# CoolTool - Complete Documentation > Free online tools for developers, marketers, and everyday workflows ## About CoolTool CoolTool (https://www.cooltool.online) is a comprehensive platform offering 70+ free online tools designed to streamline your workflow. Whether you're a developer, marketer, content creator, or just need quick calculations, CoolTool provides practical solutions without signup requirements. ## Getting Started - Homepage: https://www.cooltool.online - All Tools: https://www.cooltool.online/tools - Blog: https://www.cooltool.online/blog - Contact Us: https://www.cooltool.online/contact - About: https://www.cooltool.online/about - Privacy Policy: https://www.cooltool.online/privacy-policy - Terms of Service: https://www.cooltool.online/terms-of-service --- ## CONVERTERS [Image to Text](https://www.cooltool.online/tools/image-to-text): Extract text from any image using advanced OCR technology. Upload images containing text and instantly get editable text output. Perfect for digitizing documents, receipts, screenshots, and handwritten notes. [Image Compressor](https://www.cooltool.online/tools/image-compressor): Compress images up to 80% while maintaining quality. Supports JPEG, PNG, and WEBP formats. Reduce file sizes for faster website loading and easier sharing without visible quality loss. [Image Background Remover](https://www.cooltool.online/tools/image-background-remover): Upload and prepare image background removal workflow. Remove backgrounds from product photos, portraits, and graphics to create transparent PNG files ready for design work. [Image Resizer + Batch Export](https://www.cooltool.online/tools/image-resizer-batch): Prepare multi-image resizing and batch export workflow. Resize multiple images simultaneously to specific dimensions or percentages, perfect for social media optimization or website galleries. [File Converter Hub](https://www.cooltool.online/tools/file-converter-hub): Convert image files between PNG, JPEG, and WEBP quickly. Browser-based conversion with no upload required, ensuring privacy and speed for format switching. [PDF Merge / Split / Compress](https://www.cooltool.online/tools/pdf-merge-split-compress): Upload PDFs and prepare merge, split, or compress workflows. Combine multiple PDFs into one, extract specific pages, or reduce file size for easier email sharing. [PDF to Image / Image to PDF](https://www.cooltool.online/tools/pdf-image-converter): Switch between PDF-image conversion workflows. Convert PDF pages to high-quality images or combine multiple images into a single PDF document. [JSON to CSV Converter](https://www.cooltool.online/tools/json-to-csv-converter): Convert JSON objects/arrays into CSV quickly. Transform API responses and JSON data into spreadsheet-compatible CSV format for analysis in Excel or Google Sheets. [Markdown to HTML Converter](https://www.cooltool.online/tools/markdown-to-html): Convert markdown content into HTML output instantly. Perfect for bloggers and developers who write in Markdown and need clean HTML for publishing. --- ## DEVELOPER TOOLS [JSON Formatter](https://www.cooltool.online/tools/json-formatter): Format, validate, and beautify JSON in seconds. Automatically indent and structure JSON for better readability, with error detection for invalid syntax. [SQL Formatter](https://www.cooltool.online/tools/sql-formatter): Format and beautify SQL queries for readability. Transform messy SQL into properly indented, readable code with consistent styling for database work. [JWT Decoder](https://www.cooltool.online/tools/jwt-decoder): Decode JWT header and payload locally and securely. Inspect JSON Web Tokens to view claims, expiration, and other metadata without sending data to servers. [Base64 Encoder / Decoder](https://www.cooltool.online/tools/base64-encoder-decoder): Encode and decode Base64 strings safely in-browser. Convert text or files to Base64 encoding and back, useful for embedding data and API authentication. [UUID Generator](https://www.cooltool.online/tools/uuid-generator): Generate one or multiple UUID v4 values quickly. Create universally unique identifiers for databases, APIs, and distributed systems with one click. [API Tester](https://www.cooltool.online/tools/api-tester): Test APIs in-browser with saved requests and response inspection. Make HTTP requests with custom headers, view formatted responses, and debug API endpoints without