Developer Tools & Utilities
Accelerate your workflow with instant browser-based coding tools. Format JSON, debug API endpoints, validate regular expressions, generate configurations, and inspect network records with client-side privacy.
YAML to JSON Converter
Convert YAML to JSON with real-time validation and syntax highlighting
Iframe Generator
Generate responsive, secure iframe embed code with sandbox flags and preview
Box Shadow Generator
Create multi-layer CSS box-shadows with presets, inset support, and live preview
3 Digit Random Number Generator
Generate random 3-digit numbers with advanced options
4 Digit Random Number Generator
Generate random 4-digit numbers instantly
5 Digit Random Number Generator
Generate random 5-digit numbers with filters
6 Digit Random Number Generator
Generate random 6-digit numbers for PINs and codes
7 Digit Random Number Generator
Generate random 7-digit numbers for local phone mockups and raffles
8 Digit Random Number Generator
Generate random 8-digit numbers for 2FA backup codes and date stamps
ASCII to HEX Converter
Translate ASCII strings to hexadecimal or decode hex payloads back to readable text
IP Lookup Tool
Reveal IP geolocation, ISP, ASN, timezone, and security flags with one click
JSON to CSV Converter
Convert JSON data to CSV format
Markdown to HTML Converter
Convert Markdown to HTML instantly
CSV to HTML Table Generator
Convert CSV data to HTML tables
JSON Formatter
Format and validate JSON data
JWT Token Decoder
Decode and inspect JWT tokens
Hash Generator
Generate MD5, SHA-1, SHA-256 hashes
API Endpoint Tester
Test REST API endpoints
CSS Minifier
Minify CSS code for production
HTML Entity Encoder/Decoder
Encode and decode HTML entities
HTTP Status Code Explainer
Understand HTTP status codes
Random JSON Generator
Generate random JSON data for testing
WordPress Hash Generator
Create and verify WordPress-compatible phpass password hashes in the browser
DNS Lookup Tool
Query A, AAAA, MX, NS, TXT, and CNAME records with resolver diagnostics
MX Lookup Tool
Check MX records and mail routing priorities for any domain
NS Lookup Tool
Validate authoritative nameserver delegation records for domains
Reverse IP Lookup Tool
Resolve PTR records to map IPv4 and IPv6 addresses back to hostnames
MAC Address Lookup Tool
Lookup device vendors from MAC OUI prefixes with searchable directory support
HTML Minifier
Minify HTML code with whitespace, comment, and attribute cleanup controls
HTTP Header Checker
Inspect response headers, redirects, and security header coverage for any URL
Browser Window Size Checker
Measure live viewport size, DPR, and active responsive breakpoint
Screen Resolution Tester
Preview websites at common device resolutions and custom viewport sizes
JSON Path Tester
Evaluate JSONPath expressions against JSON documents with result previews
IEEE-754 Analysis Tool
Break float32 and float64 values into sign, exponent, and mantissa bits
URI Template Parser
Expand URI templates into real URLs with editable path and query variables
Redirect Generator
Generate redirect snippets for Apache, Nginx, Netlify, Vercel, JS, and HTML
HTML Viewer
Render and preview raw HTML code inside a safe iframe
Domain IP Lookup
Resolve IPv4 and IPv6 addresses for any hostname or website domain
Meta Tag Generator
Generate SEO meta tags
Keyword Density Checker
Analyze keyword density in content
Long Tail Keyword Generator
Generate long-tail keyword ideas
Question Keyword Generator
Generate question-based keywords
Local Keyword Modifier
Add local modifiers to keywords
Autocomplete Keyword Suggester
Get autocomplete keyword suggestions
Credit Card Validator & Luhn Checker
Validate credit card numbers using the Luhn algorithm for payment sandbox testing
Password Strength Checker
Check password strength and security
XML Validator
Validate, prettify, highlight, and minify XML feeds, SOAP envelopes, and sitemaps
Color Contrast Checker
Check color contrast for accessibility
Robots.txt Generator
Generate custom robots.txt files with crawl rules and sitemaps
Open Graph Meta Tag Generator
Generate Facebook Open Graph & Twitter Card meta tags with live card preview
.htaccess Redirect Generator
Generate 301, 302, HTTPS, and WWW rewrite rules for Apache web servers
CSV to JSON Converter
Convert CSV spreadsheets into clean, formatted JSON arrays or objects
JavaScript Minifier
Minify JavaScript code to reduce file size and increase load speed
Schema.org JSON-LD Generator
Generate Google-rich snippet Schema.org JSON-LD structured data code
SQL Formatter & Prettifier
Format, beautify, and clean up unformatted SQL queries for MySQL, Postgres, and SQLite
Markdown Table Generator & CSV Converter
Create, format, and convert Markdown tables visually for GitHub READMEs and docs
Cron Expression Generator & Explainer
