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Text & Developer Tools

The largest hub on the site: counting and case conversion for writing, diff and find-replace for editing, formatters and converters for JSON, YAML, XML and CSV, plus regex testing, hashing, encoding and a JWT decoder. Everything executes in the page, so you can paste real data without it leaving the tab.

Word & Character Counter

Count words, characters, sentences, paragraphs and lines instantly. Runs entirely in your browser — your text never leaves your device.

Private · in-browser

Case Converter

Convert text between UPPERCASE, lowercase, Title Case, camelCase, snake_case, kebab-case and more — instantly in your browser.

Private · in-browser

Slug Generator

Turn any title into a clean, URL-friendly slug. Removes accents and punctuation; runs in your browser.

Private · in-browser

Text Reverser

Reverse any string character by character. Handles Unicode correctly; runs locally.

Private · in-browser

Remove Duplicate Lines

Strip duplicate lines from a list, keeping the first occurrence. Optional case-insensitive and trim modes.

Private · in-browser

Sort Lines

Sort lines alphabetically, ascending or descending, with optional case-insensitive comparison.

Private · in-browser

Number Base Converter

Convert numbers between binary, octal, decimal and hexadecimal (or any base 2–36).

Private · in-browser

Roman Numeral Converter

Convert numbers to Roman numerals and back (1–3999), instantly in your browser.

Private · in-browser

Base64 Encode / Decode

Encode text to Base64 or decode Base64 back to text (UTF-8 safe), entirely in your browser.

Private · in-browser

URL Encode / Decode

Percent-encode text for safe use in URLs, or decode encoded URLs back to text.

Private · in-browser

HTML Encode / Decode

Escape HTML special characters (&, <, >, ", ') or decode entities back to text.

Private · in-browser

Epoch / Unix Timestamp Converter

Convert Unix timestamps (seconds or milliseconds) to human-readable UTC dates and back.

Private · in-browser

JWT Decoder

Decode a JSON Web Token to inspect its header and payload. Decoding only — no verification, all in your browser.

Private · in-browser

JSON Formatter & Validator

Pretty-print, minify and validate JSON with clear error messages — entirely in your browser.

Private · in-browser

JSON ↔ CSV Converter

Convert between JSON arrays and CSV in your browser. Handles nested keys and quoting.

Private · in-browser

XML Formatter

Pretty-print and indent XML for readability, locally in your browser.

Private · in-browser

YAML ↔ JSON Converter

Convert YAML to JSON and back, right in your browser.

Private · in-browser

Diff Checker

Compare two blocks of text and highlight the differences line by line.

Private · in-browser

Regex Tester

Test regular expressions against sample text with live match highlighting and flags.

Private · in-browser

Lorem Ipsum Generator

Generate placeholder lorem ipsum text by words, sentences or paragraphs.

Private · in-browser

Hash Generator (SHA-1 / SHA-256 / SHA-384 / SHA-512)

Generate cryptographic hashes of text using the browser’s Web Crypto API. Nothing is uploaded.

Private · in-browser

Markdown Preview

Write Markdown and see a live HTML preview, rendered safely in your browser.

Private · in-browser

Find & Replace

Find and replace text with optional case-insensitive and regex modes, all in your browser.

Private · in-browser

Cron Expression Parser

Explain a cron expression in plain English and preview its schedule.

Private · in-browser

UUID Generator

Generate random v4 UUIDs in your browser, one or many at a time.

Private · in-browser

Which tool do I need?

Twenty-five tools is a lot to scan, so group them by the job in front of you.

Three distinctions worth being precise about

Decoding a JWT is not verifying it. The header and payload are only Base64url text, so anyone can read them and anyone can forge them. Only the signature check proves a token is authentic, and that needs the signing key on a server. Treat a decoded payload as a debugging aid, never as an authorization decision.

Hashing is not encryption. SHA-256 is one-way: there is no key and no decrypt step, which is exactly why it works for checksums and integrity checks. Note that Web Crypto offers SHA-1, SHA-256, SHA-384 and SHA-512 but no MD5, and that SHA-1 has been practically collision-broken since 2017 — fine for spotting accidental corruption, unfit for any security decision.

Base64 is not protection either. It is a transport encoding for systems that mangle binary or non-ASCII bytes. Anyone can decode it in one step, so never use it to hide a credential.

Why these run in the browser

Developer utilities get pasted full of production payloads, API responses and tokens. Every tool here works in JavaScript on your machine — no request carries your text anywhere, so pasting a real response body is not a disclosure.

Frequently asked questions

Does the JWT decoder verify the token signature?
No. It splits the token and Base64url-decodes the header and payload so you can read the claims. Verification requires the secret or public key that signed it, which belongs on a server. A token that decodes cleanly here can still be expired, tampered with, or entirely fabricated.
Is a hash the same as an encrypted version of my text?
No. Encryption is reversible with a key; a hash is a one-way fingerprint with no key and no way back. That is what makes hashes useful for verifying that a file or string is unchanged, and useless for storing something you need to read again later.
Which regex flavor does the tester use?
JavaScript (ECMAScript), executed by your browser’s own RegExp engine, so behavior matches frontend code and Node exactly. Most PCRE syntax carries over, but PCRE-only features such as atomic groups and possessive quantifiers are unavailable. Enter the pattern raw, without surrounding slashes or quotes.
Why is there no MD5 option in the hash generator?
The browser’s Web Crypto API deliberately omits MD5, which has been collision-broken since 2004, and the tool uses that API rather than shipping its own crypto. For new work publish SHA-256 instead; to check a legacy MD5 checksum, use a local command-line utility such as md5sum.
Case converter or slug generator — which one do I want for a URL?
The slug generator. It strips accents and punctuation, lowercases, and joins words with hyphens, so a title becomes a safe URL segment. The case converter changes capitalization style, including kebab-case, but it leaves characters like accented letters in place, so kebab-case output is not necessarily URL-safe.