Developer Tools
296 free online developer tools across 8 categories — encoding, encryption, compression, formatters, converters, generators and more. All tools run locally in your browser; your data never leaves your device.
Encoding & Encryption(37)
- Base64— Encode and decode Base64 with UTF-8 support.
- URL Encoder— Percent-encode and decode URLs.
- Unicode Converter— Convert text to Unicode escapes and back.
- HTML Entity— Encode and decode HTML entities.
- Number Base Converter— Convert between binary, octal, decimal, hex.
- Hash Generator— Generate MD5, SHA-1, SHA-256, SHA-512 hashes.
- HMAC Generator— Generate HMAC signatures with SHA algorithms.
- JWT Decoder— Decode JWT tokens and inspect header and payload.
- UUID / NanoID Generator— Generate UUID v4 and NanoID in bulk.
- Password Generator— Generate secure random passwords.
- AES Encryption— AES-GCM-256 encrypt/decrypt with PBKDF2 key derivation.
- RSA Tool— Generate RSA-2048 key pairs and encrypt/decrypt with RSA-OAEP.
- Bcrypt Hash— Hash passwords with bcrypt and verify against hashes.
- ULID Generator— Generate Universally Unique Lexicographically Sortable Identifiers.
- Token Generator— Generate random tokens with custom alphabet and length.
- Password Strength Analyser— Analyse password strength and estimate crack time.
- OTP Code Generator— Generate TOTP 2FA codes from a Base32 secret.
- JSON Schema Validator— Validate JSON data against a JSON Schema (draft-07).
- JWT Signer— Sign JWT tokens with HS256/HS384/HS512 (HMAC).
- Hash Verifier— Compare text against an expected MD5/SHA hash.
- SSH Key Generator— Generate RSA key pairs as OpenSSH and PKCS#8 PEM.
- Base32 Encoder/Decoder— Encode and decode Base32, used for OTP secrets and case-insensitive systems.
- Base58 Encoder/Decoder— Base58 encode/decode (Bitcoin/IPFS style, no ambiguous chars).
- Base85 Encoder/Decoder— Ascii85/Base85 encode/decode for high-density binary text.
- Hex Encoder/Decoder— Convert text to hexadecimal string and back.
- Punycode Converter— Convert Unicode domain names to Punycode (IDN) and back.
- Quoted-Printable Encoder/Decoder— MIME Quoted-Printable encode/decode for email non-ASCII text.
- ROT13 Cipher— ROT13 substitution cipher (encrypt and decrypt are the same).
- Caesar Cipher— Caesar cipher encrypt/decrypt with adjustable shift.
- Vigenère Cipher— Vigenère cipher encrypt/decrypt with keyword-based polyalphabetic substitution.
- Morse Code Translator— Translate text to Morse code and back, with audio playback.
- PBKDF2 Key Generator— Derive PBKDF2 keys with adjustable iterations and salt.
- scrypt Key Generator— Generate scrypt derived keys with adjustable N/r/p parameters.
- Argon2 Hash Generator— Generate Argon2id/2d/2i hashes with memory and time cost.
- NanoID Generator— Generate compact, URL-safe NanoID unique identifiers.
- CRC Checksum Calculator— Compute CRC-8/16/32 cyclic redundancy checks.
- X.509 Certificate Parser— Parse SSL/TLS certificates in PEM/DER and inspect fields.
Compression(33)
- Gzip / Brotli Compressor— Compress and decompress text with gzip and deflate streams.
- Deflate Compressor— Deflate algorithm compress/decompress (native CompressionStream).
- Zlib Compressor— Zlib format (RFC 1950) compress and decompress.
- Raw Deflate Compressor— Raw Deflate stream without zlib header compress/decompress.
- LZ-String Compressor— lz-string compress/decompress for short text in URLs/LocalStorage.
- LZUTF-8 Compressor— LZUTF-8 compress/decompress optimized for UTF-8 text.
- LZMA Compressor— LZMA/LZMA2 high-ratio compress and decompress.
- LZ4 Decompressor— LZ4 format decompression (lz4js) for fast decompression.
- LZW Compressor— LZW dictionary compress/decompress (classic GIF algorithm).
- LZ77 Compressor— LZ77 sliding window compress/decompress for learning.
- Run-Length Encoder— RLE run-length encoding for data with repeated chars.
- Huffman Encoder— Huffman coding compress/decompress based on frequency.
- Brotli Decompressor— Decompress Brotli streams using DecompressionStream.
