Developer Utilities
Convert, inspect and validate code artifacts — JSON, JWT, cron, .env — without ever pasting a secret to a server.
56 tools · all 100% in-browser · zero uploads
JSON to CSV Converter
Convert JSON arrays to clean CSV or TSV with auto-flattening of nested objects. Zero-click, zero-upload, spreadsheet-ready output.
Cron Schedule Visualizer
Decode any cron expression into plain English and preview the next 5 execution timestamps in your local timezone.
.env File Validator
Catch duplicate keys, unbalanced quotes and syntax errors in .env files before they silently break a deployment.
JWT Decoder & Inspector
Decode JWT headers and payloads instantly, read iat/exp/nbf as human dates, and spot expired tokens — zero server.
Base64 Image Decoder
Decode Base64 strings into images, detect format, preview, and download — all inside your browser.
URL Query String Inspector
Parse any URL into base URL and query parameters, then edit and rebuild. Essential for API debugging.
HTML Entity Encoder / Decoder
Encode special characters to HTML entities and decode them back — live, offline, bidirectional.
Spreadsheet to Markdown Table
Copy cells from Excel or Google Sheets and convert them to a properly formatted GitHub Markdown table in one paste.
String Case Switcher
Convert any text between camelCase, PascalCase, snake_case, kebab-case and 6 more naming conventions simultaneously.
Regex Tester & Debugger
Test regular expressions against any text with live match highlighting, capture group inspection, and find-and-replace.
Markdown Previewer & Editor
Write Markdown with a live split-pane HTML preview — headings, code blocks, tables, blockquotes — offline, no account.
Lorem Ipsum Generator
Generate any amount of lorem ipsum placeholder text as paragraphs, sentences, words or bytes — plain text or HTML, instantly.
Password Strength Checker
Analyze password strength with entropy, estimated crack time, detailed criteria checklist and a built-in secure password generator.
JSON Formatter & Validator
Format, validate, minify, or sort JSON data instantly — with error highlighting, line counts, key counts and size comparison.
Number Base Converter
Convert numbers between binary, octal, decimal and hexadecimal instantly — with two's complement, ASCII lookup and a base-16 reference table.
Text Diff Checker
Compare two texts side-by-side and highlight added, removed and unchanged lines, words or characters with similarity percentage.
Unix Timestamp Converter
Convert Unix timestamps to human-readable dates and back — supports ISO 8601, relative time ("3 days ago") and common timezones.
Hash Generator (MD5 / SHA)
Generate MD5, SHA-1, SHA-256, SHA-384 and SHA-512 hashes from any text — all in-browser, nothing uploaded to a server.
cURL to Fetch & Python Converter
Convert terminal curl commands to clean JavaScript fetch() or Python requests code instantly with 1-click copy.
Conventional Commits Builder
Interactive generator for standardized Conventional Commits (feat, fix, breaking change) with 1-click git CLI command.
IPv4 CIDR Subnet Calculator
Calculate subnet masks, wildcard masks, usable IP ranges, and host counts for any IPv4 CIDR block with interactive slider.
JavaScript Keycode & Key Event Inspector
Inspect keyboard events in real time: key, code, keyCode, location, modifier keys, and copyable addEventListener snippet.
SVG to React JSX Component Converter
Convert raw SVG markup into clean, typed React/Next.js functional components with camelCase attributes and props spreading.
Google SERP Title & Description Truncation Test
Simulate Google desktop and mobile SERP snippets with exact Arial 20px pixel width measurement to prevent title truncation.
Discord Dynamic Timestamp Tag Generator
Generate dynamic Discord markdown timestamps (<t:unix:R>, <t:unix:F>) that automatically adjust to every user's local timezone.
Sitemap XML URL Extractor
Extract, deduplicate, and filter all page URLs from XML sitemaps with 1-click copy and downloadable CSV spreadsheet export.
Duplicate Line Remover & List Sorter
Remove duplicate lines from text lists, trim whitespace, and sort alphabetically or reverse with case-sensitivity controls.
Whitespace & Empty Line Cleaner
Clean redundant spaces, collapse multiple blank lines, trim trailing line whitespace, and convert tabs to spaces.
SQL Formatter, Beautifier & Minifier
Format, clean, indent, and uppercase messy SQL queries across PostgreSQL, MySQL, SQLite, and SQL Server in your browser.
Robots.txt Generator & AI Scraper Blocker
Build search-engine-compliant robots.txt files with 1-click protection against AI scrapers, custom disallows, and sitemap directives.
User-Agent String Parser & Device Inspector
Inspect and decode HTTP User-Agent strings to identify browser version, operating system, layout engine, and bot/crawler identity.
Markdown to Semantic HTML Converter
Convert Markdown into semantic HTML with live visual rendering preview, copyable HTML code, and document composition metrics.
Semantic Versioning (SemVer) Diff Comparator
Compare software release numbers, classify SemVer bumps (MAJOR, MINOR, PATCH), and verify npm caret (^) and tilde (~) compatibility.
SVG Preview & Metadata Optimizer
Clean XML prologs, editor namespaces, and bloat from Illustrator and Inkscape SVGs with live canvas preview.
