Free Online Tools - Developer & Utility Tools
54 browser tools for text, data, images and development. No signup. Most calculations run locally; external lookups need a connection.
Compare CSV Files by Key: Added, Removed, Changed
Compare two CSV files by unique keys, even with reordered rows. Review added, removed and changed records, then export a full JSON audit or differences CSV.
CSV Duplicate Remover: Compare Selected Columns
Remove duplicate CSV records by selected columns. Keep first or last, preview decisions, preserve text IDs, and export kept and removed records separately.
Desk Fit Checker: Clamp and Room Dimensions
Check desk thickness, clamp contact areas, rail clearance and room space. See dimension conflicts and unknowns, then download or print a geometry plan.
Age Calculator - Exact Age in Years, Months, Days
Free age calculator. Find your exact age in years, months, and days from your date of birth, plus total days lived, day of the week you were born, and a countdown to your next birthday.
BMI Calculator - Body Mass Index with Healthy Weight Range
Free BMI calculator for metric and imperial units. Get your body mass index, weight category, and the healthy weight range for your height — instantly, in your browser.
Rough LLM Token & Cost Estimator
Estimate a rough token budget from text and calculate costs with your own input and output USD rates. A planning heuristic, not a provider token count.
Countdown Timer
Free online countdown timer. Set a target date and watch a live countdown in days, hours, minutes, and seconds. Quick-set buttons for common events.
CSS Minifier
Free CSS minifier tool. Paste your CSS and instantly get a minified version with size reduction stats. Runs entirely in your browser, no data uploaded.
HTML Minifier
Free HTML minifier tool. Paste HTML and get a minified version instantly. Removes comments, collapses whitespace, and strips unnecessary quotes.
Image to Base64 Converter
Free image to Base64 converter. Upload any image and get its Base64 data URI. Copy as raw Base64, an HTML img tag, or a CSS background url() value.
JavaScript Beautifier
Free JavaScript beautifier. Paste minified JS and get clean, formatted code with proper indentation. Choose 2-space, 4-space, or tab indent style.
Line Counter & Analyzer
Free line counter and text analyzer. Count total lines, blank lines, unique lines, and duplicates. Find the longest and shortest lines instantly.
Morse Code Translator
Free Morse code translator. Convert text to Morse code and back. Play audio beeps for each letter and view the full Morse alphabet reference chart.
Random Number Generator
Free random number generator. Generate cryptographically secure random numbers with custom min, max, and count. Choose unique or allow duplicates.
Text Repeater
Free text repeater tool. Enter any text and a repeat count to generate repeated output. Choose separator, add line numbers, and copy the result instantly.
URL Slug Generator
Free URL slug generator. Convert any text into a clean, SEO-friendly slug. Choose hyphen or underscore separator. Great for blog posts and products.
.htaccess Redirect Generator
Free .htaccess redirect generator for Apache. Create 301, 302, www/non-www, HTTPS, and custom redirect rules instantly. No signup required.
Aspect Ratio Calculator
Free online aspect ratio calculator. Resize dimensions proportionally for images, videos, and responsive design. Instant results, no signup needed.
Base64 Encoder & Decoder
Free Base64 encoder and decoder. Convert text to Base64 or decode Base64 strings instantly in your browser. Supports UTF-8 encoding and bulk input.
Chmod Calculator
Free chmod calculator for Unix file permissions. Toggle read, write, and execute for owner, group, and others to get the numeric chmod value instantly.
Color Converter (HEX, RGB, HSL)
Free color converter tool. Convert colors between HEX, RGB, and HSL formats with live preview and a built-in color picker. No signup required.
Crontab Expression Generator
Free crontab expression generator. Build cron schedules visually with human-readable descriptions and next run times. No signup required.
CSS Gradient Generator
Free CSS gradient generator. Create linear and radial gradients visually with live preview and copy-ready CSS code for your web projects.
CSV to JSON Converter
Convert CSV to JSON with quoted fields, multiline values, and clear errors. Preserve leading zeros and long IDs as strings; review and download the result.
Emoji Picker & Search
Free emoji picker and search tool. Browse all emoji categories, search by name or keyword, and click to copy. Works on any device, no signup needed.
Favicon Generator (Text to Icon)
Free favicon generator from text or emoji. Create website icons and download as ICO, PNG, or SVG. No design skills needed, instant results.