- Gzip Decompressor— Decompress Gzip streams using DecompressionStream.
- GZ File Creator— Package a file into a single .gz archive.
- TAR.GZ Archive Creator— Package multiple files and gzip-compress to .tar.gz.
- TAR.GZ Archive Extractor— Extract .tar.gz and list/download inner files.
- Brotli File Creator— Compress data to a .br file with Brotli.
- ZIP Archive Creator— Select multiple files to generate a .zip archive.
- ZIP Archive Extractor— Upload .zip to extract and list/download files.
- ZIP Archive Viewer— View .zip file list and sizes without extracting.
- TAR Archive Creator— Package files into a .tar archive without compression.
- TAR Archive Extractor— Extract .tar archives and list inner files.
- GZ File Extractor— Decompress a single .gz file to restore content.
- Smaz Short-String Compressor— Smaz algorithm for compressing short English strings.
- Shoco Text Compressor— Shoco algorithm for lightweight English text compression.
- Compression Benchmark— Compare multiple algorithms' ratio and time on same input.
- Text Compressor— Universal text compression with auto-best-algorithm selection.
- Binary File Compressor— Compress any binary file and download.
- Archive Inspector— Auto-detect zip/tar/gz format and show structure.
- File Compressor— Multi-format (gzip/deflate/brotli) file compressor.
- Minify & Compress Pipeline— Minify (JSON/JS) then binary-compress for smallest size.
- Compression Ratio Calculator— Calculate original vs compressed size ratio and savings.
Image Tools(37)
- Image Compressor— Compress JPEG/WebP images with a quality slider.
- Image Watermark— Add text watermarks with 9-point positioning.
- Image to ICO— Convert images to Windows .ico icons at 16–256px.
- Image ↔ Base64— Convert images to Base64 data URLs and back.
- EXIF Remover— Strip EXIF, GPS and camera metadata from photos.
- Image Resizer— Resize images with optional aspect-ratio lock.
- Image Format Converter— Convert between PNG, JPEG and WebP formats.
- QR Code Decoder— Decode QR codes from uploaded images.
- SVG Optimizer— Minify SVG by removing comments, metadata and whitespace.
- Image Cropper— Crop images with adjustable aspect ratio via Canvas.
- Image Rotator— Rotate images by any angle and export.
- Image Flipper— Flip images horizontally or vertically.
- Image Filter— Apply grayscale, sepia, invert and other Canvas filters.
- Image Color Picker— Pick colors from any image pixel, output HEX/RGB.
- Image to ASCII Art— Convert images to ASCII art with adjustable resolution.
- Image to SVG— Trace bitmap images into SVG vector paths.
- Image to AVIF— Convert images to AVIF format with high compression.
- Image to WebP— Convert images to WebP format with quality control.
- Image to JPG— Convert images to JPG with quality and background color.
- Image to PNG— Convert images to PNG (lossless).
- Image Thumbnail Generator— Batch generate thumbnails at specified sizes.
- Image Metadata Viewer— View EXIF/IPTC/XMP metadata from images.
- Image Steganography— Hide and extract text in image LSB pixels.
- Image Color Quantizer— Reduce image color depth (e.g. to 256 colors).
- Image Blur Tool— Apply Gaussian/box blur to images.
- Image Sharpen Tool— Sharpen images with convolution to enhance edges.
- Brightness & Contrast Adjuster— Adjust brightness, contrast, and saturation.
- RGBA Channel Extractor— Separate and view R/G/B/Alpha channels.
- Image Color Inverter— Invert image colors (negative effect).
- Image Border Adder— Add custom color and width borders to images.
- Round Image Corners— Add rounded corners to images and export PNG.
- Image Collage Maker— Combine multiple images into one with layout options.
- Image Background Remover— Remove image background automatically in browser.
- Add Text to Image— Overlay text watermark/title onto images.
- Image Pixelator— Pixelate images with adjustable block size.
- Image Histogram— Plot RGB channel histograms for images.
- Favicon Generator— Generate multi-size favicons (16/32/48/180) from image.
JSON & Data Format(37)
- JSON Formatter— Format, validate, and minify JSON.
- JSON to CSV— Convert JSON array to CSV format.
- CSV to JSON— Convert CSV data to JSON array.
- JSON to XML— Convert JSON objects to XML format.
- XML to JSON— Convert XML to JSON using DOMParser.
- JSON to YAML— Convert JSON to YAML format.
- YAML to JSON— Parse YAML and convert to JSON.