Build, test, and translate crontab cron expressions with instant plain-English explanations
User Agent Parser & Detector
Parse HTTP User-Agent strings to detect browser, version, OS, engine, and device type
cURL to JavaScript Fetch & Axios Converter
Convert cURL commands into JavaScript fetch(), Axios, Python requests, and PHP code
HTML to Markdown Converter
Convert raw HTML markup and web articles into clean Markdown text
CSS Glassmorphism UI Generator
Design modern frosted glass UI elements with backdrop-filter blur and transparency controls
CSS Clamp() Calculator & Fluid Typography Generator
Calculate CSS clamp() formulas for responsive fluid typography and spacing
JSON to TypeScript Interface Generator
Convert raw JSON objects into strongly-typed TypeScript interfaces and type aliases
Subnet Calculator (IPv4 CIDR & Netmask)
Calculate IPv4 subnets, CIDR blocks, usable host ranges, broadcast addresses, and binary netmasks
Google SERP Simulator & Snippet Previewer
Preview how your page appears on Google desktop and mobile search results with pixel width checks
Security Headers Generator & CSP Builder
Generate hardened HTTP security headers (CSP, HSTS, X-Frame-Options) for Nginx, Apache, and Next.js
CSS Gradient Generator & Color Palette Maker
Create linear, radial, and conic CSS gradients with multi-stop color controls and Tailwind export
Aspect Ratio Calculator & Dimension Resizer
Calculate proportional aspect ratios, CSS padding-top hacks, and display dimensions
Regex Tester & Regular Expression Matcher
Test, validate, and debug regular expressions in real-time with capture groups and flags
Cron Expression Explainer & Schedule Humanizer
Translate crontab schedules into plain English sentences and view upcoming execution times
UTM Parameter Parser & URL Builder
Inspect, parse, edit, and rebuild Google Analytics UTM tracking links and query parameters
Cryptographic Hash Identifier & Analyzer
Identify MD5, SHA-1, SHA-256, bcrypt, Argon2, and checksum algorithms with security ratings
SVG to PNG Converter Online
Convert vector SVG code or files into high-resolution PNG or JPEG images with transparency
Linux Chmod Permissions Calculator
Generate octal and symbolic Linux file permissions with copyable bash terminal commands
CSV to SQL Converter & Table Generator
Convert CSV data into SQL CREATE TABLE schemas and multi-row batch INSERT INTO statements
Code to Image Converter
Convert code snippets into beautiful social media screenshots with themes, gradients, and window frames
CSS Clip-Path Generator & Polygon Maker
Create custom geometric shapes, diagonal sections, and polygon masks with draggable visual control points
CSS Neumorphism & Soft UI Generator
Design tactile Soft UI cards, buttons, and elements with dual directional highlights and box-shadows
CSS Border-Radius & Fancy Blob Generator
Generate fluid organic shapes and keyframe morphing animations with the 8-value border-radius syntax
CSS Animation & Keyframe Generator
Build hardware-accelerated CSS keyframe animations with easing curves, duration controls, and live element preview
HTML to JSX Converter
Transform standard HTML5 and SVG code into clean React JSX with className mapping and style objects
Image Color Extractor & Palette Generator
Extract dominant color palettes and inspect individual pixel hex codes from any image with an eyedropper
Dummy JSON Generator
Generate realistic mock JSON datasets for frontend UI prototypes, database seeding, and REST API testing
SVG Path Visualizer & Inspector
Inspect and visualize SVG path commands (M, L, C, Z) on an interactive coordinate grid with length calculation
SVG Optimizer & Minifier
Clean and minify bloated SVG vector code from Illustrator and Figma for high-speed web production
Social Share & Open Graph Previewer
Simulate social links on Twitter, Facebook, LinkedIn, Discord, and Google SERPs with copyable meta tags
Favicon & Apple Touch Icon Generator
Create browser tab favicons and mobile app icons from emojis or initials with multi-size PNG bundle downloads
Audio Tone Generator & Frequency Synthesizer
Generate pure sound frequencies from 20 Hz to 20,000 Hz with real-time oscilloscope waveform visualizer
.env to Docker Compose Converter
Transform .env files into Docker Compose configurations and generate sanitized .env.example templates
Capital Gains Tax Calculator
Calculate short-term vs long-term capital gains tax on stocks, crypto, and real estate with NIIT thresholds
NGINX Config Generator
Generate production-ready NGINX server blocks for reverse proxies, Single Page Apps, SSL/TLS, and WebSockets
Dockerfile Generator
Generate optimized, multi-stage Dockerfiles with security hardening, layer caching, and automatic .dockerignore creation
CIDR IP Range Calculator