Postman. [Webhook Tester](https://www.cooltool.online/tools/webhook-tester): Send test webhook requests and inspect responses. Debug webhook integrations by sending custom payloads and viewing real-time response data. [SEO Meta Generator](https://www.cooltool.online/tools/seo-meta-generator): Generate SEO and OpenGraph meta tags ready to paste. Create optimized meta descriptions, Open Graph tags, and Twitter Cards for better search visibility and social sharing. [UTM Link Builder](https://www.cooltool.online/tools/utm-link-builder): Build campaign URLs with UTM parameters for analytics. Track marketing campaign performance by adding source, medium, campaign, and content parameters to your URLs. [CSV Cleaner](https://www.cooltool.online/tools/csv-cleaner): Clean, normalize, and deduplicate CSV lines. Remove duplicates, trim whitespace, and standardize formatting in CSV files for data analysis. [Website Screenshot Tool](https://www.cooltool.online/tools/website-screenshot-tool): Capture webpage screenshot previews from URL. Generate full-page screenshots of any website for documentation, presentations, or archiving. [Uptime Monitor](https://www.cooltool.online/tools/uptime-monitor): Run quick website uptime/availability checks. Test if your website or API endpoint is accessible and measure response time. --- ## SECURITY [Password Generator](https://www.cooltool.online/tools/password-generator): Create strong, secure passwords with custom options. Generate random passwords with configurable length, character types, and complexity requirements for maximum security. [Password Strength Checker](https://www.cooltool.online/tools/password-strength-checker): Check password strength and complexity in real-time. Evaluate password security based on length, character diversity, and common patterns to ensure account safety. [JWT Decoder](https://www.cooltool.online/tools/jwt-decoder): Decode JWT header and payload locally and securely. Inspect authentication tokens without exposing sensitive data to third-party services. [COD Guard](https://www.cooltool.online/tools/cod-guard): Check COD order risk with customer and address signals. Validate Cash on Delivery orders by analyzing customer behavior patterns and delivery address authenticity. --- ## SOCIAL MEDIA [Hashtag Generator](https://www.cooltool.online/tools/hashtag-generator): Generate trending hashtags for Instagram and TikTok. Get relevant, platform-optimized hashtags to increase post visibility and engagement based on your content topic. [Caption Generator](https://www.cooltool.online/tools/caption-generator): Create engaging captions for all social media platforms. Generate creative, attention-grabbing captions for Instagram, Facebook, Twitter, and LinkedIn posts. [Bio Generator](https://www.cooltool.online/tools/bio-generator): Write professional bios for any social platform. Create compelling profile bios optimized for Instagram, Twitter, LinkedIn, and other social networks. [LinkedIn Post Generator](https://www.cooltool.online/tools/linkedin-post-generator): Draft structured LinkedIn posts with hooks and CTA. Create professional LinkedIn content with engaging openings, valuable insights, and clear calls-to-action. [Engagement Rate Calculator](https://www.cooltool.online/tools/engagement-rate-calculator): Measure your social media performance instantly. Calculate engagement rates from likes, comments, shares, and followers to track content effectiveness. [Profile Picture Cropper](https://www.cooltool.online/tools/profile-picture-cropper): Crop profile pictures to perfect platform dimensions. Resize and crop images to meet exact specifications for Instagram, Twitter, LinkedIn, and Facebook profile photos. --- ## TEXT TOOLS [Word Counter](https://www.cooltool.online/tools/word-counter): Count words, characters, and estimate reading time. Analyze text for word count, character count, sentence count, and reading time estimates for content optimization. --- ## UTILITIES [QR Code Generator](https://www.cooltool.online/tools/qr-code-generator): Create custom QR codes with colors and multiple formats. Generate QR codes for URLs, text, contact info with customizable colors and download as PNG or SVG. [QR Menu Generator](https://www.cooltool.online/tools/qr-menu-generator): Generate menu QR codes for restaurants and cafes. Create scannable QR codes that link to digital menus for contactless dining