Developer
Free online development tool collection, providing various commonly used tools for programmers, such as JSON format validation, timestamp conversion, regular expression testing, CRON expression generation, UUID batch generation, base conversion, encoding and decoding, etc., which can be directly used by browsers to improve development efficiency.
Regex
Regex Tester
Test regular expressions live with match highlighting and group expansion
JSON
JSON Formatter
Beautify, minify and validate JSON with structure statistics
Hash
Text Hash Generator
Compute MD5 and SHA digests for text with case switching
UUID
UUID Generator
Batch-generate standard UUID v4 with case and hyphen options, automatic dedup and one-click copy.
URL Parse
URL Parser
Paste a URL to break it into protocol, host, port, path, hash and query params with auto-scheme and decoding.
Unicode
Character Encoding Viewer
Show each character's code point, UTF-8 bytes and UTF-16 units, handling Chinese and emoji surrogate pairs.
Timestamp
Timestamp Converter
Convert seconds/ms timestamps to and from local and UTC date-time, auto-detecting seconds vs milliseconds.
SQL Format
SQL Formatter
Beautify SQL with uppercase keywords, indented clauses and untouched string literals.
SemVer
SemVer Compare
Parse semantic versions, compare two version strings and sort a list with a per-part breakdown.
Random
Random Number Generator
Generate random numbers in a range with a chosen count, with dedup, sorting and a reproducible seed.
Lorem
Lorem Generator
Generate Chinese or English placeholder text by words, sentences or paragraphs, optionally starting with Lorem ipsum.
JWT
JWT Decoder
Paste a JWT to decode its Header and Payload, list standard claims and show expiry status.
JSON CSV
CSV ↔ JSON Converter
Convert between CSV and JSON in both directions, following RFC4180 escaping with headers and custom delimiters.
HTTP Codes
HTTP Status Codes
Built-in reference of common HTTP 1xx to 5xx status codes, searchable by number or name and by category.
HTML Preview
HTML Live Preview
Write HTML on the left and render it live in a sandboxed iframe on the right, with scripts disabled.
Diff
Text Diff
Side-by-side row-level LCS diff that highlights additions and deletions, with stats and merged copy.
Cron
Cron Expression Builder
Visually configure minute, hour, day, month and weekday to build a standard cron expression with a readable description and next run times.