your chosen order.
Image Rotate & Flip
Rotate or flip one or many images and download the results.
Image Watermark
Add text or image watermarks to multiple images with position and opacity controls.
Batch Image Renamer
Rename many image files consistently and download them together as a ZIP.
Text Tools
Words to Time Calculator
Convert word count to estimated reading and speaking time with adjustable words-per-minute rates.
Word Counter
Count words, characters, sentences and reading time instantly.
Character Counter
Count characters with and without spaces in real time.
Case Converter
Convert text to uppercase, lowercase, title case and sentence case.
Remove Duplicate Lines
Remove repeated lines while keeping the first occurrence.
Remove Empty Lines
Remove blank and whitespace-only lines from text.
Sort Lines
Sort text lines alphabetically, numerically or in reverse order.
Reverse Text
Reverse characters, words or line order. Get clear results instantly in a modern desktop or mobile browser.
Find and Replace
Find text and replace all matching occurrences in the browser.
Slug Generator
Turn a title or phrase into a clean URL slug.
Text Compare
Compare two blocks of text line by line. Get clear results instantly in a modern desktop or mobile browser.
Line Counter
Count lines, non-empty lines and characters in pasted text.
Sentence Counter
Count approximate sentences, words and characters in a block of text.
Paragraph Counter
Count paragraphs, words and characters in pasted text.
Whitespace Remover
Trim lines, collapse repeated spaces and remove unnecessary blank lines from text.
Text Repeater
Repeat a word, phrase or block of text a chosen number of times with a custom separator.
Roman Numeral Converter
Convert positive integers to Roman numerals and Roman numerals back to numbers.
Reading Time Calculator
Estimate reading time from word count and an adjustable words-per-minute speed.
Keyword Density Checker
Measure how often a word or phrase appears in text without recommending keyword stuffing.
Unit & Shipping
Length Converter
Convert length between metric and imperial units.
Weight Converter
Convert weight and mass between kilograms, pounds, ounces and more.
Area Converter
Convert area between square meters, square feet, acres and more.
Volume Converter
Convert liters, milliliters, gallons, cubic meters and more.
Temperature Converter
Convert Celsius, Fahrenheit and Kelvin. Get clear results instantly in a modern desktop or mobile browser.
Speed Converter
Convert speed between km/h, mph, m/s and knots.
Pressure Converter
Convert pressure between Pa, kPa, bar, psi and atm.
Energy Converter
Convert energy between joules, kWh, calories and BTU.
Power Converter
Convert power between watts, kilowatts and horsepower.
Data Storage Converter
Convert bytes, KB, MB, GB and TB using decimal or binary units.
CBM Calculator
Calculate cubic meters (CBM) for cartons and shipping cargo.
Volumetric Weight Calculator
Calculate dimensional weight for air and courier shipments.
Fuel Economy Converter
Convert between MPG, km/L and L/100 km fuel economy units.
Cooking Measurement Converter
Convert common volume measurements used in recipes, including cups, tablespoons, teaspoons and milliliters.
Angle Converter
Convert angles between degrees, radians, gradians and turns.
Force Converter
Convert force between newtons, kilonewtons, pound-force and kilogram-force.
Torque Converter
Convert torque between N·m, lb-ft, lb-in and kgf·m.
Frequency Converter
Convert frequency between Hz, kHz, MHz and GHz.
Data Transfer Rate Converter
Convert data rates between bit/s, Kbit/s, Mbit/s, Gbit/s and byte-based rates.
Pallet Volume Calculator
Calculate pallet cubic volume from length, width, height and quantity with unit conversion.
Flow Rate Converter
Convert common volumetric flow-rate units such as L/min, m³/h, GPM and CFM.
Helpful Guides
Compound Interest Explained: Formula, Frequency and Growth
Understand compound interest, how compounding frequency changes growth, and how to estimate a future balance.
Sep 19, 2026Simple Interest Formula: How to Calculate Interest Step by Step
Learn the simple interest formula, what each input means, and how to calculate interest and final balance with a clear example.
Sep 15, 2026Break-even Point: Units and Revenue Explained
Learn how fixed cost, selling price and variable cost determine the basic break-even point.
Sep 12, 2026How to Merge PDF Files in Your Browser
Learn how browser-based PDF merging works and what to check before combining documents.
Sep 9, 2026How to Resize an Image Without Changing Its Aspect Ratio
Learn how width, height and aspect ratio work when resizing images for websites and online forms.
Sep 6, 2026JSON Formatting and Validation Basics
Learn what valid JSON looks like, common syntax errors and when to format or minify JSON.