CSS & Frontend Tools Online - Free Developer Utilities

JSON to CSV Converter Transform nested or tabular JSON datasets into clean, spreadsheet-ready CSV files with custom delimiters and automatic key flattening.

Popular

CSV to JSON Converter Instantly convert CSV files and spreadsheet data into valid, nicely indented JSON structures for web APIs, testing, and databases.

Core Tool

JSON to YAML Converter Convert JSON payloads into clean, indented YAML format with strict indentation for Docker, Kubernetes, and cloud configs.

DevOps

YAML to JSON Converter Translate YAML configurations into strictly formatted JSON for API consumption, programmatic testing, and database ingestion.

DevOps

JSON Formatter & Beautifier Transform messy, unformatted, or minified JSON into clean, readable code with syntax validation and 1-click indentation options.

Top Tool

SQL Query Formatter & Beautifier Beautify messy, single-line SQL queries with structured indentation and standard uppercase SQL keywords (SELECT, FROM, WHERE, JOIN).

Database

Markdown to HTML Converter Compile Markdown text into clean, semantic HTML5 code with instantaneous browser rendering and 1-click HTML copy.

Content

Base64 Encoder & Decoder Encode strings into RFC 4648 Base64 representation or decode Base64 payloads back to readable UTF-8 text.

Standard

URL Encoder & Decoder Safely encode special characters into percent-encoded (%20, %26) URI components or decode encoded URLs back to human-readable strings.

Web Standard

PX to REM Converter & Cheat Sheet Convert PX to REM and REM to PX in real-time with customizable base font size (16px default) and comprehensive typography reference tables.

High Search Vol

CSS clamp() Calculator for Fluid Typography Generate fluid, responsive font sizes and spacing that scale smoothly across mobile and desktop screens without media query breakpoints.

Modern CSS

Aspect Ratio Calculator (16:9, 4:3, 21:9) Calculate matching dimensions, aspect ratio fractions, and CSS aspect-ratio properties with instant presets for popular device resolutions.

Essential

CSS Box Shadow Generator Design multi-layered CSS box shadows visually with real-time preview, opacity sliders, blur spread controls, and 1-click CSS code export.

Interactive UI

CSS Glassmorphism & Frosted Glass Generator Design sleek frosted glass UI elements with adjustable backdrop-filter blur, background opacity, outline highlights, and instant CSS export.

Trending UI

CSS Gradient Generator (Linear & Radial) Create multi-color linear and radial gradients with real-time canvas preview, custom angle rotation, and production-ready CSS rules.

Design

SEO Meta Tag & Open Graph Generator Create complete SEO meta tags, Open Graph tags, and Twitter Cards with character limit indicators to maximize your Google rankings and social CTR.

SEO Core

Robots.txt File Generator Generate clean robots.txt directives to guide search engine web crawlers, protect private directories, and declare XML sitemaps.

Crawl Control

.htaccess 301 Redirect & Security Generator Create tested Apache mod_rewrite directives: enforce HTTPS, consolidate canonical domains (www vs non-www), and set up permanent 301 redirects.

Apache

HTML Minifier & Compressor Strip unnecessary whitespace, redundant comments, and line breaks from HTML documents to boost page speed and lower bandwidth consumption.

PageSpeed

SHA-256 Hash Generator Compute 256-bit (64 hex characters) cryptographic hash checksums for any input string using browser-native Web Crypto APIs.

Cryptography

MD5 Hash Checksum Generator Calculate 32-character hexadecimal MD5 hash checksums for cache busting, database keys, and file integrity verification.

Checksum

Strong Password Generator & Entropy Checker Create cryptographically secure, high-entropy passwords and API secret keys using the Web Cryptography API random number generator.

Security

UUID v4 Generator (Single & Bulk) Generate standard RFC 4122 compliant version 4 UUIDs (Universally Unique Identifiers) for database primary keys, distributed systems, and API tracking.

RFC 4122

JWT (JSON Web Token) Debugger & Inspector Decode Base64Url encoded JWTs to inspect authentication headers, payload claims (iss, sub, exp), and verify token expiration in real-time.