experiences. [Timezone Converter](https://www.cooltool.online/tools/timezone-converter): Convert times across multiple timezones with meeting scheduler. Schedule international meetings by comparing times across different time zones simultaneously. [Currency Converter](https://www.cooltool.online/tools/currency-converter): Convert currency values with live-rate support and fallback. Get real-time exchange rates for 150+ currencies for accurate international transaction calculations. [Crypto Converter](https://www.cooltool.online/tools/crypto-converter): Convert crypto to crypto, crypto to fiat, and fiat to crypto. Real-time cryptocurrency conversion supporting Bitcoin, Ethereum, and 100+ altcoins. [Unit Converter](https://www.cooltool.online/tools/unit-converter): Convert length, weight, and temperature units instantly. Switch between metric and imperial units for distance, mass, and temperature measurements. [Percentage Calculator](https://www.cooltool.online/tools/percentage-calculator): Solve common percentage calculations and growth rate. Calculate percentages, percentage increases/decreases, and find what percentage one number is of another. [BMI Calculator](https://www.cooltool.online/tools/bmi-calculator): Calculate your body mass index and healthy weight range instantly. Determine BMI category and get personalized healthy weight recommendations. [Age Calculator](https://www.cooltool.online/tools/age-calculator): Calculate exact age in years, months, and days with birthday countdown. Find precise age differences and days until next birthday. [Loan EMI Calculator](https://www.cooltool.online/tools/loan-emi-calculator): Calculate monthly EMI, total payment, and loan interest. Plan loan repayments by calculating Equated Monthly Installments for home, car, and personal loans. [GST / VAT Calculator](https://www.cooltool.online/tools/gst-vat-calculator): Add or remove GST/VAT and calculate exact tax totals. Compute tax amounts for invoicing and pricing with support for various tax rates. [What is My IP](https://www.cooltool.online/tools/what-is-my-ip): Find your public IP address and location information instantly. Display your current IP address, ISP, and approximate geographic location. [Internet Speed Check](https://www.cooltool.online/tools/internet-speed-check): Measure ping, download speed, and upload speed in one click. Test your internet connection performance with accurate bandwidth measurements. [Prayer Times](https://www.cooltool.online/tools/prayer-times): Get accurate daily prayer times for any city with method options. Find precise Islamic prayer times (Fajr, Dhuhr, Asr, Maghrib, Isha) for your location. [Islamic Date Today](https://www.cooltool.online/tools/islamic-date-today): Find today's Hijri date instantly with localized weekday details. Convert Gregorian dates to Islamic Hijri calendar dates. [Ramadan Calendar](https://www.cooltool.online/tools/ramadan-calendar): Generate a full Ramadan calendar with suhoor and iftar times. Get complete month-long prayer and fasting schedules for Ramadan. [Color Palette Generator](https://www.cooltool.online/tools/color-palette-generator): Generate clean color palette combinations instantly. Create harmonious color schemes for design projects with hex codes and preview. [Favicon Generator](https://www.cooltool.online/tools/favicon-generator): Create a simple favicon PNG from text and color. Generate website favicons quickly with customizable text, background color, and text color. [Domain Name Generator](https://www.cooltool.online/tools/domain-name-generator): Get brandable domain name ideas from keywords. Generate creative, memorable domain name suggestions for your business or project. --- ## PRODUCTIVITY [CV Builder](https://www.cooltool.online/tools/cv-builder): Create a professional CV with drag-and-drop sections and export to PDF. Build comprehensive resumes with customizable sections, formatting, and instant PDF download. [Resume Bullet Rewriter](https://www.cooltool.online/tools/resume-bullet-rewriter): Rewrite plain resume bullets into stronger achievement lines. Transform basic job descriptions into compelling achievement-focused resume bullets. [Invoice Generator](https://www.cooltool.online/tools/invoice-generator): Generate simple client invoices and export as PDF. Create professional invoices with itemized services, tax calculations, and payment terms. [Simple Contract