Stopwatch
Precise timing, record time points, support full-screen mode and data export
Free online tool library for all major online tools: text, image, video, math, and more.
Precise timing, record time points, support full-screen mode and data export
Analog clock with automatic settings, can simulate examination room clock
Real-time display of current time, support page flipping and multiple themes
Custom target time with real-time countdown reminders
Real-time view of time zones around the world
Precisely calculate sunrise/sunset blue hour times for photography - supports any global location
Professional date time calculator supporting date offset, timestamp offset, interval calculation, and arithmetic with parentheses. Two-way date/timestamp input with one-click copy.
Free online Pomodoro timer with task list and break management. Boost your productivity with this web-based focus timer - perfect for study, work, and time management. Features custom work/break durations, todo list, and pomodoro counter.
Free online alphabetical sort tool that arranges words, names and lists in ascending or descending order. Supports deduplication, case-insensitive sorting, auto-numbering and custom separators for efficient text sorting.
Free online alphabetize tool and list sorter to arrange any text in alphabetical order instantly. Sort names, references, vocabulary, or code with A to Z and Z to A modes. Advanced options include ignore case, remove duplicates, reverse order, and trim whitespace for efficient text sorting.
Free online APA citation generator to create APA 7th edition references and in-text citations instantly. Generate citations for websites, books, journal articles, news, and videos. Get accurate reference entries with one-click copy for academic writing, essays, and research papers.
Free online article word counter to count Chinese characters, English words, characters, paragraphs, and sentences in real time. Instantly analyze mixed Chinese-English text with accurate word count and character count for essays, articles, and SEO content. No registration required, all processing happens in your browser.
Free online ASCII art generator to convert text and images into ASCII character art instantly. Supports multiple classic font styles, custom character set density, and brightness adjustment for detailed and artistic output. Perfect for terminal welcome screens, code comment decoration, and retro creative design. Copy and share in one click, no registration required, all processing happens in your browser.
Free online ASCII art generator to convert plain text into ASCII art instantly. Supports standard, bold, fancy, inverted, double-line, script, gothic, and tiny font styles, with plain ASCII, bordered, and colorful terminal output styles. Perfect for social media signatures, forum posts, code comments, and poster design. Copy and share in one click, no registration required, all processing happens in your browser.
Free online ASCII banner generator to convert plain text into ASCII art instantly. Built-in multiple classic ASCII font styles and fill characters, with real-time preview of ASCII large banners and one-click copy of text-to-ASCII results. Perfect for code comment headers, terminal welcome slogans, and social media signatures. Each character occupies 6 columns by 7 rows, best kept within 10 characters. No registration required, all processing happens locally in your browser.
Online conversion of text to SVG
Supports online preview and conversion of Heic to other image formats
Convert JFIF to other image formats
Convert ICO to other image formats
Convert avif format to other image formats
Add text or image watermark to photos online
Generate iOS, Android and Web icons in all sizes from one image
Based on Canvas rendering, enter comma-separated Y values to automatically generate stacked or overlap area charts. Supports gradient fill and one-click PNG export for data visualization.
Online audio compression with adjustable bitrate and sample rate
Online audio format conversion between MP3, WAV, OGG, AAC with lossless WAV output
Online audio crossfade tool that smoothly transitions and joins two audio clips with linear, equal-power, and S-curve fade options, adjustable crossfade duration, and lossless WAV output
Online audio cutter that trims audio files by start and end time with preview and lossless WAV output, supporting MP3, WAV, OGG, M4A, and FLAC for ringtone making and podcast editing
Online audio echo effect tool that adds delay echo to audio files with single, multi, and ping-pong echo modes, adjustable delay time, feedback, and echo count, supporting local Web Audio API processing and lossless WAV output for music production and sound design
Online audio EQ presets tool that applies professional equalizer presets like rock, pop, jazz, classical, electronic, vocal boost, bass boost, speech and telephone to audio files, with 10-band gain fine-tuning, real-time preview and lossless WAV output using local Web Audio API BiquadFilter processing for music production and audio quality optimization
Online audio equalizer tool that adjusts audio frequency with a 10-band graphic equalizer covering 32Hz to 16kHz, letting users tune low, mid and high frequency gain from -12dB to +12dB, switch built-in presets like rock, pop, jazz, classical, vocal, bass boost and treble boost, preview changes in real time and download lossless WAV output, all processed locally with the Web Audio API BiquadFilter for music production and audio quality optimization
Online audio fade in out tool that adds professional audio gradient effects to audio files, letting users customize fade in duration and fade out duration from 0 to 10 seconds, choose from four curve types including linear, logarithmic, S curve and exponential, preview audio fade in out effects in real time, and download lossless WAV output, all processed locally with the Web Audio API GainNode for podcast production, music creation and video scoring without uploading files to any server
Free online percentage calculator. Calculate percentages, find percent of numbers, percentage change, and convert between percent, fraction, and decimal.
