Popular & Trending Developer Tools
Our most frequently used utilities for CSS styling, regex debugging, JSON inspection, and security
Box Shadow Generator
Create custom multi-layered CSS box shadows with blur, spread, color, opacity, and inset controls.
CSS Gradient Generator
Design vibrant linear, radial, and conic CSS gradients with multi-stop color controls and export.
Regex Tester
Test and debug regular expressions with real-time match highlighting, group capturing, and flags.
JSON Viewer & Formatter
Format, validate, prettify, minify, and inspect JSON data hierarchies with interactive syntax trees.
Color Palette Generator
Generate beautiful harmonic color palettes from base colors or uploaded images with CSS export.
Password Strength Analyzer
Evaluate password security, calculate entropy bits, and identify vulnerabilities against brute force.
All 64 Developer Tools
Browse our complete directory of CSS generators, code formatters, security testers, and web design helpers
Box Shadow Generator
Create custom multi-layered CSS box shadows with blur, spread, color, opacity, and inset controls.
CSS Gradient Generator
Design vibrant linear, radial, and conic CSS gradients with multi-stop color controls and export.
Regex Tester
Test and debug regular expressions with real-time match highlighting, group capturing, and flags.
JSON Viewer & Formatter
Format, validate, prettify, minify, and inspect JSON data hierarchies with interactive syntax trees.
Color Palette Generator
Generate beautiful harmonic color palettes from base colors or uploaded images with CSS export.
Password Strength Analyzer
Evaluate password security, calculate entropy bits, and identify vulnerabilities against brute force.
Color Contrast Checker
Test WCAG 2.1 AA and AAA color contrast ratios between text and background colors for accessibility.
CSS Layout Generator
Visually generate CSS Grid and Flexbox multi-column layout code with gap and sizing controls.
SVG Optimizer
Minify and optimize SVG code by stripping metadata, unused tags, and comments in-browser.
Mock & Fake Data Generator
Generate realistic JSON, CSV, and SQL mock test data for frontend prototypes and database seeding.
Flexbox & Grid Builder
Build and test CSS flexbox containers and CSS grid systems with visual alignment controls.
Glassmorphism Generator
Generate frosted glass UI styles with real-time backdrop blur, transparency, and border CSS.
SVG Blob Generator
Create random organic SVG blob shapes and paths for modern website illustrations and headers.
SVG to CSS Converter
Transform SVG vector code into CSS data URI background images and inline SVG masks.
CSS Animation Builder
Design visual CSS keyframe animations with easing presets, duration sliders, and code export.
CSS Pattern Generator
Create pure CSS background patterns including grids, dots, geometric weaves, and stripes.
CSS Clamp Generator
Calculate fluid typography and responsive dimensions using CSS clamp() across viewport widths.
Case Converter
Convert naming conventions between camelCase, snake_case, kebab-case, PascalCase, and CONSTANT_CASE.
Password Helper & Generator
Generate cryptographically secure random passwords and memorable passphrases in-browser.
Password Entropy Calculator
Calculate bits of cryptographic entropy and cracking resistance for authentication security.
Git Command Explorer
Find the exact Git commands for complex version control tasks, branches, stashes, and history.
In-Browser Image Compressor
Compress JPEG, PNG, and WebP images locally with custom quality settings and file size previews.
EXIF Data Remover
Strip camera metadata, location coordinates, and timestamps from photos for complete privacy.
Image Redaction Tool
Blur, pixelate, or black out sensitive credentials, emails, and personal details on screenshots.
URL Cleaner & Untracker
Clean tracking tokens, UTM parameters, fbclid, and referral tags from URLs instantly.
Link Decompressor & Unshortener
Reveal true destinations of shortened URLs before opening them to avoid malware or phishing.
IPv4 Subnet Calculator
Calculate CIDR network blocks, subnet masks, usable host ranges, and broadcast addresses.
Contrast Grid Checker
Test color contrast across an entire multi-color design system palette against WCAG criteria.
Color Blindness Simulator
Preview how your UI colors look to people with Protanopia, Deuteranopia, and Tritanopia.
Photo Palette Extractor
Extract prominent color swatches and color palettes directly from uploaded image files.
Interactive Color Palette
Generate, lock, fine-tune, and export 5-color palettes with hex codes and CSS variables.
Color Palette Helper
Create balanced monochromatic, analogous, and complementary color schemes with ease.
Color Psychology Explainer
Learn about psychological associations, emotional resonance, and branding power of colors.
Font Pair Previewer
Compare and preview Google Font typography pairings side-by-side on realistic webpage components.
Font Style Analyzer
Inspect font metrics, weights, styles, and character glyph readability properties.
Typographic Scale Calculator
Generate harmonious modular typographic hierarchies with CSS variables and rem units.
Kerning Practice Game
Train your eye for letter-spacing and typography kerning balance with instant scoring.