API Security

Word, Character & Sentence Counter Calculate real-time text metrics: word count, characters, sentences, paragraphs, reading time, and estimated speaking duration.

Essential

String Case Converter (camelCase, snake_case, Title Case) Transform variable names, article headlines, and code identifiers between camelCase, snake_case, kebab-case, UPPERCASE, and Title Case.

Popular

URL Slug Generator (SEO Slugify) Transform blog post titles and page headings into clean, lowercase, hyphenated URL slugs optimized for search engine indexing.

SEO Core

Lorem Ipsum Dummy Text Generator Generate standard Cicero dummy placeholder text for website wireframes, UI mockups, and typography testing with custom paragraph counts.

Design

Duplicate Line Remover & Text Sorter Clean up email lists, keyword lists, and data exports by stripping duplicate entries, trimming extra spaces, and sorting alphabetically.

Utility

REM to PX Converter Convert REM units back to pixel dimensions with customizable root font sizes (16px default) for CSS layout development.

CSS3

HEX to RGB & HSL Color Converter Convert web colors across HEX (#3b82f6), RGB (rgb(59, 130, 246)), and HSL formats with interactive color preview and 1-click CSS copying.

Design

CSS Minifier & Optimizer Compress CSS stylesheets by stripping comments, spaces, and line breaks to minimize render-blocking stylesheet latency.

Performance

JavaScript Minifier & Code Compressor Compress JavaScript files safely by stripping multi-line and single-line comments, superfluous spaces, and newline characters.

Performance

SHA-512 Cryptographic Hash Generator Compute 512-bit (128 hexadecimal characters) SHA-2 family hashes for mission-critical checksums, blockchain verification, and token verification.

High Security

Text Diff Checker (Side-by-Side Compare) Compare two versions of code, configuration files, or documents side-by-side to highlight additions, deletions, and line modifications.

Developer Tool

HTML to Markdown Converter Convert raw HTML documents and CMS rich text into clean Markdown syntax for static site generators (Astro, Hugo, Jekyll) and documentation.

Content Migration

User Agent String Parser & Client Inspector Parse HTTP User-Agent header strings to identify browser names, software versions, operating systems, and device form factors.

Network Info

JSON to TypeScript Interface Generator Instantly transform raw JSON payloads into clean, idiomatic TypeScript interfaces and types for front-end React, Vue, and Node.js codebases.

TypeScript

Unix Timestamp & Epoch Converter Convert between Unix timestamps (seconds & milliseconds) and human-readable UTC/local date formats with live current timestamp counter.

Time Utility

Free QR Code Generator Online Create high-resolution QR codes for website URLs, contact info, and text strings. Custom sizes and immediate 1-click PNG image download.

Marketing

WCAG Color Contrast Ratio Checker Verify text and background color combinations against Web Content Accessibility Guidelines (WCAG 2.1) for Level AA and Level AAA compliance.

WCAG 2.1

Harmonious Color Palette Generator Create balanced design color palettes from any base HEX color: complementary, analogous, triadic, and monochromatic schemes with 1-click CSS copying.

Design System

HTML Entity Encoder & Decoder Safely escape reserved HTML characters (<, >, &, ", ') into named or numeric entities to prevent XSS vulnerabilities and rendering glitches.

Web Standard

SVG Code Cleaner & Optimizer Strip XML metadata, Illustrator/Figma export junk, and superfluous namespaces from SVGs to optimize asset payload weight for high Core Web Vitals.

Performance

CSS Pure Triangle Generator Design pure CSS triangles using transparent border geometry with custom direction, dimensions, color picker, and 1-click CSS export.

CSS Shapes

cURL to JavaScript Fetch & Python Converter Transform raw cURL command lines into clean, production-ready JavaScript fetch(), Python requests, or Axios API call snippets.

High Intent

HTML to React JSX & TSX Converter Transform raw HTML5 markup into compliant React JSX/TSX syntax: auto-replaces class with className, for with htmlFor, and self-closes tags.

