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Developer Tools

Use this group to read or tidy code and color values. These pages do not run a site and they do not publish anything.

Format HTML, CSS, JavaScript, or JSON when a paste is hard to read. Minify only when you want a shorter copy of text you already trust. The JavaScript formatter does not execute the script. The JSON tree lists keys. The live preview and the playground run what you paste inside the page. Treat that as your own code, not a hosting service.

Color tools convert HEX, RGB, and HSL, mix two colors, or build a gradient, a shadow, a radius, or a clip shape. The clip preview does not cut a file. Encoding tools turn text into URL encoding, HTML entities, or Base64. A JWT inspector shows the header and payload. It does not check the signature and it does not decrypt a secret.

A photo of a screen is still an image. Use Image and Photo for that file. Open Graph tags here are text you copy into a page. They do not upload an image.

Tools in this group

HTML Live Preview

Paste HTML/CSS/JS and preview the page instantly — runs in your browser.

Developer Tools In the browser

HTML/CSS/JS Playground

Mini CodePen: three panels plus live sandboxed preview.

Developer Tools In the browser

Markdown Preview

Write Markdown and get clean HTML preview — all local.

Developer Tools In the browser

HTML Beautify / Minify

Pretty-print or minify HTML in your browser.

Developer Tools In the browser

CSS Beautify / Minify

Pretty-print or minify CSS in your browser.

Developer Tools In the browser

JSON Formatter

Pretty-print or minify JSON safely in-browser.

Developer Tools In the browser

URL Encoder / Decoder

Encode or decode URL strings (encodeURIComponent and friends).

Developer Tools In the browser

Base64 & URL Encode

Encode or decode Base64 and URL strings.

Developer Tools In the browser

Read a JWT

Decode a token header and payload. The signature is not checked.

Developer Tools In the browser

HTML entities

Encode or decode HTML characters. The result is text, not a live page.

Developer Tools In the browser

Image to data URL

Turn a small image into a data URL. The limit is 2 MB.

Developer Tools In the browser

JSON tree

Show a JSON value as nested keys.

Developer Tools In the browser

JavaScript formatter

Indent braces or strip spare space. It does not run the script.

Developer Tools In the browser

Open Graph tags

Write title, description, and HTTPS tags you copy into the page head.

Developer Tools In the browser

Code to image

Draw up to 40 lines of code as a PNG. The code is not run.

Developer Tools In the browser

Unix timestamp

Convert Unix seconds to a date, or a date to Unix seconds.

Developer Tools In the browser

Base64 to image

Decode an image data URL or Base64 string and download it.

Developer Tools In the browser

cURL Command Generator

Build a correctly quoted curl command (Bash, PowerShell or Windows cmd) and the matching JavaScript fetch() code for any HTTP request.

Developer Tools In the browser

User-Agent Parser

Read any user-agent string: browser and version, engine, operating system, device type and known bots and crawlers.

Developer Tools In the browser

Page Source Viewer

View and download the raw HTML a server returns for any public URL, with size, line count and all response headers.

Developer Tools Server processing

Data Converter (JSON, CSV, XML, YAML, TSV, TOML)

Convert between JSON, CSV, TSV, XML, YAML, TOML, plain lists and Markdown tables — with headers, type detection and nested data flattened for spreadsheets.

Developer Tools In the browser

XML / YAML / TOML / SQL Formatter & Validator

Pretty-print, minify or check XML, YAML, TOML and SQL — with the exact line and column of the first error.

Developer Tools In the browser

Validate Email, URL, IP, UUID, MAC & Domain

Check a whole list at once: each line is detected or checked as email, URL, IPv4/IPv6, UUID, MAC address or domain, with the reason when it fails.

Developer Tools In the browser

Regex Tester

Test a JavaScript regular expression against your text: highlighted matches, positions and capture groups, plus replace and split previews — with a hard time limit.

Developer Tools In the browser

URL Parser & Cleaner

Break a URL into its parts and parameters, strip tracking tags (utm_, gclid, fbclid…), resolve relative links, sort query parameters and make encoded URLs readable.

Developer Tools In the browser

Unicode Converter (code points, UTF-8/16/32)

Turn text into Unicode code points, UTF-8 / UTF-16 / UTF-32 units, or HTML, CSS, JavaScript and Python escapes — and back. Inspect every character’s category and script.

Developer Tools In the browser

Text ↔ Binary / Hex Converter

Convert text to binary, hexadecimal, octal or decimal bytes (UTF-8, UTF-16 or Latin-1) and decode bytes back into readable text.

Developer Tools In the browser

Base32 / Base58 / Base85 Encoder & Decoder

Encode text to Base32 (RFC 4648 and base32hex), Base45 (RFC 9285, used in QR health codes), Base58 (Bitcoin alphabet) or Ascii85 — and decode them back.

Developer Tools In the browser

Punycode / IDN Converter

Convert international domain names such as münchen.de or مثال.إختبار to their xn-- form and back — also inside email addresses and URLs.

Developer Tools In the browser

Cron Expression Parser

Paste a cron schedule (5 fields or @daily-style macros) and see what each field means and the next run times in your time zone.

Developer Tools In the browser

Cron Expression Generator

Build a cron schedule from plain choices — every N minutes, daily, weekdays, weekly, monthly or yearly at a time — and check the next run times before you deploy it.

Developer Tools In the browser

Random Test Data Generator (JSON, CSV, XML, SQL…)

Generate fake records for testing — names, example emails, fictional phone numbers, cities, dates, numbers, UUIDs, IPs, colours — as JSON, CSV, TSV, XML, YAML, NDJSON or SQL INSERTs.

Developer Tools In the browser

Other groups

Document & Scan · Image & Photo · PDF · Text & OCR · Creator / Social Utilities · CSS & Design · Color Tools · QR & Barcode · Security & Encoding · Utilities