Calculate variance and standard deviation
Precise calculation in fraction form
Calculate the nth power of any number
Calculate square root/cube root/nth root
Calculate logarithm values with any base
Calculate growth rate and rate of change online
Calculate the percentage difference between two values
Free online acceleration unit converter, supporting m/s², Gal, g, ft/s² and more
Free online acre to square meter converter, supporting bidirectional conversion between acres and square meters with real-time calculation
Free online angle conversion calculator, supporting bidirectional conversion between degrees, radians and gradians with real-time calculation and common angle reference table
Free online angle unit converter supporting mutual conversion between degrees, radians, gradians, arcminutes, arcseconds and turns with real-time calculation and intermediate calculation steps, suitable for math learning, engineering measurement and trigonometric calculation scenarios
Free online area unit converter supporting mutual conversion between square meters, square kilometers, hectares, mu, square feet, square yards, acres and 30+ other area units with real-time calculation and instant results for all units, suitable for real estate measurement, land planning and construction engineering scenarios
Free online aspect ratio calculator that simplifies width and height into the simplest integer ratio and reverse-calculates one side from a known ratio and dimension, with built-in 16:9, 4:3, 21:9, 1:1 presets and common resolution references for responsive layouts, video editing and multi-platform export
Free 1RM calculator to estimate your one rep max for squat, bench press, deadlift, overhead press, and barbell row. Uses Epley, Brzycki, Lombardi, and O'Conner formulas to generate training load charts. Plan your strength training with science-based percentage tables.
Calculate body surface area by inputting height and weight
Calculate Body Mass Index
Calculate Basal Metabolic Rate
Calculate body fat percentage
Calculate standard body weight
Convert HbA1c percentage to estimated average glucose with unit switching support
Calculate APRI score for non-invasive liver fibrosis assessment using AST and platelet count
Calculate MD5 value of files/strings
Mutual conversion between strings/files and Base64
Generate RSA keys and perform encryption/decryption
Calculate and verify CRC32 checksum
JWT decryption/verification/generation
Free leetspeak translator to convert normal text to 1337 hacker style and back. Supports basic, intermediate, and advanced leet speak modes with real-time preview. Generate unique gaming usernames, enhance passwords, or create stylish social media text with our leet text generator.
AES-256-GCM encryption and decryption with password protection
Atbash cipher encryption and decryption by reversing the alphabet A-Z to Z-A
Convert binary code to text, decimal, hex, and octal. Free online binary translator with real-time conversion.
Generate Apache httpd.conf with VirtualHost, reverse proxy, SSL certificate, and RewriteRule. Free online Apache config generator for web server deployment.
Generate WCAG-compliant ARIA labels with role, aria-label, and aria-describedby attributes. Free online ARIA label generator for accessible web development and screen reader support.
Free online Armstrong number checker to verify if a number is an Armstrong number (narcissistic number). Supports batch range search for all Armstrong numbers and shows step-by-step digit power calculation. Essential tool for math enthusiasts and programming learners to test narcissistic number logic.
Free online ASCII converter for real-time bidirectional conversion between text and ASCII decimal, hexadecimal, and binary codes. Supports ASCII code table lookup, batch text conversion, uppercase hex toggle, and one-click copy of all results. Essential tool for programmers debugging encoding, computer network learning, and character encoding education, runs entirely in browser with no registration required.
