JSON Formatter & Validator
Format, validate, or compact JSON with useful local errors.
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Browse every formatter, converter, comparison tool, and generator by category.
Featured toolJSON Formatter & ValidatorFormat, validate, or compact JSON with useful local errors.
Development
Format code and configuration, build commands, and use practical developer references.
JSON to CSV Converter
Convert an array of JSON objects into downloadable CSV.
Open toolGit Cheatsheet
Search and copy practical Git commands for everyday workflows.
Open toolCrontab Generator
Build standard five-field Unix cron expressions.
Open toolJSON Minifier
Validate JSON and remove unnecessary whitespace.
Open toolSQL Formatter
Format common SQL statements into readable clauses.
Open toolChmod Calculator
Build numeric and symbolic Unix file permissions.
Open toolDocker Run to Compose Converter
Turn common docker run options into a Compose service.
Open toolXML Formatter
Indent XML and detect mismatched element tags.
Open toolYAML Formatter
Parse and consistently format YAML documents.
Open toolEmail Normalizer
Trim an address and normalize its domain safely.
Open toolRegex Tester
Test JavaScript regular expressions and inspect matches.
Open toolRegex Cheatsheet
Search common JavaScript regular-expression syntax.
Open toolRandom Port Generator
Generate unique random port candidates inside a configurable range.
Open toolWeb
Inspect and transform common values used in web development.
JSON Diff
Compare JSON structurally and find added, removed, or changed values.
Open toolURL Encoder & Decoder
Encode or decode URL components and complete URLs.
Open toolHTML Entity Encoder & Decoder
Escape HTML-sensitive characters or decode common named and numeric entities.
Open toolURL Parser
Break a complete URL into its protocol, host, path, query, and fragment.
Open toolSlugify String
Turn a title or phrase into a clean lowercase URL slug.
Open toolDevice Information
Inspect browser-exposed screen, platform, hardware, locale, and connection details.
Open toolBasic Auth Generator
Build an HTTP Basic Authorization header from a username and password.
Open toolOpen Graph Meta Generator
Generate escaped Open Graph title, description, URL, image, type, and site tags.
Open toolOTP Code Generator
Generate one or many cryptographically random numeric one-time-code candidates.
Open toolMIME Types
Search common media types by name, file extension, or description.
Open toolJWT Parser
Decode JWT header and payload JSON and inspect common time claims.
Open toolKeycode Info
Capture a keyboard event and inspect key, code, location, modifiers, and legacy keyCode.
Open toolHTML WYSIWYG Editor
Format local rich text and copy the generated HTML source.
Open toolUser-Agent Parser
Parse browser, engine, operating system, device, and CPU hints from a User-Agent.
Open toolHTTP Status Codes
Search a practical reference of common HTTP response status codes.
Open toolText
Compare and work with plain text directly in your browser.
Text Diff
Compare two text versions with inline or line-by-line changes.
Open toolText Statistics
Count words, characters, lines, sentences, and estimated reading time.
Open toolLorem Ipsum Generator
Generate placeholder paragraphs with a controlled sentence count.
Open toolEmoji Picker
Search, browse, combine, and copy commonly used emoji.
Open toolString Obfuscator
Disguise and restore text with a reversible key-based transformation.
Open toolNumeronym Generator
Shorten long words into forms such as i18n and a11y.
Open toolASCII Art Text Generator
Render short text with a compact five-row block font.
Open toolData
Validate and format real-world structured identifiers.
Crypto
Generate, hash, sign, and inspect cryptographic development values.
UUID Generator
Generate one or many cryptographically random UUID v4 values.
Open toolHash Generator
Create SHA-256, SHA-384, or SHA-512 digests from text.
Open toolPassword Strength Analyzer
Review password length, character variety, and obvious weak patterns locally.
Open toolToken Generator
Generate secure random hexadecimal, Base64URL, or alphanumeric tokens.
Open toolBcrypt
Create Bcrypt hashes and verify text against an existing Bcrypt hash.
