Text / Data

JSON formatter, regex tester, text diff, and more — daily text utilities for developers and designers.

39 tools

JSON Formatter

Format, minify, and validate JSON.

Base64 Encoder/Decoder

Convert text to/from Base64.

Markdown to HTML

Convert Markdown to HTML in real-time.

Korean Jamo Fixer

Fix broken Korean character separation.

Character Counter

Count characters, words, lines, bytes in real time.

Korean↔English Converter

Fix text typed in wrong keyboard layout.

Text Case Converter

Convert to uppercase, lowercase, title case, etc.

CSV ↔ JSON Converter

Convert between CSV and JSON formats.

Text Diff

Compare two texts and highlight differences.

Hash Generator (MD5/SHA)

Generate MD5, SHA-1, SHA-256, SHA-512 hashes from text or files.

JWT Decoder

Instantly decode JWT header, payload, and metadata.

UUID Generator

Generate v4, v7, v1, and NIL UUIDs in bulk.

URL Encoder/Decoder

Percent-encode or decode URLs and query strings.

Number Base Converter

Convert between binary, octal, decimal, and hex — all four shown live with bit grouping.

Number to Korean / Hanja

Convert numbers to Korean Hangul, formal Hanja (壹貳參), English, and Japanese — for receipts and contracts.

YAML ↔ JSON Converter

Two-way YAML and JSON conversion for Kubernetes, Docker, Ansible, and CI configs.

Cron Expression Parser

Translate cron into plain English and preview the next 5 runs.

Hangul Romanizer

Convert Korean Hangul to the official Revised Romanization (RR). Name mode, hyphen, and pronunciation-aware options.

JSON → TypeScript

Generate TypeScript interfaces from JSON. Nested objects, array & union inference, optional-field option.

Sort & Dedupe Lines

Sort, dedupe, shuffle, and case-convert text by line. Tame email lists, logs, CSVs, and keyword dumps.

HTML Beautifier / Minifier

Indent minified HTML or compress it back to one line. Adjustable indent width; pre / script / style / textarea content preserved.

Korean Phone Number Formatter

Auto-format raw digits into 010-1234-5678. Detects mobile vs. area-code lines, optionally adds +82 international, batch-processes multiple numbers.

URL Slug Generator

Turn Korean / English titles into URL-safe slugs. Hangul is auto-romanized (Revised Romanization) before slugification.

Caesar Cipher (ROT13)

Shift the English alphabet by N positions. ROT13 preset, slider for any shift, symmetric (same shift to encode and decode).

JSON Diff

Compare two JSON documents and visualize added, removed, and changed keys as a tree.

HTTP Status Codes

Search every HTTP status code (200, 404, 500, …) with plain-language descriptions and use cases.

HTML Encoder/Decoder

Two-way HTML entity encoding (&, <, >, &) with named, numeric, and ASCII-only options.

MIME Type Lookup

Search file extensions and MIME types both ways, with category filters for image, audio, video, application, text, and font.

Markdown Table Builder

Build Markdown tables in a visual editor with row/column controls and per-column alignment. GitHub & Notion compatible.

Regex Tester

Test and validate regular expressions in real time.

Korean Lorem Ipsum

Generate Korean dummy text for design and development.

Roman Numeral Converter

Convert between Arabic and Roman numerals (1–3999) in either direction. 1999 ↔ MCMXCIX. For movies, watches, and classics.

Morse Code Converter

Bidirectional text ↔ Morse code with audio playback (ITU standard, 20 WPM).

CSS Beautifier / Minifier

Indent minified CSS or compress it back. Handles @media, nested rules, and comments. Configurable indent and "strip comments" option.

Lorem Ipsum (English)

Generate classic English Lorem ipsum dummy text by paragraph, sentence, or word count. Optional starting phrase.

HTML → Markdown Converter

Convert HTML to GitHub Flavored Markdown. Tables, inline code, links, and images all supported. Pick your heading and emphasis style.

Markdown TOC Generator

Auto-extract a table of contents from Markdown headings with GitHub-style anchors. Configure depth, skip the first H1, choose a bullet marker. Korean headings supported.

JSON Key Sorter

Sort JSON keys alphabetically. Deep (nested) toggle, ascending/descending, indent options. Array element order is preserved.

SQL Formatter

Beautify SQL queries with auto indentation and line breaks. Supports 8 dialects (MySQL, PostgreSQL, SQLite, BigQuery, etc.) plus keyword case and indent options.

About Text / Data

If you work with code, docs, or data, you pass through this category many times a day. Pretty-printing a wall of JSON, sanity-checking a regex, diffing two versions of a doc — these are the tools you'd otherwise jump into an IDE or another site for.

We prioritized classics that developers, analysts, QA, and PMs all touch: JSON formatter, regex tester, text diff, JWT decoder, Base64 codec. Korean-specific extras are included too: keyboard layout converter, broken-jamo fixer, Hangul romanization, number-to-Korean text.

When you handle internal logs, customer data fragments, or tokens, "does this site send my paste to a server?" matters. Every tool here runs entirely in the browser. Paste freely.

What people use it for

Beautify a minified JSON response

Paste a one-line API response and get indented, line-broken output. Sort keys or minify too.

Test a regex visually

See which spans your email/phone-validation regex matches. Groups and flags supported.

Diff two versions of a doc or snippet

Line-level and character-level views.

Convert between CSV and JSON

Take CSV out of a spreadsheet, convert to JSON for an API call; or the reverse.

Korean-language utilities

Fix qkdrkqsek → 방가워; recompose broken jamo; romanize 홍길동 → Hong Gil-dong; turn 1234567 into the spelled-out Korean.

Which tool to pick

JSON Formatter, key sort, diff, JSON → TypeScript types.
Text analysis Diff, regex tester, char count, sort/dedupe.
Encoding / hashing Base64, URL encode, JWT decoder, hash (MD5/SHA), HTML entities.
Korean tools Keyboard switch, jamo fixer, Hangul romanizer, number → Korean.
Markdown / HTML Markdown ↔ HTML, table builder, TOC generator.
Data formats CSV ↔ JSON, YAML ↔ JSON.

FAQ

Does my pasted data get sent anywhere?

No. Every tool here runs purely in the browser with no network calls. Safe for internal data and tokens.

Why does my regex miss Korean characters?

In JS regex, the Hangul syllable range is \uAC00-\uD7A3. Mixed alphanumeric/Korean: [가-힣a-zA-Z0-9].

Can I alphabetize JSON keys?

Yes — JSON Key Sort. Nested objects sort too; array order is preserved.

Can I process very large text (10 MB+)?

The browser may stutter beyond 5–10 MB. For larger inputs use an IDE or dedicated tool.

Does the JWT decoder verify signatures?

It only decodes; it does NOT verify the signature. Use it to inspect payloads; verify on your server.

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