- JSON to TypeScript— Generate TypeScript interfaces from JSON.
- JSON to TOML— Convert JSON objects to TOML configuration format.
- TOML to JSON— Parse TOML and convert to JSON format.
- JSON Diff— Compare two JSON documents and highlight differences.
- YAML Validator— Validate and beautify YAML with consistent indentation.
- JSONPath Tester— Evaluate JSONPath expressions to extract JSON values.
- JSON Minifier— Compress JSON by removing whitespace for minimal size.
- JSON Validator— Validate JSON syntax and highlight error positions.
- JSON to Go Struct— Convert JSON to Go struct definitions.
- JSON to Java Class— Convert JSON to Java class with type inference.
- JSON to C# Class— Convert JSON to C# class definitions.
- JSON to Rust Struct— Convert JSON to Rust serde structs.
- JSON to PHP Class— Convert JSON to PHP class with properties.
- JSON to Kotlin Data Class— Convert JSON to Kotlin data class.
- JSON to Swift Struct— Convert JSON to Swift Codable struct.
- JSON to Protobuf Schema— Convert JSON to Protobuf .proto message definitions.
- JSON to SQL— Convert JSON array to INSERT statements or DDL.
- JSON to HTML Table— Render JSON array as an HTML table.
- JSON to Properties— Convert JSON to Java .properties key-value file.
- JSON to INI— Convert JSON to INI configuration file format.
- JSON to Query String— Convert JSON object to URL query string.
- CSV Formatter— Beautify CSV with aligned columns and custom delimiter.
- CSV Viewer— Display CSV content in a sortable table.
- XML Formatter— XML beautify/indent with adjustable indent width.
- XML Validator— Validate XML well-formedness and report errors.
- XML Minifier— Compress XML by removing whitespace and comments.
- YAML Formatter— YAML beautify and indent normalization.
- TOML Validator— Validate TOML syntax and parse to object.
- INI Parser— Parse/edit INI configuration with export support.
- JSON Tree Viewer— Browse large JSON in a collapsible tree structure.
Time & Date(37)
- Timestamp Converter— Convert Unix timestamps to dates and back.
- Date Calculator— Add/subtract dates and calculate differences.
- Timezone Converter— Convert time across world timezones.
- Cron Parser— Parse cron expressions and show next runs.
- Temperature Converter— Convert between Celsius, Fahrenheit, and Kelvin.
- Chronometer— Precision stopwatch with lap times and millisecond accuracy.
- Date Difference Calculator— Calculate the difference between two dates in years/days/hours.
- Date Add/Subtract— Add or subtract years/months/days/hours/minutes/seconds from a date.
- Countdown Timer— Countdown to a specified moment with notifications.
- Pomodoro Timer— Pomodoro technique timer with work/break cycles.
- World Clock— Display current time in multiple cities simultaneously.
- Age Calculator— Calculate exact age from birthday and days to next birthday.
- Interval Timer— Configurable work/rest interval cycling timer.
- Alarm Clock— Set an alarm with browser notifications.
- 12h/24h Time Converter— Convert between 12-hour and 24-hour time formats.
- Business Days Calculator— Calculate business days, excluding weekends and holidays.
- Date Format Converter— Convert between ISO/US/EU/Chinese date formats.
- ISO 8601 Validator— Validate if a string conforms to ISO 8601 date-time format.
- Relative Time Generator— Generate '2 hours ago' style relative time (multilingual).
- Time Ago Calculator— Calculate relative description of how long ago a time was.
- Calendar Generator— Generate a calendar view for a specified month.
- Leap Year Checker— Check if a year is a leap year and explain the rules.
- Day of Week Calculator— Find which day of the week a date falls on.
- Week Number Calculator— Calculate ISO 8601 week number for a date.
- Lunar Calendar Converter— Convert between Gregorian and Chinese lunar calendar.
- Julian Date Converter— Convert between Gregorian date and Julian Day Number (JDN).
- Sleep Cycle Calculator— Recommend bed/wake times based on 90-minute sleep cycles.
- Meeting Planner— Find suitable meeting times across timezones for all participants.
- Duration Calculator— Calculate total duration of a time period (hours/minutes/seconds).
- Natural Language Date Parser— Parse 'next Friday 3pm' style natural language dates.
- Time Zone Map— Visualize world time zones and current times.
- Daylight Saving Info— Query daylight saving start/end times for a timezone.
- Deadline Calculator— Back-calculate milestone times from a deadline.