Calculate IPv4 subnet ranges, network addresses, broadcast boundaries, usable hosts, and binary bitmasks
Password Entropy Calculator
Calculate Shannon entropy bits, character pool sizes, and realistic GPU brute force cracking times according to NIST standards
CSP Header Generator
Build hardened Content Security Policy headers for Nginx, Next.js, and Apache with instant security audit scoring
JSON to Zod Schema Converter
Convert JSON payloads into TypeScript Zod validation schemas, UUID checkers, email rules, and inferred types
CSS Mesh Gradient Generator
Create fluid, multi-point aurora mesh gradients with interactive node coordinates, live CSS export, and HD wallpaper downloads
CSR & OpenSSL Command Generator
Generate Certificate Signing Requests (CSR) and zero-trust OpenSSL CLI commands with Subject Alternative Names (SANs)
Cloud Storage Pricing Calculator
Compare monthly storage, egress bandwidth, and API request costs across AWS S3, Cloudflare R2, Azure Blob, GCP, and Wasabi
Kubernetes Resource Calculator
Calculate pod CPU, memory requests, limits, cluster overcommit ratios, and node capacity planning with YAML export
SQL to Prisma Schema Converter
Convert SQL CREATE TABLE DDL statements into Prisma schema models with primary keys, relations, and enums
.gitignore Generator
Generate production-ready .gitignore files for Node, Python, Next.js, Rust, Go, macOS, and IDEs with custom rule merging
DNS Record Generator
Generate BIND, Cloudflare, and RFC-compliant zone records for A, AAAA, CNAME, MX, TXT, SPF, and DKIM
Sitemap XML Generator
Generate schema-compliant XML sitemaps with custom priorities, change frequencies, and bulk URL importing
SSH Key Generator
Generate secure Ed25519 and RSA 4096 SSH key pairs in-browser with automated OpenSSH terminal commands
Base58 Encoder & Decoder
Encode and decode Bitcoin, Solana, and IPFS Base58 strings to text or hex with instant client-side validation
Base32 Encoder & Decoder
Encode and decode RFC 4648 Base32 strings and 2FA TOTP secret keys to plain text or hex with instant conversion
HAR File Viewer
Inspect HTTP Archive (.har) logs, analyze network waterfall timings, and debug HTTP errors with 100% client-side privacy
SVG to JSX Converter
Transform raw SVG code into production-ready React JSX and TypeScript TSX components with camelCase attributes
CSS Triangle Generator
Generate pure CSS border triangles, tooltip arrows, and dropdown carets with live preview and Tailwind CSS export
CSS Text Shadow Generator
Design multi-layer CSS text shadows, neon glow, and 3D typography effects with real-time visual preview
HTML Table Generator
Build responsive HTML tables, modern Tailwind CSS layouts, and GitHub Markdown tables with an interactive WYSIWYG editor
TSV to JSON Converter
Convert Tab-Separated Values (TSV) from Excel or datasets into structured JSON arrays and keyed objects
SemVer Version Calculator
Calculate Semantic Versioning release bumps, evaluate caret (^) and tilde (~) ranges, and audit dependency constraints
Hreflang Tag Generator
Generate valid HTML hreflang link tags and XML sitemap hreflang blocks for multi-language and international SEO websites.
Canonical Tag Generator
Create valid canonical URL link tags to prevent duplicate content penalties, consolidate PageRank, and specify preferred search index URLs.
CSS Flexbox Generator
Interactive visual flexbox playground to tweak flex direction, wrap, justify-content, align-items, and export clean CSS.
CSS Grid Generator
Visual 2D CSS grid layout builder to configure rows, columns, gaps, and fr units with instant copyable CSS and HTML.
CSS Cubic-Bezier Curve Generator
Interactive cubic-bezier timing curve visualizer with physics animation previews and CSS transition code export.
SVG Wave Generator
Create smooth, organic multi-layered SVG waves and gradient section dividers for websites with instant SVG and CSS export.
WCAG Color Contrast Checker
Test foreground and background color pairs against WCAG 2.1 AA and AAA standards with visual text simulations and contrast ratios.
SSL Certificate Decoder
Inspect X.509 PEM certificates, check expiration countdowns, SAN domains, and cryptographic SHA-256 fingerprints with zero server logs.
cURL to Python Converter
Transform cURL command lines into clean, production-ready Python requests, async HTTPX, or Node.js fetch code in seconds.
Crontab Schedule Debugger
Translate 5-field cron expressions into human-readable English, calculate next execution dates, and test crontab syntax effortlessly.
JSON to YAML Converter
Convert JSON to YAML and YAML to JSON in real time. Fast, secure, client-side formatting for Kubernetes, Docker, and CI/CD.
Title Capitalization Tool
Capitalize headlines and article titles following Chicago, AP, APA, and MLA editorial rules automatically.