Generator](https://www.cooltool.online/tools/simple-contract-generator): Create a basic service contract draft in seconds. Generate simple service agreements with customizable terms for freelance work. [Meeting Minutes Summarizer](https://www.cooltool.online/tools/meeting-minutes-summarizer): Summarize long meeting notes into key actions and decisions. Transform verbose meeting notes into concise action items and key takeaways. [Email Subject Line Generator](https://www.cooltool.online/tools/email-subject-line-generator): Generate professional subject lines with better clarity. Create compelling email subject lines that improve open rates and communication effectiveness. [AI Prompt Optimizer](https://www.cooltool.online/tools/ai-prompt-optimizer): Turn rough prompts into cleaner, higher-quality AI prompts. Refine and improve prompts for ChatGPT, Claude, and other AI models for better results. [Calorie Needs Calculator](https://www.cooltool.online/tools/calorie-needs-calculator): Estimate daily maintenance calories from profile and activity. Calculate Total Daily Energy Expenditure (TDEE) based on age, weight, height, and activity level. [TDEE / Macro Calculator](https://www.cooltool.online/tools/tdee-macro-calculator): Get calorie target plus protein, carbs, and fats split. Calculate macronutrient distribution for muscle gain, fat loss, or maintenance goals. [Body Fat Calculator](https://www.cooltool.online/tools/body-fat-calculator): Estimate body fat percentage with tape measurements. Calculate body composition using the U.S. Navy method with simple measurements. [Water Intake Calculator](https://www.cooltool.online/tools/water-intake-calculator): Estimate daily hydration target based on weight and activity. Determine optimal daily water consumption for health and performance. --- ## Tool Categories [Converters](https://www.cooltool.online/tools/category/converters): Image, PDF, and file format swaps in seconds. All conversion tools in one place for seamless file format transformations. [Developer Tools](https://www.cooltool.online/tools/category/developer-tools): JSON, SQL, JWT, and testing utilities. Essential tools for developers including formatters, decoders, and API testing. [Security](https://www.cooltool.online/tools/category/security): Strong passwords and quick risk checks. Security-focused tools for password management and risk assessment. [Social Media](https://www.cooltool.online/tools/category/social-media): Captions, hashtags, bios, and posts. Complete toolkit for social media content creation and optimization. [Text Tools](https://www.cooltool.online/tools/category/text-tools): Word counts and text readiness checks. Analyze and process text content efficiently. [Utilities](https://www.cooltool.online/tools/category/utilities): Everyday calculators and quick checks. Essential everyday tools for calculations and conversions. [Productivity](https://www.cooltool.online/tools/category/productivity): Summaries, invoices, and documents. Boost productivity with document generators and content optimizers. --- ## Support & Resources [Contact Support](https://www.cooltool.online/contact): Get help with any tool or feature, report bugs, or suggest new tools. Our team responds to all inquiries. [Blog](https://www.cooltool.online/blog): Read guides, tutorials, and tips on using various tools effectively. Learn best practices and discover new features. [About CoolTool](https://www.cooltool.online/about): Learn about our mission to provide free, accessible tools for everyone. Discover our commitment to privacy and user experience. [Privacy Policy](https://www.cooltool.online/privacy-policy): Understand how we handle your data. We prioritize user privacy with client-side processing wherever possible. [Terms of Service](https://www.cooltool.online/terms-of-service): Review our terms of service and usage guidelines for all CoolTool platforms and services. --- ## Technical Information All tools are designed with privacy in mind. Most processing happens client-side in your browser, meaning your data never leaves your device. Tools are optimized for speed and ease of use, with no signup required for basic functionality. For developers: All tools are built with modern web technologies including Next.js, React, and TypeScript. Tools are mobile-responsive and work across all modern browsers. --- Last Updated: 2025-04-25 Website: https://www.cooltool.online