- Timestamp Unit Converter— Convert between seconds/milliseconds/microseconds/nanoseconds timestamps.
- Crontab Generator— Visually generate cron expressions and preview next runs.
- iCal Event Generator— Generate .ics calendar event files for import.
- Duration Formatter— Convert between ISO 8601 duration (PT1H30M) and readable text.
Text & Code(36)
- Text Counter— Count characters, words, lines, paragraphs.
- Text Cleaner— Remove extra spaces, blank lines, and breaks.
- Case Converter— Convert to UPPER, lower, camelCase, snake_case.
- Markdown Previewer— Preview Markdown rendered as HTML in real time.
- HTML ↔ Markdown— Convert between HTML and Markdown.
- Code Diff— Compare two text snippets and highlight differences.
- SQL Formatter— Format and beautify SQL queries.
- Regex Tester— Test regex with live match highlighting.
- Roman Numeral Converter— Convert between Roman numerals and Arabic numbers.
- Text ↔ Binary— Convert text to binary representation and back.
- Email Validator— Validate and normalise email addresses.
- String Reverser— Reverse text by characters, words, or lines.
- Math Evaluator— Evaluate mathematical expressions safely.
- Slugify— Convert text to URL-friendly slugs.
- Percentage Calculator— Calculate percentages, increases, and decreases.
- ETA Calculator— Estimate completion time from progress and rate.
- NATO Phonetic Alphabet— Convert text to NATO phonetic alphabet code words.
- HTML/CSS/JS Minifier— Minify HTML, CSS and JavaScript by stripping comments and whitespace.
- Regex Explainer— Break a regex into tokens and explain each part in plain English.
- Bitwise Calculator— AND, OR, XOR, NOT, shifts and rotations on 8–64-bit integers.
- Data URI Converter— Encode text to data URIs and decode data URLs back to text.
- Text to Hex Converter— Convert text to hexadecimal representation.
- Text to Octal Converter— Convert text to octal representation.
- Text to Decimal Converter— Convert text to decimal code point representation.
- Text Line Sorter— Sort lines alphabetically/by length/numerically, asc or desc.
- Line Deduplicator— Remove duplicate lines, keep first or last occurrence.
- Line Joiner— Join multiple lines into one with a custom separator.
- Text Splitter— Split text by delimiter or length into multiple segments.
- Line Number Adder— Add line number prefixes to each line.
- Tab/Space Converter— Convert between tabs and spaces with custom width.
- Whitespace Trimmer— Remove leading/trailing/extra whitespace and blank lines.
- Text Escaper— Escape text for HTML/JS/Regex/Shell contexts.
- Find and Replace— Find and replace with regex and capture group support.
- CSV Escaper— Add quote escaping for CSV fields.
- SQL String Escaper— Escape special characters in SQL string literals.
- String Case Detector— Detect if string is camel/snake/kebab/const case.
Generators & Design(37)
- Color Tool— Convert color formats and generate palettes.
- CSS Gradient Generator— Generate CSS gradients with live preview.
- QR Code Generator— Generate QR codes from text or URLs.
- ASCII Art Generator— Convert text to ASCII art.
- Token Estimator— Estimate LLM token count for text.
- WiFi QR Code Generator— Generate QR codes to join WiFi networks.
- Lorem Ipsum Generator— Generate Lorem Ipsum placeholder text.
- Color Shades— Generate tints and shades of any color.
- UUID v7 Generator— Generate time-sorted UUID version 7 (RFC 9562) identifiers.
- PEM Certificate Parser— Parse X.509 certificates from PEM format and inspect fields.
- Barcode Generator— Generate CODE128/EAN/UPC barcodes as PNG/SVG.
- Data Matrix Code Generator— Generate Data Matrix 2D codes (square dot grid).
- Aztec Code Generator— Generate Aztec 2D codes, common in tickets.
- PDF417 Barcode Generator— Generate PDF417 stacked barcodes with large data capacity.
- Color Palette Generator— Generate complementary/analogous/triadic palettes from seed color.
- CSS Box Shadow Generator— Visually generate box-shadow CSS with live preview.
- CSS Border Radius Generator— Visually adjust four-corner radius and generate CSS.
- Flexbox Generator— Visually generate flexbox layout CSS.
- CSS Grid Generator— Drag to generate grid-template layout CSS.
- CSS Transform Generator— Visually generate translate/rotate/scale/skew.
- CSS Animation Generator— Edit keyframes visually and generate @keyframes.
