500+ Free Online Tools
Calculators, converters, formatters, generators, and utilities for developers, designers, writers, students, and everyone in between. All tools run in your browser — no signup, no install, no data collection.
Popular Tools
Word Counter
Count words, characters, sentences, and paragraphs in any text.
JSON Formatter
Format, validate, and beautify JSON data with syntax highlighting.
Password Generator
Generate strong, secure random passwords with customizable options.
Mortgage Calculator
Calculate monthly mortgage payments, total interest, and amortization schedule.
Calorie Calculator
Calculate daily calorie needs based on age, weight, height, and activity level.
QR Code Generator
Generate QR codes from any text or URL for easy sharing.
Unit Converter
Convert between units of length, weight, temperature, volume, and more.
Color Converter
Convert between HEX, RGB, and HSL color formats with a live preview.
Base64 Encoder/Decoder
Encode text to Base64 or decode Base64 strings back to plain text.
Percentage Calculator
Calculate percentages, percentage change, and percentage differences.
Image Resizer
Resize images to any dimensions right in your browser.
Dice Roller
Roll virtual dice with custom sides, quantities, and modifiers.
Tool Collections
From the Blog
Color Theory for Web Design: A Practical Guide
Learn color theory fundamentals for the web — color models, harmonies, contrast ratios, accessibility, and how to build palettes that work.
Compound Interest Explained: How Your Money Grows Exponentially
Understand compound interest — the formula, how it works, why starting early matters, and how to calculate it for savings, investments, and debt.
How to Create Strong Passwords: A Science-Backed Guide
Learn what makes a password truly strong, why length beats complexity, how password managers work, and common mistakes that put your accounts at risk.
Text Tools
42Word Counter
Count words, characters, sentences, and paragraphs in any text.
Case Converter
Convert text between uppercase, lowercase, title case, sentence case, and more.
Lorem Ipsum Generator
Generate placeholder text for designs, mockups, and layouts.
Text Diff Checker
Compare two texts side-by-side and see the differences highlighted.
Slugify
Convert text to URL-friendly slugs for web addresses and file names.
Text Reverser
Reverse any text, words, or sentences instantly.
Developer Tools
62JSON Formatter
Format, validate, and beautify JSON data with syntax highlighting.
Base64 Encoder/Decoder
Encode text to Base64 or decode Base64 strings back to plain text.
URL Encoder/Decoder
Encode or decode URL components for safe use in web addresses.
HTML Entity Encoder/Decoder
Encode special characters to HTML entities or decode them back.
Regex Tester
Test regular expressions with real-time matching and group highlighting.
CSS Minifier
Minify CSS code by removing whitespace, comments, and unnecessary characters.
Math Tools
33Percentage Calculator
Calculate percentages, percentage change, and percentage differences.
Scientific Calculator
A full-featured scientific calculator with advanced math functions.
BMI Calculator
Calculate your Body Mass Index and see your health category.
Age Calculator
Calculate exact age in years, months, and days from a birthdate.
Loan Calculator
Calculate monthly payments, total interest, and amortization schedules.
Compound Interest Calculator
Calculate compound interest with customizable rates and periods.
Converters
78Unit Converter
Convert between units of length, weight, temperature, volume, and more.
Color Converter
Convert between HEX, RGB, and HSL color formats with a live preview.
Number Base Converter
Convert numbers between binary, decimal, hexadecimal, and octal bases.
Timestamp Converter
Convert Unix timestamps to human-readable dates and back.
Morse Code Translator
Convert text to Morse code and decode Morse code back to text.
Time Zone Converter
Convert times between different time zones worldwide.
Generators
40Password Generator
Generate strong, secure random passwords with customizable options.
UUID Generator
Generate universally unique identifiers (UUID v4) instantly.
QR Code Generator
Generate QR codes from any text or URL for easy sharing.
Color Palette Generator
Generate harmonious color palettes for your design projects.
Fake Data Generator
Generate fake names, emails, addresses, and more for testing.
Placeholder Image Generator
Generate placeholder images of any size with custom colors and text.
Image Tools
21Image Resizer
Resize images to any dimensions right in your browser.
Image Cropper
Crop images to custom dimensions or aspect ratios.
Image Compressor
Compress images to reduce file size while maintaining quality.
SVG to PNG Converter
Convert SVG vector images to PNG raster format.
Favicon Generator
Generate favicons in multiple sizes from any image.
Image to WebP Converter
Convert PNG, JPG, and GIF images to WebP format for smaller file sizes.
Crypto & Security
15Hash Generator
Generate MD5, SHA-1, and SHA-256 hashes from any input text.
Text Encryption/Decryption
Encrypt and decrypt text using AES encryption.
ROT13 Encoder
Encode and decode text using the ROT13 substitution cipher.
Caesar Cipher
Encrypt and decrypt text using the Caesar cipher with custom shift.
Password Strength Checker
Check how strong your password is and get improvement suggestions.
Checksum Calculator
Calculate and verify file checksums (MD5, SHA-1, SHA-256).
SEO & Marketing
15Open Graph Preview
Preview how your website looks when shared on social media.