ULID Generator and Decoder
Generate and decode 128-bit sortable Crockford Base32 ULIDs and extract millisecond timestamps.
Webhook Signature Generator & Verifier
Generate and verify HMAC SHA-256 webhook signatures for Stripe, GitHub, Shopify, and custom endpoints.
TCP/UDP Port Number Lookup
Search standard TCP/UDP port numbers (0-65535), default database ports, protocols, and security risks.
Dockerfile Linter & Optimizer
Lint Dockerfiles for root user security, layer cache optimization, and multi-stage image shrinking.
SQL Injection (SQLi) Payload Explainer
Analyze SQL injection attack vectors with parser syntax breakdowns and secure parameterized code fixes.
CORS Header Generator
Generate production-ready Cross-Origin Resource Sharing (CORS) headers for Express, Nginx, Next.js, and Cloudflare.
JWT Token Generator
Generate, inspect, and sign JSON Web Tokens (JWT) with custom claims and browser-side HMAC-SHA256.
SSL Pinning Hash Generator
Calculate Subject Public Key Info (SPKI) SHA-256 pins for Android network_security_config and iOS TrustKit.
DNS SPF Record Generator
Build RFC 7208 compliant SPF DNS TXT records with Google, Microsoft, and SendGrid 10-lookup validation.
Git Merge Conflict Resolver
Resolve Git merge conflict markers (<<<<<<< HEAD, =======, >>>>>>>) side-by-side in your browser.
Opportunity Zone Tax Calculator
Calculate Qualified Opportunity Zone (QOZ) capital gains tax deferral, tax-free basis step-ups, and 10-year net IRR returns.
Subnet Mask & Wildcard Calculator
Calculate IPv4 subnets, inverted wildcard masks, CIDR network IDs, usable host ranges, and Cisco IOS statements.
Kubernetes Ingress YAML Generator
Generate production-grade Kubernetes Ingress YAML manifests with cert-manager Let's Encrypt TLS and Nginx annotations.
Redis Memory Sizing Calculator
Calculate Redis RAM requirements by data structure (Strings, Hashes, Sets, ZSets) accounting for jemalloc and cloud nodes.
Argon2 Hash Generator & Tuning Tool
Generate and configure RFC 9106 Argon2id password hashes with memory, iteration, parallelism, and OWASP compliance auditing.
Terraform Provider Generator
Generate Terraform provider blocks, remote state S3/DynamoDB backends, VPC networks, and security groups in clean HCL.
Black-Scholes Option Pricing Calculator
Calculate theoretical European Call and Put option prices with full Delta, Gamma, Theta, Vega, and Rho Greeks.
SOC 2 Compliance & Audit Cost Estimator
Estimate Year 1 and ongoing SOC 2 Type 1 and Type 2 compliance costs, auditor fees, pentests, and tooling.
Independent Contractor Misclassification Risk Calculator
Assess 1099 contractor misclassification legal risk against DOL 6-factor standards and model back-tax penalties.
SaaS Quick Ratio Calculator
Calculate your SaaS Quick Ratio: (New MRR + Expansion MRR) / (Churned MRR + Contraction MRR) and benchmark growth.
AWS Lambda Serverless Cost Calculator
Calculate serverless execution costs in GB-seconds, compare x86 vs Graviton2 ARM pricing, and forecast cloud spend.
FinCEN BOI Exemption & Deadline Checker
Check if your LLC or Corporation is exempt from FinCEN BOI reporting under the Corporate Transparency Act.
Non-Compete Enforceability Checker
Check if your employee non-compete clause is legally enforceable under state laws, wage thresholds, and FTC rules.
UK Capital Gains Tax (CGT) Property & Shares Calculator
Calculate HMRC Capital Gains Tax on residential buy-to-let properties (18%/24%) and shares with the £3,000 allowance.
SaaS Magic Number & Sales Efficiency Calculator
Calculate your SaaS Magic Number and CAC Payback period to benchmark Go-To-Market sales efficiency.
Cloud Data Egress Cost Calculator
Compare data transfer out bandwidth fees across AWS, Azure, Google Cloud, and Cloudflare Zero Egress.
Why Use Stilest Developer Tools?
Every tool in our Developer Tools collection is built specifically for creators, developers, and everyday users who demand fast, reliable utilities without bloated software installs, account creation gates, or hidden paywalls. By performing operations client-side in modern WebAssembly and native JavaScript engines, your data remains securely on your device without transmitting sensitive text, tokens, or code to third-party cloud servers.
No Sign-up Required
Jump straight to solving your problem. All tools are immediately interactive on page load without email verification or registration.
Mobile & Desktop Optimized
Clean responsive layouts engineered for fast performance and high usability on tablets, smartphones, and high-resolution monitors.