Web Development Tools

Free utilities to build, test, format, and optimize HTML, CSS, JavaScript, and web data directly in your browser.

Available tools

CSS Gradient Generator

Create linear or radial CSS gradients with a live preview and copy the code.

CSS Border Radius Generator

Adjust every corner visually and copy a ready-to-use border-radius declaration.

Flexbox Playground

Explore Flexbox direction, alignment, distribution, wrapping, and gap visually.

CSS Grid Playground

Generate a CSS grid with configurable columns, rows, and gaps with an instant preview.

HEX RGB HSL Converter

Convert colors between HEX, RGB, and HSL with validation and an instant preview.

Online Color Picker

Choose a color visually, copy HEX, RGB, or HSL, and compare contrast with white and black.

HTML Formatter

Format HTML with consistent indentation through a parser and download the result locally.

Base64 Encoder and Decoder

Encode Unicode text to Base64 or decode it correctly through UTF-8.

URL Encoder and Decoder

Encode and decode URL components with percent encoding and Unicode support.

UUID Generator

Generate between 1 and 100 secure UUID v4 values locally through Web Crypto.

Online HTML CSS JavaScript Editor

Write HTML, CSS, and JavaScript and see the result in an isolated preview inside your browser.

JSON Formatter and Validator

Validate, format, or minify JSON locally, compare sizes, and download the result.

CSS Minifier

Minify CSS with a reliable parser, compare file size, and download the resulting .css file.

JavaScript Minifier

Minify modern JavaScript locally with syntax-aware parsing and download the .js file.

CSS Box Shadow Generator

Create a box-shadow visually, adjust every value, and copy ready-to-use CSS.

Regex Tester

Test regular expressions, flags, and matches against text directly in your browser.

Unix Timestamp Converter

Convert Unix timestamps in seconds or milliseconds to UTC and local dates, and back.

Meta Tag Generator

Create your page title, meta description, canonical URL, and search engine directives, then copy the ready-to-use HTML.

Open Graph Preview

Simulate an approximate social card and generate Open Graph tags without querying external platforms.

Markdown to HTML Converter

Convert Markdown to HTML with an isolated preview and support for headings, lists, links, and code.

HTML Entities Encoder and Decoder

Encode special characters as HTML entities or safely decode them back to text.

robots.txt Generator

Create Allow and Disallow rules and add a sitemap with clear technical warnings.

XML Sitemap Generator

Paste URLs and generate valid sitemap XML with escaping, lastmod, and duplicate detection.

Showing 123 of 23 tools

Utilities for code and web data

Formatters and minifiers serve different purposes: formatters make code easier to read and review, while minifiers remove unnecessary characters before publishing. You can also validate JSON, test regular expressions, and transform data with Base64 or URL encoding.

Playgrounds help check HTML, CSS, and JavaScript in isolation. Color and CSS tools generate practical values, although final results should still be tested in the browsers your project supports.

Technical SEO tools for developers

Meta tag, Open Graph, robots.txt, and sitemap.xml generators help prepare markup and files, but every result should be reviewed against the real structure and rules of the site before publishing.

When a tool states that processing is local, content is transformed in your browser and is not sent to Utilsha. Code previews remain isolated in a restricted iframe.