- CSS Text Shadow Generator— Generate multi-layer text-shadow CSS.
- Placeholder Image Generator— Generate placeholder images with custom size/color/text.
- Avatar Generator— Generate identicon geometric avatars from strings.
- Stripe Pattern Generator— Generate SVG/Canvas stripe patterns with adjustable direction.
- Dot Pattern Generator— Generate dot grid background patterns, export SVG.
- Noise Pattern Generator— Generate Perlin/random noise texture images.
- Color Scheme from Image— Extract dominant colors from image to generate palette.
- Skeleton Loader Generator— Generate skeleton screen loading animation CSS.
- Glassmorphism Generator— Generate frosted glass effect CSS (blur + transparency).
- Neumorphism Generator— Generate neumorphic UI style CSS.
- CSS Clip-Path Generator— Visually draw paths to generate clip-path.
- Cubic Bezier Generator— Visually adjust bezier curve to generate easing function.
- CSS Easing Generator— Generate and preview CSS transition-timing-function.
- Tailwind Color Finder— Find the closest Tailwind color palette class for a color.
- Material Color Picker— Material Design color palette picker, output color values.
- Polygon Shape Generator— Generate polygon/star SVG and clip-path.
Network & Ops(42)
- IP Lookup— Query IP address geolocation and ISP info.
- Subnet Calculator— Calculate IPv4 subnet details from CIDR.
- DNS Lookup— Query DNS records via Google DNS over HTTPS.
- User-Agent Parser— Parse browser, OS, and device from UA string.
- HTTP Status Codes— Reference for all HTTP status codes.
- HTTP Request Tester— Send GET/POST/PUT/DELETE requests and inspect responses.
- URL Parser— Parse a URL into its components: protocol, host, path, query.
- Device Information— Show browser, OS, screen, and device info from the client.
- MAC Address Lookup— Look up the vendor of a MAC address.
- MIME Type Lookup— Look up MIME types by file extension and vice versa.
- File Hash Checksum— Drop a file to compute SHA-1, SHA-256, SHA-384 and SHA-512 checksums.
- Show My IP Address— Display current client public IP and browser IP info.
- IPv6 Address Generator— Generate random or prefix-based IPv6 addresses.
- IPv4 to IPv6 Converter— Convert IPv4 to IPv6 mapped address (::ffff:a.b.c.d).
- CIDR to IP Range Converter— Convert CIDR block to start/end IP range.
- IP Range to CIDR Converter— Convert start/end IP to CIDR list.
- IP Address Validator— Validate IPv4/IPv6 format and legality.
- MAC Address Generator— Generate random or OUI-based MAC addresses.
- Query String Parser— Parse URL query params to key-value pairs with edit support.
- URL Builder— Compose base, path, query params into full URL.
- HTTP Headers Parser— Parse raw HTTP header text to structured key-values.
- Cookie Parser— Parse document.cookie string to object.
- Basic Auth Header Generator— Generate Authorization: Basic header from username/password.
- Bearer Token Header Generator— Generate Authorization: Bearer header with JWT prefill.
- DNS-over-HTTPS Client— Query DNS records via fetch to DoH endpoints.
- WebSocket Client Tester— Connect to WS server, send/receive messages with logs.
- Server-Sent Events Tester— Subscribe via EventSource and display SSE stream.
- WebRTC Connection Tester— Establish RTCPeerConnection to verify connectivity and ICE.
- HTTP Methods Reference— Query GET/POST/PUT/DELETE method semantics and idempotency.
- TCP Port Reference— Query common port-to-service mappings (80/443/3306…).
- Well-Known Port Lookup— Look up IANA registered ports by port or service name.
- Content Security Policy Builder— Visually compose CSP header directives.
- CORS Rule Builder— Generate CORS response headers (Access-Control-*).
- Robots.txt Generator— Generate robots.txt rules for a site.
- Sitemap XML Generator— Generate sitemap.xml from a URL list.
- .htaccess Generator— Generate redirect/cache/auth .htaccess rules.
- Nginx Config Generator— Generate reverse proxy/static site Nginx configs.
- Docker Compose Generator— Visually generate docker-compose.yml.
- Dockerfile Generator— Generate Dockerfile templates by language/runtime.
- .gitignore Generator— Generate .gitignore templates by language/IDE selection.
- CI/CD YAML Generator— Generate GitHub Actions / GitLab CI pipeline templates.
- .env File Generator— Manage key-values to generate .env and .env.example.
Last updated: 2026-08-01