Keyword Density Checker
Analyze keyword density and frequency in your content.
Google SERP Preview
Preview how your page will look in Google search results.
UTM Link Builder
Build UTM-tagged URLs for tracking marketing campaigns.
Email Validator
Validate email address format and check for common issues.
Twitter Card Preview
Preview how your content will look when shared on Twitter/X.
Utilities
20Pomodoro Timer
Stay focused with the Pomodoro technique — 25 min work, 5 min break.
Countdown Timer
Set a countdown timer to any date or duration.
Stopwatch
A simple stopwatch with lap tracking functionality.
Online Notepad
A simple browser-based notepad that saves to local storage.
Screen Resolution Detector
Detect your screen resolution, viewport size, and device pixel ratio.
Color Blindness Simulator
See how your designs look to people with different types of color blindness.
Finance Tools
30Mortgage Calculator
Calculate monthly mortgage payments, total interest, and amortization schedule.
Salary to Hourly Calculator
Convert annual salary to hourly rate and vice versa.
Tax Estimator
Estimate your federal income tax based on income and filing status.
Retirement Calculator
Estimate how much you need to save for retirement.
ROI Calculator
Calculate Return on Investment for any business decision or investment.
Inflation Calculator
Calculate how inflation affects purchasing power over time.
Health & Fitness
22Calorie Calculator
Calculate daily calorie needs based on age, weight, height, and activity level.
BMR Calculator
Calculate your Basal Metabolic Rate — calories burned at rest.
TDEE Calculator
Calculate Total Daily Energy Expenditure based on activity level.
Body Fat Calculator
Estimate body fat percentage using the US Navy method.
Ideal Weight Calculator
Calculate your ideal weight range based on height and frame size.
Pregnancy Due Date Calculator
Estimate your due date based on your last menstrual period.
Date & Time
22Date Difference Calculator
Calculate the exact number of days, weeks, months, and years between two dates.
Add/Subtract Days Calculator
Add or subtract days, weeks, months, or years from any date.
Days Until Calculator
Calculate how many days until a specific date or event.
Week Number Calculator
Find the ISO week number for any date and see the full week calendar.
Business Days Calculator
Calculate the number of business days (excluding weekends) between dates.
Time Duration Calculator
Calculate duration between two times and add/subtract time intervals.
Social Media
15Instagram Fonts Generator
Generate stylish fonts and special text for your Instagram bio and posts.
Hashtag Generator
Generate relevant hashtags for Instagram, TikTok, and Twitter posts.
Social Media Image Resizer
Resize images to perfect dimensions for every social media platform.
Social Character Counter
Count characters with limits for Twitter (280), Instagram (2200), and more.
YouTube Thumbnail Downloader
Download thumbnails from any YouTube video in multiple resolutions.
Twitter Thread Maker
Break long text into numbered tweet-sized threads with character counting.
PDF Tools
10PDF Merger
Merge multiple PDF files into a single PDF document.
PDF Splitter
Split PDF files into individual pages or custom page ranges.
PDF Compressor
Compress PDF files to reduce file size while keeping quality.
PDF to Image Converter
Convert PDF pages to PNG or JPG images.
Image to PDF Converter
Convert images (JPG, PNG, WebP) to a PDF document.
HTML to PDF Converter
Convert HTML content or web pages to PDF documents.
Education
20Grade Calculator
Calculate your final grade with weighted assignments and exams.
Citation Generator
Generate citations in APA, MLA, Chicago, and Harvard formats.
Flashcard Maker
Create study flashcards with flip animations saved to your browser.
Interactive Periodic Table
Browse elements with properties, electron configuration, and more.
Multiplication Table
Generate interactive multiplication tables up to any size.
Reading Speed Test
Test your reading speed in words per minute with comprehension check.
Writing Tools
25Paraphrase Tool
Rephrase text while maintaining the original meaning.
Grammar Checker
Check text for grammar, spelling, and punctuation errors.
Headline Analyzer
Analyze headlines for emotional impact, power words, and length.
Blog Title Generator
Generate catchy blog post titles from your topic or keywords.
Text Summarizer
Summarize long articles and documents into key points.
Sentence Counter
Count sentences and analyze average sentence length for readability.
Business Tools
15Invoice Maker Pro
Create professional invoices with line items, tax, and export to PDF.
Business Name Generator
Generate creative business name ideas based on your industry and keywords.
Meeting Cost Calculator
Calculate the true cost of meetings based on attendees and salaries.
QR Code Business Card
Generate a QR code vCard that saves your contact info to any phone.
Time Tracker
Track time spent on tasks and projects with start/stop and manual entry.
Profit & Loss Calculator
Create a simple P&L statement from revenue and expense entries.
Gaming & Fun
15Dice Roller
Roll virtual dice with custom sides, quantities, and modifiers.
Coin Flip
Flip a virtual coin with realistic animation and history tracking.
Random Name Picker
Pick random names or items from a list with animation.
Wheel Spinner
Spin a customizable wheel to make random decisions with flair.
Team Generator
Randomly split a group of people into balanced teams.
Online Scoreboard
Keep score for games with customizable player names and point tracking.