Open toolULID Generator
Generate time-sortable 128-bit Universally Unique Lexicographically Sortable Identifiers.
Open toolEncrypt / Decrypt Text
Encrypt text with AES-256-GCM and decrypt DevMate payloads with a password.
Open toolBIP39 Passphrase Generator
Generate checksum-valid English BIP39 mnemonic phrases with secure randomness.
Open toolHMAC Generator
Create SHA-256, SHA-384, or SHA-512 keyed message authentication codes.
Open toolRSA Key Pair Generator
Generate exportable 2048-bit or 3072-bit RSA public and private keys.
Open toolPDF Signature Checker
Inspect a local PDF for signature dictionaries and ByteRange coverage.
Open toolConverters
Convert encodings, dates, and developer-friendly values.
Base64 Encoder & Decoder
Encode or decode UTF-8 text safely in the browser.
Open toolTimestamp Converter
Convert Unix timestamps and readable dates in local time or UTC.
Open toolCase Converter
Convert text to title, sentence, camel, snake, kebab, or letter case.
Open toolInteger Base Converter
Convert exact integers between binary, octal, decimal, hexadecimal, and base 36.
Open toolRoman Numeral Converter
Convert integers to Roman numerals and canonical Roman numerals back to integers.
Open toolBase64 File Converter
Encode a local file as Base64 or decode Base64 into a downloadable file.
Open toolColor Converter
Convert hexadecimal colors into equivalent RGB and HSL values.
Open toolText to NATO Alphabet
Spell letters and digits with the NATO phonetic alphabet.
Open toolText to ASCII Binary
Convert 7-bit ASCII text to 8-bit binary groups and back.
Open toolText to Unicode
Convert text into Unicode code points and decode code points back to text.
Open toolYAML ↔ JSON Converter
Convert YAML to formatted JSON and JSON back to readable YAML.
Open toolYAML ↔ TOML Converter
Convert YAML configuration to TOML and TOML back to readable YAML.
Open toolJSON ↔ TOML Converter
Convert JSON objects to TOML and TOML configuration back to formatted JSON.
Open toolList Converter
Convert lists between lines, commas, semicolons, and pipes.
Open toolXML ↔ JSON Converter
Convert XML structures to JSON and compatible JSON objects back to formatted XML.
Open toolMarkdown to HTML Converter
Convert GitHub-flavored Markdown into HTML source.
Open toolNetwork
Calculate, inspect, convert, and generate local network values.
IPv4 Subnet Calculator
Calculate IPv4 networks, masks, broadcasts, host ranges, and address counts.
Open toolIPv4 Address Converter
Convert IPv4 addresses between dotted, decimal, hexadecimal, and binary forms.
Open toolIPv4 Range Expander
Expand an inclusive IPv4 start and end range into individual addresses.
Open toolMAC Address Lookup
Normalize a MAC address and inspect its OUI, scope, and transmission type.
Open toolMAC Address Generator
Generate random locally administered unicast MAC addresses.
Open toolIPv6 ULA Generator
Generate random locally assigned IPv6 Unique Local Address /48 prefixes.
Open toolImages & QR Codes
Generate SVG placeholders and create or decode QR images locally.
QR Code Generator & Decoder
Generate a QR code from text or a URL, or upload a QR image to read its value.
Open toolWiFi QR Code Generator & Decoder
Generate a WiFi connection QR code or decode an uploaded QR image and inspect its network value.
Open toolSVG Placeholder Generator
Generate a lightweight SVG placeholder with custom dimensions, colors, and text.
Open toolMath
Evaluate expressions, percentages, and progress estimates.
Math Evaluator
Safely evaluate arithmetic expressions, constants, and common math functions.
Open toolETA Calculator
Estimate remaining duration and completion time from current progress.
Open toolPercentage Calculator
Compare error rates, latency changes, rollout shares, and percentage points.
Open toolMeasurement
Measure time, temperature, and benchmark performance.