JSON Minifier & Payload Compressor
Strip all indentation, line breaks, and whitespace from JSON to produce compact single-line production payloads.
YAML to JSON & JSON to YAML Converter
Bi-directional converter for YAML and JSON configuration files (Docker, Kubernetes, GitHub Actions) with zero server transmission.
JSON Schema to Markdown Generator
Convert JSON Schema contracts into clean GitHub Flavored Markdown parameter tables for API documentation.
SSL Certificate Signing Request (CSR) Decoder
Decode and inspect PEM-encoded PKCS#10 Certificate Signing Requests to verify Common Name, SANs, and key strength.
Free Vector SVG QR Code Generator
Generate permanent vector SVG QR codes with custom colors, rounded dots, and zero redirects or subscriptions.
HTML Meta Refresh Redirect Generator
Create lightweight single-file HTML meta refresh redirect pages with customizable delay, canonical tags, and noindex shields.
Multilingual Hreflang Tag & XML Sitemaps Builder
Generate bidirectional hreflang link tags and XML sitemap markup for international SEO with ISO 639-1 language codes and x-default fallback.
Text Table Column Extractor & Data Filter
Extract, isolate, and reformat specific columns from CSV, TSV, pipe-delimited, or space-separated tabular text into flat lists, SQL IN clauses, or JSON arrays.
Scientific Notation & Standard Form Converter
Convert decimal numbers into normalized scientific notation (m × 10ⁿ), engineering notation, and E-notation with precision significant figure controls.
Prime Number Checker & Sieve Generator
Check integer primality, extract prime factorizations, and generate lists of primes within custom ranges up to 100,000 using optimized trial division.
Greatest Common Divisor (GCD) & LCM Calculator
Compute the Greatest Common Divisor (GCD/HCF) and Least Common Multiple (LCM) for up to 10 numbers with Euclidean steps and prime factorizations.
Bidirectional Roman Numeral Converter
Translate Arabic numerals (1 to 3,999,999) to Roman numerals and decode Roman strings with support for classical subtractive and vinculum overline notation.
Quadratic Formula Solver & Parabola Analyzer
Solve ax² + bx + c = 0 for real and complex roots with step-by-step working, discriminant evaluation, vertex coordinates, and axis of symmetry.
Multi-Category Unit Converter Pro
Universal conversion across Length, Mass, Temperature, Speed, and Pressure with simultaneous multi-unit output tables and mathematical formulas.
Bulk Cryptographic UUID v4 Generator
Generate up to 1,000 cryptographically secure UUID v4 identifiers in bulk using native Web Crypto API with uppercase, lowercase, and hyphen toggles.
JSON to TypeScript Interface Generator
Infer clean, strongly typed TypeScript interfaces, type aliases, and nested object models from raw JSON payloads with optional field detection.
Interactive HTTP Status Code Reference & Diagnostic Guide
Search and inspect RFC specifications, diagnostic runbooks, and client/server error causes for all standard IETF HTTP response status codes.
Visual Unix Chmod Permissions Calculator
Calculate Unix file permissions using an interactive read/write/execute checkbox grid. Output octal (755), symbolic (-rwxr-xr-x), and terminal commands.
UTF-8 Base64 Text Encoder & Decoder
Encode plain text to standard RFC 4648 Base64 and decode Base64 strings back to clean UTF-8 with full international character and emoji support.
RFC 3986 URL Percent-Encoding Encoder & Decoder
Translate unsafe characters into RFC 3986 percent-encoded strings (%20, %2F) and decode complex URL parameters with diff inspection.
Cryptographic Password & Passphrase Generator
Generate high-entropy, breach-resistant passwords using the native Web Cryptography API with character set toggles and Shannon entropy ratings.
Text to International Morse Code Audio Player
Translate alphanumeric text into standardized ITU Morse code (• and —) and synthesize authentic 550Hz CW audio tones with adjustable WPM playback speeds.
Working in Developer Utilities
Every developer accumulates tiny friction points during a working day: a JSON payload that needs to become a spreadsheet row, a cron expression inherited from a legacy server, a JWT whose expiry you need to sanity-check before shipping a fix. ASG Tools' developer utilities attack exactly these moments. Each utility is a single-purpose micro tool that opens instantly, does one job well, and never sends your data anywhere — the parsing, conversion or validation happens inside your own browser tab using pure JavaScript and native Web APIs.
That zero-server architecture is not a marketing line; it changes what you can safely paste. Production JWTs, private .env files, customer data exports — all of them can flow through these tools without ever crossing the network, because there is no backend to receive them. Open DevTools and watch the Network tab: after the page loads, not a single request carries your input. For teams working under NDA, security auditors, or anyone handling regulated data, that property turns a handy utility into the only acceptable kind of utility.
The category grows with every rollout phase. Batch 1 ships the JSON to CSV converter, the cron schedule visualizer, the .env validator and the zero-server JWT inspector — the four tools our user research flagged as the most repeated daily friction points. Later batches will add query-string builders, hash generators, diff viewers and more, all under the same privacy contract.