Free Developer Tools
Fast, private, open-source tools that run entirely in your browser. No uploads, no tracking, no accounts.
Favicon Generator
Generate favicons from text, emoji, or images. Download as ICO, PNG, SVG with all required sizes.
JSON Formatter
Format, validate, and minify JSON. Syntax highlighting, error detection, and tree view.
Meta Tag Generator
Generate SEO meta tags, Open Graph, and Twitter Cards. Live preview of Google and social media results.
Base64 Encoder & Decoder
Encode text to Base64 or decode Base64 back to text. Supports UTF-8 and URL-safe variants.
Color Converter
Convert colors between HEX, RGB, and HSL. Visual color picker with live preview and CSS output.
CSS Unit Converter
Convert between px, rem, em, %, vh, and vw. Customizable base font size and viewport dimensions.
Hash Generator
Generate MD5, SHA-1, SHA-256, and SHA-512 hashes from any text. Instant, private, and browser-based.
URL Encoder & Decoder
Encode special characters for URLs or decode percent-encoded strings. Supports encodeURIComponent and encodeURI modes.
Regex Tester
Test regular expressions with real-time match highlighting, capture groups, flags, and a quick reference cheat sheet.
Lorem Ipsum Generator
Generate customizable placeholder text — paragraphs, sentences, or words. Copy as plain text or HTML.
UUID Generator
Generate UUID v4 and v1 identifiers. Bulk generation, validation, and version detection. Copy instantly.
JWT Decoder
Decode JSON Web Tokens to inspect header, payload, and claims. Check expiration status and copy decoded data.
Timestamp Converter
Convert between Unix timestamps and human-readable dates. Supports seconds, milliseconds, timezones, and relative time.
Markdown Preview
Live Markdown editor with instant preview. Supports GFM syntax including tables, code blocks, and lists.
CSS Gradient Generator
Create beautiful CSS gradients visually. Linear and radial types, color stops, presets, and instant CSS output.
Diff Checker
Compare two texts side by side. See additions, deletions, and unchanged lines highlighted with diff statistics.
Password Generator
Generate strong, random passwords with customizable length, character types, and entropy-based strength meter.
QR Code Generator
Generate QR codes from any text or URL. Customize colors and size, download as PNG or SVG.
Cron Expression Builder
Build cron expressions visually with field editors. Human-readable descriptions, next execution preview, and presets.
JSON to CSV Converter
Convert JSON arrays to CSV or CSV back to JSON. Custom delimiters, nested object flattening, and instant download.
Text Case Converter
Convert text between camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE, and 6 more formats.
Placeholder Image Generator
Generate custom placeholder images with any dimensions, colors, and text overlay. Download PNG or copy data URL.
SQL Formatter
Format, beautify, and minify SQL queries. Syntax highlighting, configurable indentation, and keyword casing.
JSON to YAML Converter
Convert between JSON and YAML formats. Bidirectional, configurable indentation, inline arrays support.
Chmod Calculator
Calculate Unix file permissions visually. Interactive checkbox grid, octal and symbolic notation, common presets.
Box Shadow Generator
Create CSS box-shadow visually. Multiple shadow layers, color picker, inset toggle, and ready-to-copy CSS.
Border Radius Generator
Design CSS border-radius visually. Independent corner control, px and % units, shape presets, live preview.
Aspect Ratio Calculator
Calculate aspect ratios from dimensions. Lock ratio, common presets, resolution table, and CSS output.
Image Compressor
Compress images in your browser. Adjust quality, resize, and convert to JPEG, WebP, or PNG. No uploads.
SVG to PNG Converter
Convert SVG code or files to PNG images. Choose scale (1x–4x), background color, and download instantly.
HTML Entity Encoder
Encode and decode HTML entities. Named, decimal, and hex formats. Reference table for common characters.
Color Palette Generator
Generate color palettes from a base color. Complementary, analogous, triadic, and more harmony types with shades.
Text Shadow Generator
Create CSS text-shadow effects visually. Multiple layers, live preview, presets like neon, glow, retro, and fire.
CSV to SQL Converter
Convert CSV data to SQL INSERT statements. Supports PostgreSQL, MySQL, SQLite, and SQL Server dialects.
LLM Token Counter
Estimate token counts for GPT-4o, Claude, Llama, Gemini, and more. See context window usage instantly.
Character Counter
Count characters, words, sentences, paragraphs, and bytes. See reading time and letter frequency.
HTTP Status Codes
Complete reference of HTTP status codes with descriptions. Search, filter by category, and learn when to use each code.
CIDR Calculator
Calculate subnet masks, IP ranges, network and broadcast addresses from CIDR notation. Quick reference table included.
JWT Generator
Create and sign JSON Web Tokens with HS256/384/512. Add claims, set expiration. Signed client-side with Web Crypto API.
CSS Flexbox Playground
Build and visualize flexbox layouts interactively. Adjust direction, wrap, alignment, gap, and child properties with live preview.
CSS Grid Generator
Design CSS Grid layouts visually. Define columns, rows, gaps, and item placement with live preview.
CSS Animation Generator
Create CSS @keyframes animations visually. Define keyframes, timing, easing, and transforms with live preview.
Glassmorphism Generator
Create frosted glass UI effects with customizable blur, opacity, and borders. Live preview on a vibrant background.
Neumorphism Generator
Create soft UI (neumorphic) effects with light and dark shadows. Customize shape, distance, blur, and intensity.
Coming Soon
4 plannedCrontab Validator
Validate cron expressions and debug scheduling issues with detailed error messages.
Tailwind Color Picker
Browse and search Tailwind CSS color palette. Copy class names, HEX, and RGB values.
Regex Generator
Generate regular expressions from natural language descriptions. Pattern builder with examples.
Open Graph Preview
Preview how your URL will appear on Twitter, Facebook, LinkedIn, and Slack before sharing.
Why NexusTools?
100% Browser-Based
Your data never leaves your device. All processing happens locally in your browser.
No Account Required
Just open and use. No sign-ups, no email harvesting, no paywalls.
Fast & Free
Lightweight tools that load instantly. Free forever, supported by minimal ads.
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