Hash Generator (SHA-1, SHA-256, SHA-512)
Generate SHA-1, SHA-256, and SHA-512 hashes from text using your browser’s local Web Crypto API. Compare digests without uploading the text.
HTML Entity Encoder & Decoder
Free HTML entity encoder and decoder. Convert special characters to HTML entities or decode entities back to text instantly in your browser.
HTTP Status Codes Reference
Free HTTP status codes reference. Searchable list of all HTTP response codes with descriptions, explanations, and common usage examples for developers.
Image Compressor (Browser-Based)
Free browser-based image compressor. Reduce JPEG and PNG file sizes with adjustable quality settings. Nothing is uploaded to any server. 100% private.
IP Address Lookup
Free IP address lookup tool. Find your public IP and get geolocation details including country, city, ISP, and timezone. No signup required.
JSON Formatter & Validator
Free JSON formatter and validator. Paste messy JSON and instantly format, validate, and beautify it with syntax highlighting and error line numbers.
JSON to CSV Converter
Convert JSON to CSV using keys from every record. Choose a nested-value policy, review formula-like text, and preserve identifiers as strings before export.
JSON to YAML Converter
Free JSON to YAML converter and vice versa. Paste JSON or YAML and get clean, readable output in the other format. Runs entirely in your browser.
JWT Token Decoder
Decode JWT headers and payloads locally in your browser. Inspect token fields without uploading the token; decoding does not verify its signature.
Lorem Ipsum Generator
Free Lorem Ipsum text generator. Create placeholder paragraphs, sentences, or words for your designs. Copy-ready output with customizable length.
Markdown to HTML Preview
Free Markdown to HTML previewer. Write Markdown on the left and see rendered HTML in real time on the right. No signup, runs in your browser.
Meta Tag Generator for SEO
Free meta tag generator for SEO, Open Graph, and Twitter Cards. Generate copy-paste-ready HTML meta tags for your website in seconds.
Number Base Converter (Binary, Octal, Hex, Decimal)
Free number base converter. Convert between binary, octal, decimal, and hexadecimal instantly as you type. Great for developers and students.
Percentage Calculator
Free percentage calculator. Quickly compute what is X% of Y, X is what percent of Y, and percentage increase or decrease. Instant results online.
QR Code Generator
Free QR code generator for URLs, text, WiFi credentials, and more. Generate and download QR codes as PNG instantly. No signup or watermark.
Regex Tester & Debugger
Free regex tester and debugger. Test regular expressions in real time with match highlighting, capture groups, and flag support. No signup needed.
Robots.txt Generator
Free robots.txt generator for your website. Control what search engines can and cannot crawl with an easy visual builder. No coding required.
Screen Resolution & Display Info
Free screen resolution detector. See your display resolution, viewport size, pixel ratio, color depth, and browser info instantly. No signup needed.
SQL Formatter & Beautifier
Free SQL formatter and beautifier. Format SELECT, INSERT, UPDATE, CREATE and other SQL queries with proper indentation and syntax highlighting.
Strong Password Generator
Free strong password generator. Create secure, random passwords with customizable length and character types. Copy with one click. No signup needed.
Text Case Converter
Free text case converter. Transform text between UPPERCASE, lowercase, Title Case, camelCase, snake_case, and more formats instantly online.
Text Diff Checker
Free text diff checker. Compare two texts side by side with additions, deletions, and changes highlighted. Runs in your browser, no data uploaded.
Text to Binary Converter
Free text to binary converter. Convert text to binary code and binary back to text. Also supports HEX and octal conversions. No signup required.
Unit Converter (Length, Weight, Temperature)
Free unit converter for length, weight, and temperature. Convert km to miles, kg to lbs, Celsius to Fahrenheit, and more with instant results.
Unix Timestamp Converter
Free Unix timestamp converter. Convert Unix epoch timestamps to human-readable dates and vice versa. Shows the current timestamp live. No signup needed.
URL Encoder & Decoder
Free URL encoder and decoder. Encode or decode URLs and query strings with full support for special characters and UTF-8. Runs in your browser.
UUID Generator (v4)
Free UUID v4 generator. Generate random UUIDs in bulk and copy one or many with a single click. No signup needed, runs entirely in your browser.
Word Counter & Text Statistics
Free word counter and text statistics tool. Count words, characters, sentences, paragraphs, and estimate reading time in real time as you type.