Code Find & Replace
Quickly find and replace terms in code snippets with case-sensitivity and regex support.
Bulk File Renamer
Batch rename file names using prefixes, suffixes, incremental numbering, and pattern matching.
Text De-Stupidifier
Convert typographic quotes, curly apostrophes, and unusual Unicode characters to clean ASCII.
Fun Lorem Ipsum Generator
Generate entertaining placeholder text inspired by pirate, hipster, cyberpunk, and foodie themes.
Lorem Faux Obfuscator
Obfuscate confidential mockups and slides with stylized redacted text blocks.
Markdown to Slides
Convert standard Markdown documents into interactive browser presentation slide decks.
Aspect Ratio Calculator
Calculate proportional width and height scaling for responsive video, images, and displays.
A/B Test Significance
Calculate statistical confidence and conversion rate lift for growth experimentation.
Is It Down Checker
Check whether a website is experiencing downtime or network connection issues.
Website Carbon Footprint
Estimate carbon emissions per page load based on data transfer payload and host efficiency.
Spam Email Checker
Analyze newsletter text against spam filter trigger words to optimize email deliverability.
Domain Name Brainstormer
Generate creative domain name suggestions and TLD combos for projects and startups.
Fake Logo Generator
Create mock corporate logos with modern typography and geometric marks for UI wireframes.
Mockup Annotation Tool
Add markup notes, callout badges, and numbered annotations to UI design mockups.
3D Model Viewer
Inspect GLB, OBJ, and STL 3D models with 360-degree interactive camera orbit and lighting controls.
P2P File Transfer Demo
Direct device-to-device file transfer demo utilizing WebRTC peer data channels.
Cable Adapter Checker
Determine which adapters and converters connect USB-C, HDMI, DisplayPort, and Thunderbolt.
Can I Run It? Spec Checker
Evaluate hardware compatibility against minimum and recommended gaming system requirements.
Dark Pattern Quiz
Learn to recognize deceptive UI patterns like roach motels, sneak into basket, and confirmshaming.
Ethical Software Alternatives
Find privacy-respecting, open-source alternatives to proprietary big-tech SaaS software.
Open Source Software Finder
Discover high-quality open-source projects, tools, and developer libraries across ecosystems.
Public Domain Media Finder
Search for free, unrestricted public domain photography, video clips, and audio tracks.
Public Domain Image Styler
Apply artistic CSS duotone filters, vignettes, and texture overlays to vintage public domain art.
CC Video Clip Finder
Discover Creative Commons video footage for background headers, demos, and presentations.
Subreddit Discovery
Find active developer, programming, and web design communities on Reddit.
Learn to Code Roadmap
Step-by-step career roadmaps for frontend, backend, DevOps, and mobile software engineering.
Privacy Policy Generator
Generate a customized starter privacy policy for apps, browser extensions, and websites.
Why Choose Our In-Browser Developer Tools
Engineered with client-side web technologies for instant execution, complete privacy, and zero telemetry.
100% In-Browser Privacy
All regex evaluation, JSON parsing, password hashing, and image processing run locally on your machine. Zero code or tokens are ever sent to servers.
Instant Processing
Experience immediate real-time output and live previews with zero upload latency or remote queue delays.
Always Free & Open
Unlimited developer utilities with no subscriptions, no accounts, no credit card, and no rate limits.
Mobile & Desktop Ready
Carefully optimized responsive interface that works smoothly on smartphone browsers, tablets, and desktops.
Frequently Asked Questions
Everything you need to know about our free developer utilities, browser privacy, and supported features.
QAre all developer tools on Simple Online Tools completely free?
Yes, 100% of our 50+ developer utilities are completely free to use. There are no subscriptions, account registrations, API rate limits, or hidden paywalls.
QAre my code, regex, passwords, and JSON data kept private and secure?
Absolutely. Every developer utility executes purely inside your web browser using modern JavaScript, Canvas, and Web APIs. Your code snippets, passwords, test datasets, SVG files, and JSON payloads never leave your computer and are never sent to remote servers.
QWhat types of developer tools are available in this suite?
Our comprehensive suite includes CSS visual generators (Gradients, Box Shadows, Layouts, Animations, Patterns, Glassmorphism, Clamp), code helpers (JSON Viewer & Formatter, Regex Tester, Case Converter, Find & Replace), SVG vector tools (Optimizer, Blob Generator, SVG-to-CSS), color management (Palettes, WCAG Contrast Checkers, Color Blindness Simulation), mock data generators, and security tools (Password Strength & Entropy Analyzers).
QCan I use these developer tools on mobile devices and tablets?
Yes! All tools are built mobile-first with responsive interfaces optimized for quick lookups on smartphones, tablets, laptops, and wide desktop workstations.
QDo I need to install any npm packages, browser extensions, or dependencies?
No installation, build step, or configuration is required. Simply open any developer tool in your web browser and start building immediately.
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