Free online ASCII table query tool showing all 128 standard ASCII characters with decimal, hexadecimal, octal and binary codes. Supports filtering control characters and printable characters, one-click copy of any ASCII encoding. Perfect for serial port debugging, text file format conversion, HTML entity encoding and computer science basics learning. No registration required, pure front-end local processing.
Free online ASCII to Hex converter supporting bidirectional conversion between text and hexadecimal. Real-time ASCII to hex conversion and hex to ASCII decoding, with batch conversion and one-click copy of results. Perfect for programmer debugging, network protocol analysis, binary file inspection and character encoding learning. Supports standard ASCII character set (0-127) including letters, digits and punctuation. Pure front-end local processing, no registration required.
Free online Ascii85 encoder and decoder supporting bidirectional conversion between binary data and Ascii85 (Base85) text. Real-time Ascii85 encoding and decoding with Adobe and standard Z85 variants, drag-and-drop file upload, batch processing and one-click copy. Perfect for PostScript and PDF binary stream handling, Git binary patch analysis, and data transmission efficiency optimization. Pure front-end local processing, no registration required.
Calculate IPv6 subnet information with 128-bit addressing and modern network prefix notation
Design VLSM networks with drag-and-drop planning and optimal space allocation
Design efficient subnets with Variable Length Subnet Masking for optimal address space utilization
Aggregate multiple networks into a single supernet for route summarization and efficient routing table management
Calculate IPv4 subnet information instantly with CIDR support. Get network address, broadcast address, subnet mask, wildcard mask, and usable host count
Free 401k calculator to estimate your 401k contribution amount, employer match, and future retirement balance. Compare Traditional vs Roth 401k, check contribution limits, and plan your retirement savings strategy with compound growth projections.
Free 401k growth calculator to project your retirement balance with compound interest. Estimate employer match contributions, check 401k annual limits, and compare Traditional vs Roth 401k. Get year-by-year breakdown and 4% safe withdrawal rate for retirement planning.
Free 401k employer match calculator to estimate your employer match amount, total annual contribution, and retirement balance. Check 401k contribution limits, compare Traditional vs Roth 401k, and maximize your employer match benefits with compound growth projections.
Free 401k retirement calculator to estimate your 401k balance at retirement. Input salary, contribution rate, and employer match to project total savings with compound interest, tax savings, and annual contribution limits. Generate yearly growth charts for informed retirement planning.
Free 529 college savings calculator to estimate future education costs and plan your 529 contributions. Account for college tuition inflation, compound interest growth, and monthly savings to determine if you're on track. Includes 529 account earnings calculation and funding gap analysis.
Free 529 plan calculator to estimate your education fund growth with tax-free compound interest. Compare account balance against projected college costs, calculate coverage rate, and identify funding gaps. Adjust contribution strategies to achieve your college savings goals.
Free CFM calculator and air flow calculator for HVAC duct sizing. Calculate cubic feet per minute from duct diameter and air velocity, or find duct size from target CFM. Includes air changes per hour and cooling load estimate.
Free airport code lookup tool with a database of 200+ global airports. Search by IATA 3 letter code, city name, or airport name to find airport details. Includes airport code list by continent and common airport codes reference table.
IToolLib is a free, open, and instantly accessible online tool library designed to bring together the most practical utilities for everyday work and study. Whether you are a student, developer, designer, content creator, or office worker, you will find tools here that help you complete tasks faster without the need to download software or create an account. The core philosophy of IToolLib is simplicity, speed, and privacy — every tool is carefully selected to be functional, intuitive, and ready to use in your browser.
The library is organized into eight major categories: Text Tools, Image Tools, Video Tools, Math Tools, Health Tools, Encoding Tools, Developer Tools, and Network Tools. Within each category, multiple sub‑tools are available, totaling over a hundred utilities. Each category page highlights the newest or recently updated tools so you can discover additions without browsing through long menus. Every tool card also includes a brief description to help you understand its purpose before opening it.
Text Tools are among the most frequently used on IToolLib. They include text formatters, case converters, word counters, character counters, diff checkers, regex replacements, random text generators, and Base64 encoding/decoding in text mode. For example, the diff checker lets you quickly compare two pieces of text to find differences, while the case converter switches between title case, uppercase, and lowercase with one click. All text processing happens locally in your browser, so your content never leaves your device.