React & Next.js

CSS Grid Layout Generator Design complex CSS grid structures with custom column/row counts and gaps. Preview your layout in real time and copy ready-to-use CSS rules.

Visual Builder

CSS Flexbox Playground & Generator Experiment with modern CSS Flexible Box properties visually. Tweak alignments, wrapping, and spacing with instant live preview and 1-click CSS export.

Interactive

Online Regex Tester & Debugger Evaluate regex patterns against sample text in real time with visual match highlighting, capture group breakdown, and ready-to-use common pattern presets.

High Traffic

Bcrypt Hash Generator & Verifier Create salted Bcrypt password hashes and test password matches against existing hashes locally in your browser with zero network exposure.

Backend Security

JSON to JSON Schema Converter Auto-generate structured draft-07 compliant JSON Schema definitions from any JSON input with type inference and automatic required properties.

API Tools

URL Parser & Query String Editor Dissect any web URL into its fundamental protocol, hostname, path, and query parameters. Edit or add parameters in a table and rebuild updated URLs instantly.

Developer Utility

Markdown Table Generator & Editor Create and edit structured Markdown tables with an interactive GUI table builder. Supports column alignment and instant 1-click Markdown copying.

Documentation

Cron Expression Generator & Explainer Generate valid crontab schedule expressions with visual interval controls and instant human-readable English translation for Linux and cloud schedulers.

DevOps & Cloud

Campaign URL Builder & UTM Generator Construct validated marketing campaign URLs with proper UTM parameters for GA4, newsletters, social media, and paid ads with instant 1-click copy.

SEO & Growth

CIDR Subnet Calculator & IPv4 Range Finder Instantly calculate network netmasks, broadcast addresses, usable IP address ranges, and total host capacities from any IP and CIDR prefix.

DevOps & Network

Tailwind CSS Color Palette Generator Pick any base HEX color and automatically generate a balanced 10-shade palette (50, 100, 200, 300, 400, 500, 600, 700, 800, 900, 950) for your Tailwind UI.

Frontend UI

Image to Base64 & Data URI Converter Drop or select PNG, JPG, WebP, or SVG files to instantly encode them into Base64 Data URIs, HTML image tags, and CSS background rules without uploading.

100% Private

Mock API Data & Fake JSON Generator Generate realistic placeholder JSON datasets with customizable record counts for prototyping frontend interfaces and testing API workflows.

API Mocking

Visual HTML Table Generator Build and customize structured HTML tables visually. Tweak table cells, headers, and alignments with instant 1-click semantic HTML export.

Webmaster Tool

JSON Diff & Comparison Tool Perform side-by-side structural comparison of two JSON payloads. Highlights modified, added, and deleted properties with zero server logging.

Debugging

Open Graph & Social Share Preview Generator Simulate social media share cards for Twitter, Facebook, and LinkedIn in real time. Validate image ratios and export ready-to-paste meta tags.

Social SEO

JSON-LD Schema Markup Generator Generate structured schema.org markup in JSON-LD format to qualify for Google rich search results, review stars, and FAQ accordion snippets.

Rich Snippets

Google SERP Snippet Simulator & Pixel Calculator Preview and optimize how your pages appear on Google search results. Real-time title pixel width warnings, mobile/desktop toggle, and rich star ratings.

SERP Preview

cURL to Python Requests Converter Convert raw cURL shell commands into production-ready Python code using the requests library. Supports authentication, headers, and JSON payloads.

API & Code

HMAC Hash & Signature Generator Generate cryptographic HMAC signatures with custom secret keys using the browser's hardware-accelerated WebCrypto API. Zero data transmitted over the network.

Webhooks & Crypto

XML to JSON Converter Parse and convert XML data into structured, indented JSON with zero server latency. Preserves tags, values, and attributes client-side.

XML & JSON

8-Value CSS Border Radius Generator Create organic blob shapes and custom corner curvatures using 8-value border-radius syntax. Visual sliders with instant copy-paste CSS.

