Toolsly

Category

Dev

Code formatters, minifiers, beautifiers — HTML, CSS, JS, SQL, XML, YAML.

29 free dev tools — no sign-up, runs in your browser.

DevParser

URL Parser

Break a URL into its components — protocol, host, port, path, query parameters, hash — with each query param listed individually.

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DevParser

User-Agent Parser

Parse a browser User-Agent string into structured browser/engine/OS/device fields.

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DevReference

HTTP Status Code Lookup

Look up any HTTP status code — title, category, RFC explanation, and the situations it's actually used for.

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DevReference

MIME Type Lookup

Look up the MIME type for a file extension, or the canonical extensions for a MIME type — covering 100+ common types.

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DevCalculator

IPv4 Subnet Calculator

Calculate network/broadcast addresses, host range, mask, wildcard mask, host counts, and IP class from a CIDR.

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DevMinifier

CSS Minifier

Minify CSS — strip whitespace, comments and unused syntax to ship smaller stylesheets.

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DevBeautifier

CSS Beautifier

Pretty-print CSS — choose 2-space, 4-space or tab indentation for readable stylesheets.

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DevMinifier

HTML Minifier

Minify HTML — collapse whitespace, drop comments and optionally compress inline JS and CSS.

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DevBeautifier

HTML Beautifier

Pretty-print HTML — readable indentation with nested tags on their own lines.

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DevMinifier

JavaScript Minifier

Minify JavaScript with Terser — compress, mangle and ship the smallest possible bundle.

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DevBeautifier

JavaScript Beautifier

Pretty-print JavaScript — consistent indentation and one statement per line for readable code.

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DevFormatter

SQL Formatter

Format SQL queries for every major dialect — Postgres, MySQL, SQLite, BigQuery, Snowflake and more.

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DevFormatter

XML Formatter

Pretty-print XML documents — indent nested tags with 2 or 4 spaces for readable markup.

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DevFormatter

YAML Formatter

Reformat YAML — normalize indentation, line wrapping and quoting for tidy config files.

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DevValidator

CSV Validator

Validate CSV data — check column consistency, count rows and surface parse errors.

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DevConverter

PX to REM Converter

Convert between px, rem and em based on a root font size — instant CSS-ready values, in-browser.

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DevGenerator

Type Scale Generator

Build a modular typographic scale from a base size and ratio — px, rem and CSS variables, in-browser.

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DevCalculator

Line Height Calculator

Resolve any CSS line-height (unitless, px or %) to its computed pixel height and ratio — in-browser.

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DevMinifier

SVG Minifier

Minify SVG markup — strip comments, declarations and whitespace to shrink file size, all in your browser.

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DevConverter

Htaccess to Nginx Converter

Convert Apache .htaccess rewrite rules and directives to nginx configuration — free, in your browser.

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DevReference

Regex Cheat Sheet

Interactive regex reference — anchors, quantifiers, groups, character classes, lookaround, and flags with examples.

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DevValidator

JSON Validator & Formatter

Validate JSON and see errors with line numbers — plus auto-format/beautify. Free, instant, in-browser.

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DevCalculator

Chmod Calculator

Convert between numeric (755) and symbolic (rwxr-xr-x) Unix file permissions. Free, instant, in-browser.

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DevGenerator

Meta Tag Generator

Generate HTML meta tags for SEO, Open Graph, and Twitter Cards. Free, instant, copy-paste ready.

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DevBuilder

CSP Header Builder

Build a Content-Security-Policy header interactively — select policies for each directive and get the full header string.

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DevSEO

Robots.txt Tester

Test whether a URL path is allowed or blocked by robots.txt rules for a specific crawler.

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DevSEO

Hreflang Tag Generator

Generate hreflang alternate link tags from language codes and localized URLs.

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DevLookup

Instagram ID Finder

Find the numeric Instagram user ID for a public profile URL or username.

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DevLookup

Facebook ID Finder

Find the numeric Facebook profile or page ID from a public URL, username, or ID link.

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Frequently asked

Are Toolsly developer tools free?

Yes. Formatters, minifiers, beautifiers, and validators for HTML, CSS, JS, SQL, XML, YAML, and JSON are all free.

Do these tools run offline?

Yes. All developer tools on Toolsly are client-side, so once the page is loaded they work without a network connection.

Can I use these in a script or CI?

Toolsly is a UI for one-off transformations. For scripting, the underlying libraries (Prettier, esbuild, jsbeautify, etc.) are open source and run in Node.