Free online tools for developers, IT professionals and SMBs
Free online tools grouped by area: development (JSON, hash, UUID, regex, cron), security and audit (JWT, headers, supply chain), calculators and utilities, games. No registration, no usage limits.
Developer tools
24 tools
JSON formatter and validator
Format, validate, minify, sort keys and generate TypeScript interfaces from JSON. Fully.
Open toolEncoder / Decoder online
Base64, URL, HTML entities, Unicode, JWT decode, images to Data URI. Six tools in one.
Open toolUnix timestamp converter
Epoch <-> ISO 8601 with live multi-timezone and automatic DST. Batch CSV for timestamp lists.
Open toolHash calculator
MD5, SHA-1, SHA-256, SHA-384, SHA-512 from text or file.
Open toolUUID, ULID, NanoID generator
UUID v4/v7, ULID timestamp-ordered, NanoID, bulk up to 10K, CSV/JSON export. Native crypto-safe.
Open toolMulti-language slug generator
URL-friendly slugs from Italian, Spanish, French, German, English. Proper diacritic handling, batch CSV.
Open toolColor picker and converter
HEX, RGB, HSL, OKLCH, Lab. WCAG AA/AAA contrast checker, palette generator.
Open toolQR code generator
QR codes for URLs, Wi-Fi networks, vCard contacts and SEPA wire transfers in EPC069-12 format with IBAN validation. PNG and SVG export, static payload with no intermediate redirect.
Open toolLorem ipsum generator
Classic Latin, Italian filler, Cicero original, geek/dev fillers, emoji. Multi-style.
Open toolText and JSON diff online
Side-by-side text or JSON comparison with the Myers algorithm, unified patch export format.
Open toolText case converter
UPPERCASE, lowercase, camelCase, snake_case, kebab-case, PascalCase, Title Case with proper accent handling.
Open toolYAML / JSON / TOML converter
Bidirectional YAML, JSON, TOML conversion with strict validation.
Open toolCSV / TSV / JSON converter
CSV or TSV to JSON and back, RFC 4180 compliant parser. Auto-detect delimiter, headers, encoding.
Open toolSQL formatter
Multi-dialect SQL formatter: MySQL, PostgreSQL, SQLite, MS SQL T-SQL, BigQuery, Snowflake, Oracle PL/SQL. Configurable indent, keyword case and minify mode.
Open toolHTML / CSS / JSON / XML minifier
Minify and beautify for HTML, CSS, JSON and XML with inline compression stats. Preserves significant whitespace inside pre, textarea, script and style.
Open toolRegex tester
Regex tester with match highlight, groups, flags (gimsuy). Pattern library categorized (email, URL, IP, phone, dates).
Open toolCron expression parser
Parse 5-field POSIX cron + aliases (@yearly, @hourly) + weekly visualizer + next 20 runs. Natural language input.
Open toolGlob pattern tester
Test glob patterns (*, **, ?, [abc], {a,b}) against file lists. Sh syntax + minimatch + gitignore.
Open toolJWT decoder
Decode JWT tokens with header and payload split, claim explainer, expiry countdown and optional HS256 signature verification via WebCrypto.
Open toolMock data generator
Fake data generator (users, emails, addresses, companies) multi-locale (en/it/es/de/fr). Output JSON, CSV, SQL INSERT.
Open toolOG image preview
Preview OpenGraph meta tags for Facebook, X/Twitter, LinkedIn, Discord. Validation of meta tags.
Open toolMarkdown <-> HTML converter
Bidirectional Markdown -> HTML and HTML -> Markdown conversion. GitHub Flavored, table support, live preview.
Open toolJSON to TypeScript/Go/PHP
Generate TypeScript interface, Go struct and PHP class from JSON. Nested objects, optional/required inference. Multi-target.
Open toolHTTP status codes reference
Complete HTTP status code reference RFC 9110 (1xx-5xx) + curl example for each + when to use vs when not.
Open toolSecurity & audit
8 tools
HTTP Security Headers Analyzer
Audit HTTP response headers for CSP, HSTS, X-Frame-Options, Permissions-Policy. NIS2 art. 24 + OWASP mapping. Severity-coded findings.
Open toolJWT security audit
Security audit of JWT tokens: alg=none detection, weak HS256 secret brute force, missing claims, oversized lifetime. OWASP-style findings with normative references.
Open toolApache/Nginx config linter
Security lint for Apache.htaccess or Nginx server blocks. Auto-detects dialect. Findings on weak SSL, exposed status, missing headers.
Open toolComposer audit
Parse composer.json/lock with statistics, EOL detection (Laravel/Symfony/PHPUnit), recommendations. Triage tool, no remote CVE lookup.
Open toolSecure password generator
120 random passwords generated with the unbiased method, ASCII and alphanumeric, click to copy.
Open toolMojibake steganography
Light Unicode-safe steganography: each byte becomes a random higher codepoint.
Open toolDNS over HTTPS tester
Browser-side DoH queries via Cloudflare 1.1.1.1. Types A, AAAA, MX, TXT, NS, CNAME. No backend, fully.
Open toolEmail DNS validator (SPF, DKIM, DMARC)
Parser and validator for SPF, DKIM, DMARC records + MX lookup + multi-resolver compare (Cloudflare, Google, Quad9). For email deliverability audits.
Open toolCalculators & utilities
1 tools
Games
1 tools
Why these tools
Every tool in this hub solves a concrete problem encountered in real consulting work. Developer tools for everyday code work (formatters, encoders, hash, UUID, regex, cron). Security and audit tools for hardening web servers, JWT analysis, supply chain audits. Calculators and utilities for daily use. Games to take a five-minute break. All free, all maintained.
Need a custom-built tool for your company?
If one of these tools inspired you, but your use case requires integration into your backend, custom logic, or end-to-end automation, let's talk. I do senior backend consulting on PHP, Laravel, Symfony, unmanaged Linux infrastructure, applied cybersecurity, AI/LLM integration in production.
Get in touch