Organic Shapes

CSS Text Shadow Generator Build multi-layered, striking CSS text shadows with real-time typography preview. Adjust horizontal/vertical offsets, blur radius, and shadow color.

Typography

JSON Path Finder & Tree Inspector Inspect and navigate nested JSON structures interactively. Click any key to copy its exact dot notation or JSONPath query directly to clipboard.

API Inspection

ASCII Text to Hex, Binary & Decimal Converter Convert plain text into binary (01010011...), hexadecimal (53 65 63...), decimal, and octal encodings with instant 1-click copy.

Binary & Hex

SQL to JSON Converter Convert SQL INSERT statements and database table dumps into structured JSON arrays. Automatically infers numbers, strings, and booleans.

DB Migration

JSON to XML Converter Transform complex JSON payloads and arrays into clean, indented XML documents. Supports root element naming and nested structures.

Data Serialization

TSV to JSON Converter Convert tab-delimited text copied directly from Microsoft Excel or Google Sheets into structured JSON arrays of objects.

Excel & Sheets

CSS Neumorphism (Soft UI) Generator Design tactile Soft UI components with dual light and dark shadow physics. Sliders for elevation, blur, radius, and shape curvature.

Soft UI

Color Tints & Shades Generator Produce an entire ramp of tints (white mixed) and shades (black mixed) from any brand color. Includes 1-click copy and WCAG contrast ratings.

Palettes & WCAG

HTML Entity Decoder & Encoder Convert between HTML entities (named, decimal, hexadecimal) and literal characters with bidirectional instant conversion.

Encodings

Lorem Ipsum Markdown Generator Generate structured dummy Markdown documents with realistic headings, checklists, code blocks, tables, and blockquotes for SSG and doc testing.

Documentation

User-Agent Generator & Header Library Search, filter, and copy authentic User-Agent strings for desktop browsers, mobile devices, tablets, and search engine crawlers with 1-click copy.

Scraping & QA

Cron Expression Descriptor & Human Explainer Convert standard 5-part crontab schedule expressions into clear, plain English descriptions with upcoming execution timestamps.

Automation

Mock JSON API Generator & Dummy Data Instant mock JSON array generator with realistic user profiles, e-commerce products, financial orders, and ISO timestamps for API mocking.

API Mock

CSS Clip-Path Shape Generator Design geometric clip-path shapes including polygons, stars, hexagons, arrows, and speech bubbles with instant CSS code export.

Polygons & Shapes

SVG to Data URI Converter & CSS Inliner Instantly encode raw SVG vector code into compact, URL-encoded Data URIs ready for CSS background-image and HTML tags.

Vector & CSS

Timestamp Difference & Duration Calculator Calculate precise duration, days, hours, minutes, and working business days between two timestamps, epochs, or dates.

Time & Date

Meta Tags & Social Snippet Analyzer Paste any HTML snippet or meta tags to analyze title lengths, meta descriptions, Open Graph cards, canonical tags, and SERP health.

SERP & Social

Linux Chmod Permissions Calculator Interactive 3x3 permission grid for Owner, Group, and Others. Instantly computes numeric octal masks, symbolic notation, SUID/SGID bits, and terminal commands.

Sysadmin

IP Range to CIDR Subnet Calculator Calculate the minimal set of CIDR subnet blocks covering any IP address range (IPv4). Ideal for cloud security groups, AWS VPC, UFW, and routing tables.

Network & Cloud

CSS Keyframes Animation Generator Create smooth CSS @keyframes animations with interactive presets, timing functions, durations, iterations, and 1-click ready-to-paste CSS rules.

UI & Motion

Base64 to Image Decoder & Previewer Paste any Base64 encoded string or image Data URI to instantly decode, inspect width/height and file size, and download the original PNG, JPG, WebP, or SVG file.

Decoder

Online DNS Record Lookup & Inspector Lookup and audit DNS records across A, AAAA, MX, TXT, CNAME, NS, and SOA using high-speed DNS-over-HTTPS (DoH).

