- UUID GeneratorGenerate v1/v4 UUIDs in batches with case and hyphen options.
- Regex TesterTest expressions, inspect captured groups and preview replacements.
- JWT DecoderDecode JWT headers and payloads locally and inspect token dates.
- Code Formatter / MinifierBeautify or minify HTML, CSS and JavaScript without running the code.
- Number Base ConverterConvert signed large integers between binary, octal, decimal and hexadecimal.
- Password GeneratorGenerate random passwords with secure randomness and an entropy estimate.
- Hash CalculatorCalculate MD5, SHA-1, SHA-256, SHA-384 and SHA-512 for text or files.
- Cron ParserInspect five or six field cron expressions and upcoming runs in a time zone.
- IPv4 Subnet CalculatorCalculate CIDR networks, masks, broadcasts and usable IPv4 hosts.
- SQL FormatterFormat SQL with dialect, indentation and keyword-case settings.
- TOTP / 2FA GeneratorGenerate six or eight digit TOTP codes from Base32 secrets using SHA1/256/512.
- JSON Schema GeneratorInfer a draft-07 schema, including mixed arrays, from JSON data.
- JSON Patch GeneratorCreate RFC 6902 add/remove/replace operations between two JSON documents.
- JSON PointerRead JSON nodes by RFC 6901 pointers with escaped keys and precise errors.
- JSONL ConverterConvert JSON Lines and JSON arrays with line-specific validation.
- JSON CompareCompare nested JSON and inspect added, removed and modified paths.
- Image to Base64Encode local images as a data URI, raw Base64 or a CSS background.
- Data Format ConverterConvert JSON, YAML, XML, CSV and TOML in your browser.
- curl Command GeneratorBuild a shell-quoted curl command from a URL, headers and body.
- Barcode GeneratorGenerate CODE128/CODE39 barcodes and download SVG or PNG.
- Number to ChineseConvert signed integers and decimals into Chinese readings.
- Chinese ID ValidatorCheck 18-digit Chinese ID syntax, birth date and checksum locally.
- RMB Uppercase ConverterConvert signed decimal amounts into uppercase Chinese yuan, jiao and fen.
- Unified Credit Code ValidatorValidate 18-character credit codes and inspect department and entity categories.
- Bank Card ValidatorCheck card-number syntax and Luhn checksums with common BIN references.
- Format ValidatorValidate phone, email, ID, URL, IPv4, IPv6, MAC and date values in batches.
- Text Set OperationsFind unions, intersections, differences and symmetric differences between line lists.
- WCAG Color ContrastCalculate color contrast and WCAG 2 AA/AAA thresholds for text.
- Palette GeneratorCreate monochromatic, complementary, triadic, analogous and split palettes.
- Chinese Traditional ColorsSearch traditional colors by Chinese name or pinyin and copy HEX/RGB/CMYK.
- Query String ParserParse and rebuild query strings while preserving repeated keys and blank values.
- URL Parameter EditorEdit full URL query parameters while keeping its origin, path and fragment.
- IPv6 CalculatorExpand and compress IPv6 addresses and inspect the eight segments.
- Port LookupValidate port numbers and look up common TCP/UDP services locally.
- Cookie ViewerParse Cookie headers into a readable name/value table without accessing browser cookies.
- Mock Data GeneratorGenerate synthetic names, phones, emails, IDs and addresses as JSON/CSV/text.
- Encoding ConverterConvert UTF-8 text, Base64, URL, Unicode escapes and hexadecimal.
- RSA EncryptionGenerate 2048-bit RSA-OAEP SHA-256 keys and encrypt/decrypt short messages locally.
- MAC Address GeneratorGenerate unicast MAC addresses in batches with optional vendor prefixes.
- Color PickerPick a pixel color from an image or choose a color directly. Copy HEX, RGB and HSL values and revisit recent color swatches.
- Case ConverterConvert text to uppercase, lowercase, capitalized, title, sentence, alternating or inverse case, then copy or download the result.
- Text CompareCompare original and revised text side by side. Highlight added and deleted characters, words or lines, with optional whitespace and case handling.
- JSON FormatterValidate, beautify and minify JSON. Get syntax errors, select indentation and download valid JSON.
- URL Encoder / DecoderEncode and decode URL components or complete URLs, including Chinese and special characters.
- Base64 Encoder / DecoderEncode UTF-8 text as Base64 or decode it back to text. Supports Unicode and the URL-safe alphabet.
- Timestamp ConverterConvert Unix seconds or milliseconds to dates and convert dates back to timestamps in a selected time zone.
Developer Tools
Generate, decode, format and validate code and data with tools that run locally in your browser.
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