The Image Tools category covers everything from basic edits to more advanced processing. You can resize images to specific dimensions, compress them to reduce file size for sharing or uploading, convert between formats like PNG, JPG, and WebP, and even remove backgrounds with a single click. These tools support common image formats and offer simple parameter adjustments. Batch processing is available in some tools, which is ideal for handling multiple images at once.
Video Tools provide lightweight video processing solutions. You can trim clips, merge multiple videos into one, convert formats (e.g., MP4, WebM, GIF), and compress video files to save space. All processing runs either in the browser or on a lightweight server, and no professional software is required. For simple video editing needs, IToolLib’s video tools are more than capable and have an extremely low learning curve.
Math Tools include a variety of calculators, from basic arithmetic to advanced problem solving. Common examples are percentage calculators, unit converters (length, weight, temperature, area, etc.), equation solvers, scientific calculators, fraction calculators, and date calculators. These tools are perfect for students doing homework, engineers making quick estimates, or financial professionals calculating percentages. All calculations are displayed in real time with precise results and are optimized for mobile touch screens.
Health Tools offer calculations and lookups related to everyday wellness. The BMI calculator helps you determine if your weight is within a healthy range, the calorie estimator approximates energy expenditure based on activity type and duration, the heart rate zone finder helps athletes determine optimal training intensity, and the water intake calculator recommends daily hydration based on weight and activity level. These tools are based on accepted medical formulas and guidelines; results are for reference only and do not replace professional medical advice.
Encoding Tools and Developer Tools are professional categories for programmers and technical enthusiasts. Encoding tools include Base64 encoding/decoding, URL encoding/decoding, hash calculators (MD5, SHA-1, SHA-256), JSON formatting and validation, and HTML entity conversion. Developer tools provide a regex tester, code minifier (JS/CSS/HTML), color picker and converter, timestamp converter, UUID generator, and QR code generator. These tools have clean interfaces and respond quickly, making them essential for daily debugging and development.
Network Tools help you diagnose and understand network conditions. You can use the IP lookup to see your current public IP address and location, DNS check to query domain resolution records, speed test to measure download and upload speeds, and also port scanner and Whois lookup tools. These are valuable for network administrators, webmasters, and ordinary users troubleshooting connectivity issues. All network tools operate over secure HTTPS connections to ensure data safety.
Privacy and data security are top priorities for IToolLib. The vast majority of tools run entirely in the browser; your files, text, and input never leave your device and are never uploaded to any server. A few tools that require server-side conversion (such as video format conversion) are clearly labeled and use encrypted transmission with automatic deletion, ensuring your data is not stored or misused. IToolLib does not track user behavior or display intrusive ads, providing a clean, secure, and efficient environment.
The interface is fully responsive, offering a consistent experience on desktops, tablets, and phones. Every tool is adapted for mobile use with touch-friendly buttons and input areas. IToolLib is regularly updated based on user feedback, and you can submit suggestions through the contact options at the bottom of the page or via the GitHub repository. Our goal is to make IToolLib an indispensable online toolbox for your daily work.
No registration is required. Every tool in the free online tool library is available instantly—just open the category, choose a tool, and start working. There are no sign-up forms, email verifications, or hidden paywalls. The library focuses on fast, frictionless access so you can complete tasks without account setup.
Yes, most tools in this free online tool library process your input entirely in the browser. Files and text never leave your device, meaning no server uploads or third-party tracking. This local processing keeps sensitive content private and secure. Only a few tools with server-side conversion may temporarily transfer data, and those cases are clearly indicated within the tool interface.
Absolutely. The free online tool library uses responsive design so every tool adapts to mobile, tablet, and desktop screens. Buttons, input areas, and result panels reflow automatically for touch interaction. You can use the same tools on your phone or laptop without losing functionality, making the library convenient for on-the-go tasks.
We welcome feedback through the contact options at the bottom of the page or by opening an issue on GitHub. The development team reviews suggestions regularly and updates tools based on user input. Sharing your experience helps improve the free online tool library and ensures the tool collection stays relevant and useful.
Explore all tools now and find the perfect online solution for your needs.
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