DoH Live

HTTP Security Headers Analyzer & Auditor Analyze raw server response headers, detect missing security policies (HSTS, CSP, X-Frame-Options, Permissions-Policy), and export ready-to-paste Nginx and Apache configs.

Auditor

UUID v7 & v4 Generator & Timestamp Inspector Generate time-ordered, B-Tree index-friendly UUID v7 identifiers based on RFC 9562. Decode embedded millisecond timestamps and inspect versions.

RFC 9562

SVG Path Visualizer & Bounds Inspector Paste any SVG path data attribute to render interactive vector outlines, inspect total path length, bounding dimensions, and coordinate commands.

Vector UI

HTML Table to Markdown & CSV Converter Transform raw HTML tables into clean, aligned GitHub Flavored Markdown (GFM) tables and spreadsheet-ready CSV with 1-click copy.

Markdown

Image EXIF Metadata Stripper & Privacy Cleaner Protect personal privacy by inspecting and stripping hidden EXIF metadata, GPS latitude/longitude, and camera models from photos before publishing online.

Privacy Tool

HTTP Archive (HAR) Analyzer & Performance Waterfall Upload or paste browser DevTools network .har export files to analyze page load waterfalls, request counts, transfer weights, and HTTP status codes.

DevOps & CWV

TOML to JSON & YAML Converter Transform Tom's Obvious Minimal Language (TOML) files into clean, formatted JSON or YAML with instant client-side parsing and 1-click copy.

Configuration

CSS Hex to Color Filter Converter Calculate the exact CSS filter rules needed to transform a black (#000000) SVG icon or image into any custom target Hex, RGB, or HSL color.

Vector UI

Content Security Policy (CSP) Generator & Validator Build robust Content-Security-Policy headers with interactive directive toggles, third-party service presets (GTM, AdSense, Stripe), and real-time security analysis.

XSS Defense

View All Cheat Sheets Hub 32+ Matrices

Git Commands Reference Matrix 40+ Cmds

Docker & Docker Compose Cheat Sheet 35+ Cmds

Kubernetes & Kubectl Cheat Sheet 35+ Cmds

Linux Terminal & Sysadmin Matrix Top 50

Bash Scripting Commands & Syntax 30+ Recipes

SSH & Remote Admin Commands 25+ Recipes

Vim & Neovim Editor Commands 40+ Cmds

Regular Expressions (Regex) Cheat Sheet 35+ Patterns

Cron Job Schedule Expressions Matrix 25+ Recipes

SQL Query & Database Cheat Sheet 30+ Queries

Python 3 Programming Commands 35+ Recipes

Markdown & GFM Syntax Cheat Sheet 25+ Rules

HTTP Status Codes & Server Fixes 21 Codes

Common Network Ports & Firewall Rules 20+ Ports

Tmux Commands & Terminal Multiplexer 35+ Shortcuts

cURL CLI Recipes & API Cheat Sheet 35+ Recipes

PostgreSQL CLI (psql) & Administration 30+ Commands

Nginx Configuration & Server Snippets 25+ Configs

MongoDB & Mongosh Queries Matrix 30+ Commands

Redis CLI & In-Memory Data Store 30+ Commands

Systemd, Systemctl & Journalctl Matrix 25+ Commands

AWS CLI Cloud Infrastructure Matrix 25+ Commands

GitHub Actions Workflow & CI/CD Matrix 25+ Rules

GraphQL Query, Mutation & Schema Matrix 25+ Queries

Apache .htaccess Configuration Matrix 25+ Rules

Helm Kubernetes Package Manager Matrix 20+ Commands

Terraform & OpenTofu CLI Commands Matrix 30+ Commands

Iptables & Netfilter Firewall Commands Matrix 25+ Rules

Ansible CLI & Playbook Commands Matrix 20+ Commands

Conventional Commits & SemVer Matrix 20+ Syntax Rules

Sed & Awk Text Processing Matrix 20+ Commands

gRPC & Protocol Buffers Matrix 20+ Commands