Dev Tools

Small everyday tools. Everything runs in your browser — nothing is uploaded.

Encoding

64

Base64 Encode / Decode

Text, hex and files. URL-safe alphabet, padding, line wrap, data URIs. Decoded images are previewed.

 %

URL Encode / Decode

Percent-encode as a component, RFC 3986, form data or a full URL. Breaks a URL into parts and query parameters.

 &

HTML Entities

Encode and decode & < é and named entities.

 \n

String Escape / Unescape

Escape strings for JSON, JavaScript, Java, Python, SQL, regex, shell and CSV.

 JWT

JWT Decoder

Read a token’s header and claims, see when it expires, and check an HMAC signature.

Text & data

{}

JSON Viewer

Validate, format and minify. Collapsible tree, search, paths, exact big numbers and precise error locations.

 ±

Text Diff

Compare two texts side by side or unified, with word-level highlights.

 Aa

Case Converter

camelCase, snake_case, kebab-case, PascalCase, CONSTANT_CASE and more, all at once.

 Li

Lorem Ipsum

Placeholder paragraphs, sentences or words as plain text or HTML.

Generators

ID

UUID Generator

UUID v4 and time-ordered v7 in bulk, plus a validator that reads a UUID’s version and time.

 #

Hash Generator

MD5, SHA-1, SHA-256/384/512 and HMAC for text or files.

 ***

Password Generator

Strong random passwords and passphrases with an entropy meter.

 RSA

RSA Key Generator

2048–4096-bit key pairs as PEM (PKCS#8 or PKCS#1), OpenSSH or JWK, with the SHA-256 fingerprint.

Time & numbers

t

Unix Timestamp

Epoch seconds or milliseconds ↔ dates in UTC, local time and any time zone.

 *

Cron Explainer

Cron expressions in plain English, with the next run times.

 0x

Number Base Converter

Binary, octal, decimal, hex and any base 2–36, with two’s complement.

More: Algorithm & Systems Visualizations — interactive animations of algorithms, data structures and systems.